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<rss version="2.0">
<channel>
<title>chudnick.com</title>
<description>chudnick.com</description>
<language>en-us</language>
<link>https://chudnick.com/rss.xml</link>
<item>
<title>LUKS Block Device Encryption</title>
<guid>https://www.chudnick.com/articles/luks.html</guid>
<link>https://www.chudnick.com/articles/luks.html</link>
<pubDate>Sat, 18 Jun 2022 15:46:21 -0400</pubDate>
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<body>
<header><h1>LUKS Block Device Encryption</h1></header>
<main>
<p>Linux Unified Key Setup (LUKS) is a method for encrypting
block devices that is built-in to the Linux Kernel. In this tutorial
I will be showing how to create an encrypted USB drive with LUKS, but
this process is applicable to other types of storage.
<strong>This process will wipe all data on the device that you
encrypt so make backups beforehand if needed</strong>.</p>
<h2>Install Packages</h2>
<p>Install cryptsetup and its dependencies</p>
<pre><code>apt install cryptsetup</code></pre>
<h2>Prepare the Drive</h2>
<p>If the device you are encrypting was previously used, you will
want to completely overwrite any data on it before encryption. This
can be done using <strong>dd</strong> as shown below. This could take
a very long time depending on the size and type of your drive.
Be sure that you enter the correct path to your drive as the
argument to <strong>of</strong>, and do not specify a partition:
<strong>/dev/sdb</strong> is correct, <strong>/dev/sdb1</strong> is
wrong. Obviously this will destroy any data on the device so be
absolutely sure you specify the correct device in the command
and have backups of data previously stored if needed.</p>
<pre><code>dd if=/dev/zero of=<em>/dev/sdX</em> status=progress</code></pre>
<h2>Encrypt the Drive</h2>
<p><strong>cryptsetup</strong> is the main command used to perform
LUKS-related tasks. This main command is followed by a subcommand
that specifies which action to perform. To create a LUKS partition
on a drive we need to use the subcommand <strong>luksFormat</strong>.
We also use the type option to explicitly say to use LUKS version 2
encryption. Run the command and then enter and confirm the
encryption password.</p>
<pre><code>cryptsetup --type luks2 luksFormat <em>/dev/sdX</em></code></pre>
<p>Now we need to open and map the encrypted LUKS device. This is done
by using the <strong>luksOpen</strong> subcommand. This subcommand takes
the device as the first argument and then a map target as the second. The
map target can be any string as long as a map does not already exist with
that name. In the example I will use <em>crypt</em>.
<pre><code>cryptsetup luksOpen <em>/dev/sdX crypt</em></code></pre>
<p>And then we just need to create a filesystem on the device; I will
be making an ext4 filesystem in the example. To
interact with an encrypted drive after it has been opened you need
to refer to its device mapper target, which is found under /dev/mapper.
Since we used <em>crypt</em> as the map target, our encrypted drive
is /dev/mapper/<em>crypt</em>. </p>
<pre><code>mkfs.ext4 /dev/mapper/<em>crypt</em></code></pre>
<p>After creating the filesystem created the encrypted drive
can now be mounted and used like any other device. Remember that
when mounting the device you refer to the device mapper target
(mount /dev/mapper/<em>crypt</em> /mnt/crypt).</p>
<p>In addition to unmounting the filesystem you should always close
the device mapping before removing your encrypted drive. This is
done with the <strong>luksClose</strong> subcommand and takes
the device mapping as the argument.</p>
<pre><code>cryptsetup luksClose /dev/mapper/<em>crypt</em></code></pre>
<h2>The LUKS Header</h2>
<p>The LUKS header sits at the front of your encrypted drive and is
responsible for managing access to the device. If the header is
damaged accessing your encrypted data will not be possible. Because of
this, you may want to make backups of the header, but before doing so
you need to weigh the risks and benefits.</p>
<p>The obvious benefit is that
in the event of damage to the LUKS header, you can easily restore a
backup and regain access to the data. However, having a backup of the
header makes it harder to wipe the LUKS device. Without a header
backup, overwriting the LUKS header on the device is enough to securely
wipe the drive. With backups, you need to either destroy all header
backups or overwrite all encrypted data on the device. The other main risk
is that an encryption password that is valid at the time you make a
backup will always be valid for that backup. For example, say you change
the encryption password on your device after making a backup because it
has been compromised. An attacker would be able to restore the header
backup and then use the compromised password to access the data.</p>
<p>The cryptsetup documentation refers to creating header backups
as making a trade-off between safety and security. You need to make a
decision based on your individual use-case. It's a good idea to
routinely update your header backups if you do choose to make them</p>
<p>When creating or restoring a header backup you always refer to the
block device in the command, not the device mapper taget. To create
a header backup:</p>
<pre><code>cryptsetup luksHeaderBackup <em>/dev/sdX</em> --header-backup-file <em>path/to/backup</em></code></pre>
<p>To restore a header from a backup:</p>
<pre><code>cryptsetup luksHeaderRestore <em>/dev/sdX</em> --header-backup-file <em>path/to/backup</em></code></pre>
<p>Note that is not necessary to store header backups on an encrypted
device. I would recommend storing backups on at least one non-encrypted
drive in case of an emergency.</p>
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<title>PAM OATH Two Factor Authentication</title>
<guid>https://www.chudnick.com/articles/pam-tfa.html</guid>
<link>https://www.chudnick.com/articles/pam-tfa.html</link>
<pubDate>Sat, 18 Jun 2022 15:45:01 -0400</pubDate>
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<header><h1>PAM OATH Two Factor Authentication</h1></header>
<main>
<p>In this article we are going to look at configuring two factor
authentication via PAM using OATH. This is a simple and private way
to increase the security of your systems. Even if you are not familiar
with the term, it is likely that you
have used OATH before. OATH (specifically TOTP) is the rotating 6
digit code that you get from scanning a QR code when setting up 2FA
on an account.</p>
<p>This example will show how to configure 2FA for SSH logins to a
server, but can easily be generalized to cover other programs or
even all authentication on a system. The two factors here will be
public key authentication and then the OATH/TOTP code.
<em>It is highly recommended that you remain SSHd into your server
until after testing to avoid locking yourself out in the event
of a configuration error.</em></p>
<h2>Install Packages</h2>
<p>You only need to install a single package on the server side.</p>
<pre><code>apt install libpam-oath</code></pre>
<p>On the client machine that will be SSHing to the server install
these two packages.</p>
<pre><code>apt install oathtool qrencode</code></pre>
<h2>Configure OATH</h2>
<p>Create the OATH configuration file <strong>/etc/users.oath</strong>.
This file will contain the OATH secret keys so permissions need to be
set to only allow the root user to view it.</p>
<pre><code>touch /etc/users.oath
chown root: /etc/users.oath
chmod 600 /etc/users.oath</code></pre>
<p>Generate a secret key for the TOTP. Treat this secret key as you
would your SSH or GPG private key. Anyone who has this key will be able
to generate the code needed to authenticate.</p>
<pre><code>openssl rand -hex 10</code></pre>
<p>Now we define the TOTP configuration for our user. If you were
setting this up for multiple users you would make one entry per line.
Open <strong>/etc/users.oath</strong> and add this line.
<em>user</em> is the username of the account you will SSH into.
Replace the long string of numbers and letters with the secret key
you just generated.</p>
<pre><code>HOTP/T30/6 <em>user</em> - <em>00112233445566aabbcc</em></code></pre>
<h2>Configure PAM</h2>
<p>Now we need to tell PAM to use OATH to authenticate sshd. Do that
by opening <strong>/etc/pam.d/sshd</strong> and adding the following
line to the top of the file.</p>
<pre><code>auth sufficient pam_oath.so usersfile=/etc/users.oath window=30 digits=6</code></pre>
<p>This tells PAM to consider a valid 6 digit code as fully authenticated
and to skip any other processing that may normally occur, such as
requesting a password.</p>
<h2>Configure SSHD</h2>
<p>We need to make a few changes to the sshd configuration to allow
OATH to work properly. Open the sshd configuration file at
<strong>/etc/ssh/sshd_config</strong> and make the following changes.</p>
<pre><code>AuthenticationMethods publickey,keyboard-interactive
PubkeyAuthentication yes
PasswordAuthentication no
ChallengeResponseAuthentication yes
UsePAM yes</code></pre>
<p>The <strong>AuthenticationMethods</strong> line specifically tells
sshd that a user needs to both have an authorized SSH key and know
the proper 6 digit code to login.</p>
<p>Restart sshd to apply the changes</p>
<pre><code>systemctl restart sshd</code></pre>
<h2>Test the Changes</h2>
<p>From your client ssh into your server as normal. Instead of
connecting as you have been, you should now see a prompt for your
one time password. You can use <strong>oathtool</strong> to get
the code. Again, replace the long string of numbers and letters
with the secret key you generated on the server.</p>
<pre><code>oathtool --totp -d6 <em>00112233445566aabbcc</em></code></pre>
<p>Enter that 6 digit code into the prompt and you will be logged
into your server.</p>
<p>Now, in the unlikely event that your SSH private key is stolen,
an attacker still won't be able to access your server!</p>
<h2>Managing your TOTP</h2>
<p>You probably don't want to run the oathtool command everytime you
need your code, and while you could make an alias, that would require
storing your secret key in plaintext. Here are some better options.</p>
<ul>
<li><strong>pass otp</strong> is an extension to the command-line
password manager <strong>pass</strong> for handling TOTP.
Use this if you are already using pass</li>
<li><strong>KeePassXC</strong> is a graphical password
manager that can manage TOTP</li>
<li><strong>Gnome Authenticator</strong> is a graphical
TOTP manager for the GNOME desktop environment</li>
</ul>
<p>You may also want to generate a QR code for easy setup on another
device. Rerun the same oathtool command as before with the -v flag
to get the base32 version of your secret key.</p>
<pre><code>oathtool --totp -v -d6 <em>00112233445566aabbcc</em>
--------------------------------
Hex secret: 00112233445566aabbcc
Base32 secret: <strong>AAISEM2EKVTKVO6M</strong>
Digits: 6
Window size: 0
TOTP mode: SHA1
Step size (seconds): 30
</code></pre>
<p>Then use qrencode to generate the QR code image.</p>
<pre><code>qrencode -o <em>totp.png</em> 'otpauth://totp/<em>user</em>@<em>server</em>?secret=<em>AAISEM2EKVTKVO6M</em>'</code></pre>
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<title>FreeIPA Server Setup</title>
<guid>https://www.chudnick.com/articles/freeipa-server.html</guid>
<link>https://www.chudnick.com/articles/freeipa-server.html</link>
<pubDate>Sat, 18 Jun 2022 15:44:21 -0400</pubDate>
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<header><h1>FreeIPA Server Setup</h1></header>
<main>
<p>FreeIPA is a centralized idenity management solution developed
by Redhat. It is in my opinion the most functional libre alternative
to Microsoft's Active Directory. Like AD, FreeIPA integrates all of
the pieces needed to setup a domain including LDAP, Kerberos,
a Certificate Authority, and much more.</p>
<p>I will be using Fedora 35 in this tutorial. As of Debian 11, the
FreeIPA server is still not in the Debian repos. You will need either
a Fedora or a RHEL machine. A CentOS fork may work also but I have not
tested that.</p>
<h2>FreeIPA in an Enterprise</h2>
<p>For readers exploring the use of FreeIPA in a business
environment, note that FreeIPA documentation explicitly states that
it is not a replacement for Active Directory. I have not personally
tried to join a Windows computer to a FreeIPA domain, and so I can't
speak to how well that would work. FreeIPA would also not be able to push
out policy to Windows machines as is done with Group Policy. FreeIPA
is though able to create inter-domain trusts with an existing AD
infrastructure.</p>
<h2>The Case for FreeIPA at Home</h2>
<p>Using a full Kerberos and LDAP identity management server may
seem like overkill at home. And if you only have a single computer
then it probably is. But scaling up even slightly, to perhaps a small
family each with their own computer, will make having FreeIPA
advantageous (<em>your family is all using Linux, right?</em>). This
will be especially apparent if you are hosting your own services.
If you are for instance hosting a Jellyfin media server that everyone
in your family accesses, you won't want them to juggle separate
passwords for Jellyfin when you could just have them use the same
password they do on the computer. This single/same sign-on capability is
one of the most practically useful aspects of FreeIPA.</p>
<h2>Install Packages</h2>
<p>We start as usual by installing the required packages.</p>
<pre><code>dnf install freeipa-server freeipa-dns</code></pre>
<h2>Set Hostname</h2>
<p>The server will need to have a fully qualified hostname
before setting up IPA. You will need both a hostname for the server
itself and the domain name you will want for the FreeIPA domain. I
will be using <em>ipaserver.myhome.local</em>, where
<em>ipaserver</em> is the hostname and <em>myhome.local</em> is the
domain name.</p>
<pre><code>hostnamectl set-hostname <em>ipaserver.home.local</em></code></pre>
<p>We'll also need to add a hosts file entry to
<strong>/etc/hosts</strong>. Open that file in an editor and add a new
line with the IP of the server, the fully qualified name, and the
hostname.</p>
<pre><code>192.168.1.10 ipaserver.myhome.local ipaserver</code></pre>
<p>Make sure to reboot the server before continuing to complete
the hostname change.</p>
<h2>Firewall Configuration</h2>
<p>We'll need to allow several ports for FreeIPA to function properly.
Fedora 35 uses firewalld by default but I am going to disable that
in favor of UFW here.</p>
<pre><code><em>#Install UFW</em>
dnf install ufw
<em># Stop and disable firewalld</em>
systemctl disable --now firewalld
<em># Configure UFW</em>
ufw enable
ufw allow ssh
ufw allow dns
ufw allow 88 comment kerberos
ufw allow 389 comment ldap
ufw allow 443 comment webui
ufw allow 636 comment ldaps
ufw default deny incoming
ufw reload</code></pre>
<h2>Configure FreeIPA</h2>
<p>Now we can run the FreeIPA setup script. This is an interactive but mostly
automatic process that will configure all of the IPA components. The
<strong>--mkhomedir</strong> flag will configure the server to create home
directories for IPA users on their first login and would otherwise have to be
done manually.</p>
<pre><code>ipa-server-install --mkhomedir</code></pre>
<p>That command will bring you into the install script. You will be prompted
several times before the bulk of the configuration happens. Default values
are show in brackets after the prompt. Let's run through those prompts.<br><br>
<strong>Do you want to configure integrated DNS (BIND)?</strong>:
<em>yes</em><br><br>
<strong>Sever host name</strong>: the default value should be showing
<em>ipaserver.myhome.local</em> which is what we want. Simply hit enter to acecpt
the default.<br><br>
<strong>Please confirm the domain name</strong>: The default here should be
correct <em>myhome.local</em> so hit enter to accept that.<br><br>
<strong>Please provide a realm name</strong>: This should just be the domain
name in all uppercase. If the default looks correct just hit enter.<br><br>
<strong>Directory Manager password</strong>: This is the password for an
administrator account used by system services. You will not need this for daily
use so I recommend setting it to a long randomly generated string. I have found
myself that using an extremely long password here will cause the installation to
fail. A password under 40 characters should be safe.<br><br>
<strong>IPA admin password</strong>: This is the password for your initial admin
user. Make this a strong password as this user has full admin rights for the
entire domain.<br><br>
<strong>Do you want to configure DNS forwarders</strong>: This allows you to
configure the IPA server to forward DNS requests to another DNS server for
zones it is not authoratitve for. The DNS server is configured by default as
a recursive DNS server so answering no does not prevent internet access. If you
have another DNS server that should be used instead then answer yes and provide
the IP address when prompted.<br><br>
<strong>Do you want to configure chrony with NTP server or pool address?</strong>
: Here you can configure a custom NTP server or pool for the NTP daemon chrony.
If you already have an NTP server on your network answer yes and provide its IP.
If you want to leave the deafult chrony configuration then answer no. Time
synchronization is very important in Kerberos so you should consider how you
want to achieve that on your network. If you do not have an NTP server you may
want to configure the IPA server as one later.<br><br>
<strong>Continue to configure the system with these values?</strong>: This is a
final confirmation before the script takes over and configures the IPA
components. Review the information printed and enter yes if it all looks correct.
</p>
<p>The install script will now run through configuration. This process usually
takes several minutes. When finished you should get a message saying
<strong>The ipa-server-install command was successful</strong>.</p>
<p>To finish, run this command to receive a Kerberos TGT. Provide the
password for the admin user when prompted.</p>
<pre><code>kinit admin</code></pre>
<h2>Accessing the Web Interface</h2>
<p>You are now able to manage FreeIPA through the web interface. You can
browse either to the IP or the hostname if your DNS is configured correctly.
You should see a screen similar to this.</p>
<img alt="FreeIPA Login Screen" src=../images/freeipa-webui.png>
<p>Login with the username admin and the password you set during the
insallation. You are now ready to begin configuring your IPA domain.</p>
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<title>Linux Software RAID</title>
<guid>https://www.chudnick.com/kb/mdadm-raid.html</guid>
<link>https://www.chudnick.com/kb/mdadm-raid.html</link>
<pubDate>Sun, 05 Jun 2022 15:19:11 -0400</pubDate>
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<header><h1>Linux Software RAID</h1></header>
<main>
<p><strong>mdadm</strong> is a tool that allows for creation and
management of software RAID arrays on Linux. Creating an array
is a rather straightforward process.</p>
<h2>Install packages</h2>
<p>The only package needed is mdadm itself</p>
<pre><code>apt install mdadm</code></pre>
<h2>Partition disks</h2>
<p>We'll need to parition the disks to be used in the array before
creating it. This isn't anything complicated, we will just be
creating a single partition using all the space on each disk.</p>
<p>Use <strong>lsblk</strong> to get a list of disks attached to your system.</p>
<img src=../images/raid/lsblk.png alt="lsblk command">
<p>Then use <strong>fdisk</strong> to edit the partition table of the
first disk. In my case this would be <strong>/dev/sdb</strong>.
Be sure that you are selecting the correct disk as selecting the
wrong one can result in data being lost.</p>
<pre><code>fdisk /dev/sdb</code></pre>
<p>Use <strong>g</strong> to create a new GUID partition table.
Use <strong>n</strong> to create a new partition, and then just press
enter at all of the prompts to accept the defaults. Finally use
<strong>w</strong> to write the changes. You can use lsblk again
to verify the change and you should see that /dev/sdb now has a
partition <strong>/dev/sdb1</strong>.</p>
<img src=../images/raid/fdisk.png alt="fdisk command">
<p>Repeat this process for your other disks before continuing.</p>
<h2>Create the array</h2>
<p>Creating the array is done with a single command, but takes just a
bit of planning.</p>
<ul>
<li>Define an ID for the array, which is just a
number identifier. I use <em>0</em> in the command.</li>
<li>Determine the RAID level you want to use. I am going to
use RAID5 in this example. The argument to --level is the
number of the RAID level</li>
<li>Determine the devices that will be used in the array.
Somewhat contrary to the argument name, these devices
will actually be the partitions of the disks and not the
disks themselves. In the command, give the number of
partitions (<em>3</em>) and then a space-separated list of the
partitions that will be active in the array
(<em>/dev/sdb1 /dev/sdc1 /dev/sdd1</em>).</li>
<li>If you want to have any spare devices in the array you
will define them with the --spare-devices argument. These are
defined in the exact same way as the active RAID devices. In
the example I use <em>1</em> spare <em>/dev/sde1</em>. Spare
devices are hot-spares that will automatically be inserted into
the array if one of the disks fails.</li>
</ul>
<pre><code>mdadm --create /dev/md<em>0</em> --level=<em>5</em> --raid-devices=<em>3</em> <em>/dev/sdb1 /dev/sdc1 /dev/sdd1</em> --spare-devices=<em>1</em> <em>/dev/sde1</em></code></pre>
<p>After creating the array run the following command to get details
and the status of the array. It will take a bit to initialize the
array, you will know this is done when the state is clean. You do not
need to wait for the array to completely intialize to continue.</p>
<pre><code>mdadm --detail /dev/md<em>0</em></code></pre>
<p>Take note of the UUID and name values as we will need them in the
next step.</p>
<p>Before moving on we need to make a filesystem on the array. I'm
going to make a simple EXT4 filesystem here.</p>
<pre><code>mkfs.ext4 /dev/md<em>0</em></code></pre>
<h2>Configuration Files</h2>
<p>Open the mdadm configuration file at
<strong>/etc/mdadm/mdadm.conf</strong> and append this line. Replace
<em>uuid</em> and <em>name</em> with the values you got when running
mdadm --detail, replace <em>0</em> whatever ID you chose.</p>
<pre><code>ARRAY /dev/md<em>0</em> metadata=1.2 UUID=<em>uuid</em> name=<em>name</em></code></pre>
<p>Optionally, create an <strong>/etc/fstab</strong> entry for
automounting of the array. Replace /mnt/raid with the directory
where you want to mount the array. If you made a filesystem other than
ext4 make sure to change that value.</p>
<pre><code>/dev/md<em>0</em> /mnt/raid ext4 defaults 0 1</code></pre>
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<title>Integrating InfluxDB and Icinga</title>
<guid>https://www.chudnick.com/kb/icinga-influx.html</guid>
<link>https://www.chudnick.com/kb/icinga-influx.html</link>
<pubDate>Tue, 31 May 2022 06:22:43 -0400</pubDate>
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<header><h1>Integrating InfluxDB and Icinga</h1></header>
<main>
<p>Icinga2 has built-in support for writing monitoring data to InfluxDB.
This makes Icinga quite extensible as it allows for other programs to read
the gathered data from InfluxDB. For example, Icinga does not have built-in
graphing support. But monitoring data can be written to InfluxDB and then
consumed by a dedicated graphing tool like Grafana.</p>
<h2>Install Packages</h2>
<p>Let's install a few necessary packages</p>
<pre><code>apt install influxdb influxdb-client ssl-cert</code></pre>
<h2>Generate self-signed certificate</h2>
<p>Now generate a self-signed certificate for accessing InfluxDB over TLS</p>
<pre><code>make-ssl-cert generate-default-snakeoil
usermod -aG ssl-cert influxdb</code></pre>
<h2>Create Database and Users</h2>
<p>Start and enable the InfluxDB service</p>
<pre><code>systemctl enable --now influxdb</code></pre>
<p>Now we'll create our database and users. We'll be creating 3 users with
different access rights. An admin user with full control over the database, a
user with write access that Icinga will use to write data to the database, and
a read-only user to allow external programs to read data from the database.</p>
<pre><code>influx -ssl -unsafeSsl -execute "create database icinga2; create user admin with password '<em>changeme</em>'; create user icingauser with password '<em>changeme</em>'; create user readonly with password '<em>changeme</em>'; grant all to admin; grant write on icinga2 to icingauser; grant read on icinga2 to readonly;"
</code></pre>
<h2>Configuration Files</h2>
<p>Then right InfluxDB's configuration file at
<em>/etc/influxdb/influxdb.conf</em></p>
<pre><code>reporting-enabled = false
[meta]
dir = "/var/lib/influxdb/meta"
[data]
dir = "/var/lib/influxdb/data"
wal-dir = "/var/lib/influxdb/wal"
[coordinator]
[retention]
[shard-precreation]
[monitor]
[http]
enabled = true
bind-address = ":8086"
auth-enabled = true
https-enabled = true
https-certificate = "/etc/ssl/certs/ssl-cert-snakeoil.pem"
https-private-key = "/etc/ssl/private/ssl-cert-snakeoil.key"
[ifql]
[logging]
[subscriber]
[[graphite]]
[[collectd]]
[[opentsdb]]
[[udp]]
[continuous_queries]
[tls]
min-version = "tls1.2"</code></pre>
<p>And restart InfluxDB to pickup the changes</p>
<pre><code>systemctl restart influxdb</code></pre>
<p>Then we need to configure Icinga to write data to our database. Start by
enabling the influxdb feature in Icinga</p>
<pre><code>icinga2 feature enable influxdb</code></pre>
<p>Now we tell Icinga how to write to our database. Open the configuration
file at <em>/etc/icinga2/features-available/influxdb.conf</em> and replace
with the following</p>
<pre><code>object InfluxdbWriter \"influxdb\" {
host = "127.0.0.1"
port = 8086
username = "icingauser"
password = "<em>icinga_password</em>"
ssl_enable = true
database = "icinga2"
flush_threshold = 1024
flush_interval = 10s
host_template = {
measurement = "$host.check_command$"
tags = {
hostname = "$host.name$"
}
}
service_template = {
measurement = "$service.check_command$"
tags = {
hostname = "$host.name$"
service = "$service.name$"
}
}
}</code></pre>
<p>And finally restart Icinga to make those changes live.</p>
<pre><code>systemctl restart icinga2</code></pre>
<p>Icinga2 will now be writing the data it collects to your InfluxDB instance.</p>
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<title>Postfix and Dovecot Mail Server</title>
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<pubDate>Mon, 30 May 2022 08:03:44 -0400</pubDate>
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<header><h1>Postfix and Dovecot Mail Server</h1></header>
<main>
<p>Postfix and dovecot will be the two primary pieces of our mail sever.
Postfix is the mail transport agent that handles the sending and
receiving of mail and dovecot is the IMAP server that will allow us to
access our mail from a mail client such as mutt. The server will also
have several other supporting components, a complete list of which is:</p>
<ul>
<li><em>SpamAssassin</em> for spam filtering</li>
<li><em>OpenDKIM</em> for DKIM verification and signing</li>
<li><em>Postgrey</em> for greylisting</li>
<li><em>Policyd-SPF</em> for SPF verification</li>
<li><em>OpenDMARC</em> for DMARC verification</li>
</ul>
<p>You can use <a href=https://git.chudnick.com/mail-tools/server/deploy-server>
this script</a> I have written to automate this process, but I would
recommend that you run through the tutorial first to understand
what is being done.</p>
<p>Please note that this tutorial is loosely intended for small personal mail
servers. Using PAM for authentication, as is done here, is not a scalable solution
for working with a large number of users. I do plan on covering Dovecot LDAP
authentication at some point which would be a better solution in an enterprise
setting.</p>
<h2>Install Packages</h2>
<p>Let's start by installing the required packages. Note that if you already
have Apache installed on the server, replace <em>python3-certbot-nginx</em>
with <em>python3-certbot-apache</em>.</p>
<pre><code>apt install postfix dovecot-imapd dovecot-sieve opendkim opendkim-tools spamassassin gnupg postgrey postfix-policyd-spf-python opendmarc dbconfig-no-thanks certbot python3-certbot-nginx</code></pre>
<p>During the installation of Postfix you will get a Debconf prompt in which
you need to select "Internet Site" and then provide your domain name,
<strong>example.com</strong>.</p>
<h2>Get a certificate</h2>
<p>Now we'll use Certbot to get a certificate for our server. If you are
using Apache replace <em>nginx</em> with <em>apache2</em>.</p>
<pre><code>systemctl stop nginx
certbot certonly --standalone -d <strong>mail.example.com</strong>
systemctl start nginx</code></pre>
<h2>Postfix Main Configuration</h2>
<p>In this section we will be doing the bulk of the postfix configuration.
The postconf command used throughout appends (or changes)
the specified configuration item in /etc/postfix/main.cf</p>
<h3>Network Configuration</h3>
<p>Let's start by configuring some network and domain information.</p>
<pre><code>postconf -e "myorigin = <strong>example.com</strong>"
postconf -e "mydestination = \$myhostname, \$mydomain, localhost"
postconf -e "mynetworks = 127.0.0.0/8 [::1]/128"
postconf -e "myhostname = <strong>mail.example.com</strong>"
</code></pre>
<p>Next, point postfix to the cerbot key and certificate, as well as the distro's
CA certificates.</p>
<pre><code>postconf -e "smtpd_tls_key_file=/etc/letsencrypt/live/<strong>mail.example.com</strong>/privkey.pem"
postconf -e "smtpd_tls_cert_file=/etc/letsencrypt/live/<strong>mail.example.com</strong>/fullchain.pem"
postconf -e "smtp_tls_CAfile = /etc/ssl/certs/ca-certificates.crt"
</code></pre>
<p>Harden the TLS configuration by forcing strong
protocols and ciphers, and requiring that authentication occur only over an
encrypted session.</p>
<pre><code><em># Require authentication over TLS and optionally use it for sending and receiving mail</em>
postconf -e "smtpd_tls_auth_only = yes"
postconf -e "smtpd_tls_security_level = may"
postconf -e "smtp_tls_security_level = may"
<em># Force the use of TLSv1.2 or TLSv1.3</em>
postconf -e 'smtpd_tls_mandatory_protocols = !SSLv2, !SSLv3, !TLSv1, !TLSv1.1'
postconf -e 'smtpd_tls_protocols = !SSLv2, !SSLv3, !TLSv1, !TLSv1.1'
postconf -e 'smtp_tls_mandatory_protocols = !SSLv2, !SSLv3, !TLSv1, !TLSv1.1'
postconf -e 'smtp_tls_protocols = !SSLv2, !SSLv3, !TLSv1, !TLSv1.1'
<em># Prefer server ciphers</em>
postconf -e "tls_preempt_cipherlist = yes"
<em># Force strong ciphers</em>
postconf -e "smtpd_tls_ciphers = high"
postconf -e "smtpd_tls_mandatory_ciphers = high"
postconf -e "smtp_tls_ciphers = high"
postconf -e "smtp_tls_mandatory_ciphers = high"
postconf -e "smtpd_tls_exclude_ciphers = aNULL, eNULL, EXP, LOW, MEDIUM, PSK, SRP, SHA1, kRSA, CAMELLIA, ARIA, DSS, RSA+AES, ADH, AECDH"
postconf -e "smtp_tls_exclude_ciphers = aNULL, eNULL, EXP, LOW, MEDIUM, PSK, SRP, SHA1, kRSA, CAMELLIA, ARIA, DSS, RSA+AES, ADH, AECDH"
</code></pre>
<h3>Local Recipients and Aliases</h3>
<p>Here we configure the bulk of the postfix built-in security settings which are
structured as a series of access restrictions. Do not edit these settings without
first reading the Postfix documentation as an incorrect change could inadvertently
make your server an open relay.</p>
<pre><code>postconf -e "smtpd_helo_required = yes"
postconf -e "smtpd_sender_login_maps = proxy:hash:/etc/postfix/login_maps"
postconf -e "smtpd_helo_restrictions = reject_unknown_helo_hostname, reject_non_fqdn_helo_hostname"
postconf -e "smtpd_sender_restrictions = reject_sender_login_mismatch, reject_non_fqdn_sender, reject_unknown_sender_domain"
postconf -e "smtpd_recipient_restrictions = reject_non_fqdn_recipient, reject_unknown_recipient_domain, permit_sasl_authenticated, reject_unauth_destination, check_policy_service unix:private/postgrey, check_policy_service unix:private/policyd-spf, reject_rbl_client zen.spamhaus.org"
postconf -e "smtpd_relay_restrictions = permit_sasl_authenticated, reject_unauth_destination"
postconf -e "smtpd_data_restrictions = reject_unauth_pipelining"
<em># Disable VRFY command to prevent harvesting of user accounts on system</em>
postconf -e "disable_vrfy_command = yes"
<em># Change smptd banner (hide distribution)</em>
postconf -e "smtpd_banner = \$myhostname ESMTP \$mail_name"</code></pre>
<p>Now, configure the local mail recipients and some aliases. We'll create
an account called <strong>mailadmin</strong> to receive mail addressed to
several other accounts. This is to keep <em>administrative</em> mail separate, but
you can certainly alias these to your main account later if you would prefer to see
it there.</p>
<pre><code><em># Set a custom local_recipient_maps here in order to avoid accepting mail for all local accounts</em>
postconf -e "local_recipient_maps = proxy:hash:/etc/postfix/local_maps \$alias_maps"
<em># You will need to manually set a password later to login as mailadmin</em>
adduser --disabled-login --shell /usr/sbin/nologin --gecos "" mailadmin
echo "# postfix aliases
postmaster: mailadmin
root: mailadmin
dmarc: mailadmin
" > /etc/aliases
<em># Update address databases</em>
echo "mailadmin@<em>mail.example.com</em> mailadmin" > /etc/postfix/login_maps
echo "mailadmin mailadmin" > /etc/postfix/local_maps
newaliases
postmap /etc/postfix/login_maps
postmap /etc/postfix/local_maps
</code></pre>
<h3>Mail Delivery</h3>
<p>These commands configure our mail delivery preferences. Mail will be
delivered inside a user's home folder with a maildir-style mailbox using
dovecot.</p>
<pre><code><em># Maildir delivery to $HOME/Mail/Inbox/</em>
postconf -e "home_mailbox = Mail/Inbox/"
<em># Deliver mail with Dovecot</em>
postconf -e "mailbox_command = /usr/lib/dovecot/deliver"</code></pre>
<h3>Header and Body Checks</h3>
<p>Header and body checks allow for some simple content filtering within Postfix.
This is done by scanning a message line by line for a configured regex string,
nothing more. For example, the first header check listed will reject a message
with an attachment of <em>ransomware.exe</em> but will not block it if sent with
no extension. This is mostly a protection against uneducated users and poorly
written mail clients. Other checks block vulnerabilities and improve privacy.</p>
<p>Create a new file <strong>/etc/postfix/header_checks</strong>, then open it in a
text editor and add the following</p>
<pre><code><em># Block files with common executable extensions</em>
/name=[^>]*\.(exe|pif|com|dll|vbs|bat|sh|bash|so|zip|tar|gz|cpio)/ REJECT
<em># Block message/partial vulnerability</em>
/message\/partial/ REJECT
<em># Remove Received string that is created when spamassassin reinjects message into postfix</em>
<em># This is to prevent leaking the userid of the spamassassin user</em>
/^Received:.*userid.*/ IGNORE
<em># Remove User-Agent strings from headers</em>
/^User-Agent: .*/ IGNORE</code></pre>
<p>Create another new file <strong>/etc/postfix/body_checks</strong>, and add this</p>
<pre><code><em># Block messages with iframes</em>
/<iframe/ REJECT" > /etc/postfix/body_checks</code></pre>
<p>And then run these commands to point postfix to the check files.</p>
<pre><code>postconf -e "header_checks = regexp:/etc/postfix/header_checks"
postconf -e "body_checks = regexp:/etc/postfix/body_checks"</code></pre>
<h2>Postfix Master Configuration</h2>
<h3>SMTP client</h3>
<p>This simple command configures the SMTP client process that is responsible
for sending your mail to other mail servers.</p>
<pre><code>postconf -M "smtp/unix=smtp unix - - y - - smtp"</code></pre>
<h3>Postscreen and SMTP Recipient</h3>
<p>Postscreen is a kind of firewall that sits in front of the Postfix SMTPD
process and receives all incoming traffic. Postscreen will drop connections
from IPs on a DNS blacklst, or from clients that violate the SMTP protocol by
speaking out of turn or sending non-SMTP commands. This adds up to less spam
connections and therefore a much lighter workload for your server.</p>
<pre><code>postconf -M "smtp/inet=smtp inet n - y - 1 postscreen"
postconf -M "smtpd/pass=smtpd pass - - y - - smtpd"
postconf -P "smtpd/pass/content_filter=spamassassin"
postconf -M "tlsproxy/unix=tlsproxy unix - - y - 0 tlsproxy"
postconf -M "dnsblog/unix=dnsblog unix - - y - 0 dnsblog"
postconf -e "postscreen_dnsbl_sites = zen.spamhaus.org"
postconf -e "postscreen_dnsbl_action = enforce"
postconf -e "postscreen_greet_action = enforce"
</code></pre>
<h3>Submission over TLS (submissions)</h3>
<p>Submission over TLS (aka submissions) is the process you will use to submit
mail to your server from a mail client. These commands configure submissions to
use a fully-encrypted session, as opposed to STARTTLS, and to only allow access
to authenticated clients.</p>
<pre><code>postconf -M "submissions/inet=submissions inet n - y - - smtpd"
postconf -P "submissions/inet/smtpd_tls_wrappermode=yes"
postconf -P "submissions/inet/smtpd_tls_security_level=encrypt"
postconf -P "submissions/inet/smtpd_tls_auth_only=yes"
postconf -P "submissions/inet/smtpd_sasl_auth_enable=yes"
postconf -P "submissions/inet/smtpd_client_restrictions=permit_sasl_authenticated,reject"
postconf -P "submissions/inet/smtpd_helo_restrictions="
postconf -P "submissions/inet/smtpd_sender_restrictions=reject_sender_login_mismatch"
postconf -P "submissions/inet/smtpd_recipient_restrictions=reject_non_fqdn_recipient,reject_unknown_recipient_domain,permit_sasl_authenticated,reject"
postconf -P "submissions/inet/syslog_name=postfix/submissions"
postconf -P 'submissions/inet/smtpd_tls_protocols=!SSLv2,!SSLv3,!TLSv1,!TLSv1.1'
postconf -P 'submissions/inet/smtpd_tls_mandatory_protocols=!SSLv2,!SSLv3,!TLSv1,!TLSv1.1'</code></pre>
<h3>OPTIONAL - submission with mandatory STARTTLS</h3>
<p>Having configured submission over TLS on port 465 this step is optional.
STARTTLS is considered by some to be less secure than full-session TLS and
may be vulnerable to exploitation.</p>
<pre><code>postconf -M "submission/inet=submission inet n - y - - smtpd"
postconf -P "submission/inet/smtpd_tls_security_level=encrypt"
postconf -P 'submission/inet/smtpd_tls_protocols=!SSLv2,!SSLv3,!TLSv1,!TLSv1.1'
postconf -P 'submission/inet/smtpd_tls_mandatory_protocols=!SSLv2,!SSLv3,!TLSv1,!TLSv1.1'
postconf -P "submission/inet/smtpd_sasl_auth_enable=yes"
postconf -P "submission/inet/smtpd_tls_auth_only=yes"
postconf -P "submission/inet/syslog_name=postfix/submission"
postconf -P "submission/inet/smtpd_helo_restrictions="
postconf -P "submission/inet/smtpd_client_restrictions=permit_sasl_authenticated,reject"
postconf -P "submission/inet/smtpd_helo_restrictions="
postconf -P "submission/inet/smtpd_sender_restrictions=reject_sender_login_mismatch"
postconf -P "submission/inet/smtpd_recipient_restrictions=reject_non_fqdn_recipient,reject_unknown_recipient_domain,permit_sasl_authenticated,reject"
</code></pre>
<h3>SpamAssassin Configuration</h3>
<p>Finally, this command tells Postfix how to interact with SpamAssassin.</p>
<pre><code>postconf -M "spamassassin/unix=spamassassin unix - n n - - pipe user=debian-spamd argv=/usr/bin/spamc --socket=/var/run/spamd.sock -e /usr/sbin/sendmail -oi -f \${sender} \${recipient}" </code></pre>
<h2>Dovecot Configuration</h2>
<p>Dovecot configuration is usually split up into many different files under
<strong>/etc/dovecot/conf.d/</strong> but here will be doing all of the
configuration in the primary config file
<strong>/etc/dovecot/dovecot.conf</strong>. Open that file with your editor
of choice, clear all of its contents, and then replace it with the following.</p>
<pre><code><em># /etc/dovecot/conf.d/10-auth.conf</em>
disable_plaintext_auth = yes
auth_username_format = %n
auth_mechanisms = plain
userdb {
driver = passwd
}
passdb {
driver = pam
}
<em># /etc/dovecot/conf.d/10-mail.conf</em>
mail_location = maildir:~/Mail:INBOX=~/Mail/Inbox:LAYOUT=fs
namespace inbox {
type = private
prefix =
separator = /
inbox = yes
subscriptions = yes
list = yes
}
<em># /etc/dovecot/conf.d/10-master.conf</em>
service imap-login {
# Run login processes in high-security mode (see: LoginProcess.txt in dovecot docs)
service_count = 1
# Disable unencrypted IMAP by setting port for plain IMAP to 0
inet_listener imap {
port = 0
}
inet_listener imaps {
port = 993
ssl = yes
}
}
<em># Allow postfix to use dovecot SASL</em>
service auth {
unix_listener /var/spool/postfix/private/auth {
mode = 0660
user = postfix
group = postfix
}
}
<em># /etc/dovecot/conf.d/10-ssl.conf</em>
ssl = required
ssl_key = </etc/letsencrypt/live/<strong>mail.example.com</strong>/privkey.pem
ssl_cert = </etc/letsencrypt/live/<strong>mail.example.com</strong>/fullchain.pem
ssl_client_ca_dir = /etc/ssl/certs
ssl_dh = </usr/share/dovecot/dh.pem
<em># Mozilla intermediate compatibility</em>
ssl_min_protocol = TLSv1.2
ssl_cipher_list = ECDHE+ECDSA+AESGCM:ECDHE+aRSA+AESGCM:ECDHE+ECDSA+CHACHA20:ECDHE+aRSA+CHACHA20:DHE+aRSA+AESGCM:!aNULL:!eNULL
ssl_prefer_server_ciphers = yes
ssl_client_require_valid_cert = yes
<em># /etc/dovecot/conf.d/15-lda.conf</em>
protocol lda {
mail_plugins = \$mail_plugins sieve
}
<em># /etc/dovecot/conf.d/15-mailboxes.conf</em>
namespace inbox {
mailbox Sent {
special_use = \Sent
auto = subscribe
}
mailbox Trash {
special_use = \Trash
auto = create
autoexpunge = 30d
}
mailbox Drafts {
special_use = \Drafts
auto = subscribe
}
mailbox Spam {
special_use = \Junk
auto = create
autoexpunge = 30d
}
mailbox Archive {
special_use = \Archive
auto = create
}
}
<em># /etc/dovecot/conf.d/20-imap.conf</em>
imap_capability = +SPECIAL-USE
<em># /etc/dovecot/conf.d/90-sieve.conf</em>
plugin {
sieve = ~/.dovecot.sieve
sieve_default = /var/lib/dovecot/sieve/default.sieve
sieve_global = /var/lib/dovecot/sieve/
}</code></pre>
<p>Then create the default sieve filtering script at
<strong>/var/lib/dovecot/sieve/default.sieve</strong></p>
<pre><code>require ["fileinto", "mailbox"];
/*
* Discard mail that has a spam score greater than or equal to 10
*/
if header :contains "X-Spam-Level" "**********" {
discard;
stop;
}
/*
* Discard messages marked as infected by a virus scanner
*/
if header :contains "X-Virus-Scan" "infected" {
discard;
stop;
}
/*
* If message is marked as spam (and falls below discard threshold) put into spam mailbox
*/
if header :contains "X-Spam-Flag" "YES" {
fileinto "Spam";
}</code></pre>
<p>And compile the script</p>
<pre><code>sievec /var/lib/dovecot/sieve/default.sieve</code></pre>
<p>Finally, configure PAM authentication for dovecot at
<strong>/etc/pam.d/dovecot</strong>. Append these changes leaving any include
statements intact.</p>
<pre><code>auth required pam_unix.so
account required pam_unix.so</code></pre>
<h2>OpenDKIM</h2>
<p>DKIM is a mail-verification method that cryptographically signs mail
to allow receivers to verify the authenticity of the sender. Our mail server
will use DKIM to validate signatures on incoming mail and sign outgoing mail. DKIM
requires a public key to be published via DNS, which will be done near the end of
the guide.</p>
<p>Start by generating the DKIM key</p>
<pre><code>opendkim-genkey -D /etc/dkimkeys -d <em>example.com</em> -s mail
chown opendkim: /etc/dkimkeys/*
chmod 600 /etc/dkimkeys/*
mv /etc/dkimkeys/mail.private /etc/dkimkeys/mail.pem</code></pre>
<p>Here we make a directory for the opendkim socket inside the postfix chroot and
make it accessible to the postfix user.</p>
<pre><code>mkdir /var/spool/postfix/opendkim
chmod 770 /var/spool/postfix/opendkim
chown opendkim:opendkim /var/spool/postfix/opendkim
usermod -aG opendkim postfix</code></pre>
<p>Edit the configuration file at <strong>/etc/opendkim.conf</strong>
to be as follows:</p>
<pre><code>On-BadSignature reject
On-Security reject
Syslog yes
SyslogSuccess yes
LogResults yes
Canonicalization simple
Mode sv
OversignHeaders From
Domain <strong>example.com</strong>
Selector mail
KeyFile /etc/dkimkeys/mail.pem
UserID opendkim
UMask 007
Socket local:/var/spool/postfix/opendkim/opendkim.sock
PidFile /run/opendkim/opendkim.pid
TemporaryDirectory /run/opendkim
InternalHosts 127.0.0.1
TrustAnchorFile /usr/share/dns/root.key
RequireSafeKeys True
AlwaysAddARHeader True
</code></pre>
<h2>OpenDMARC</h2>
<p>DMARC is another mail-verification technology that provides verification of the
address seen by end-users and either or both of SPF and DKIM.
<p>Like with OpenDKIM, we need to make a directory inside the postfix chroot
for the socket and assign proper permissions.</p>
<pre><code>mkdir /var/spool/postfix/opendmarc
chmod 770 /var/spool/postfix/opendmarc
chown opendmarc:opendmarc /var/spool/postfix/opendmarc
usermod -aG opendmarc postfix
</code></pre>
<p>Now we write the configuration file at <strong>/etc/opendmarc.conf</strong></p>
<pre><code>PidFile /run/opendmarc/opendmarc.pid
PublicSuffixList /usr/share/publicsuffix/public_suffix_list.dat
RejectFailures True
Socket local:/var/spool/postfix/opendmarc/opendmarc.sock
Syslog True
SyslogFacility mail
UMask 002
UserID opendmarc
HistoryFile /var/run/opendmarc/opendmarc.hist
SPFIgnoreResults True
SPFSelfValidate True
</code></pre>
<p>Then create the history file and set permissions.</p>
<pre><code>touch /var/run/opendmarc/opendmarc.hist
chown opendmarc:opendmarc /var/run/opendmarc/opendmarc.hist
chmod 664 /var/run/opendmarc/opendmarc.hist
</code></pre>
<p>Now that both OpenDKIM and OpenDMARC are configured we can define them as milters
in postfix. This will tell postfix to route mail through one or both of these milters
depending on whether it is incoming or outgoing.</p>
<pre><code>postconf -P "smtpd/pass/smtpd_milters=unix:opendkim/opendkim.sock,unix:opendmarc/opendmarc.sock"
postconf -P "submissions/inet/smtpd_milters=unix:opendkim/opendkim.sock"
<em># If you enabled submission on port 587 run this too</em>
postconf -P "submission/inet/smtpd_milters=unix:opendkim/opendkim.sock"
</code></pre>
<h2>Postgrey</h2>
<p>Postgrey implements a spam-filter technique known as greylisting, which
always rejects mail on the first try and for a period of time afterwards known
as the greylist period. The idea behind this being that legitimate senders will
send the mail again later, while spammers, in a rush to send as many messages as
possible before being blacklisted, will not.</p>
<p>Postgrey ships with an extensive whitelist domains that are known
to cause issues (mainly large providers that constantly send from different
addresses). This whitelist file is located at
<strong>/etc/postgrey/whitelist_clients</strong> and can be appended to include
any domain you do not wish to be subject to greylisting.</p>
<p>The configuration needed here is minimal, just open
<strong>/etc/default/postgrey</strong> and make these changes</p>
<pre><code>POSTGREY_OPTS="--unix=/var/spool/postfix/private/postgrey --privacy"
POSTGREY_TEXT="Greylisted - see https://www.greylisting.org"</code></pre>
<p>And then enable the service</p>
<pre><code>systemctl enable --now postgrey</code></pre>
<h2>Policyd-SPF</h2>
<p>SPF is yet another mail-verification technology that uses DNS records to
delegate specific servers as being authorized to send mail for the domain
(and implicitly all other servers as unauthorized). Policyd-SPF will perform
SPF checking of received mail and reject mail that fails SPF verfication.</p>
<p>First, tell postfix how to access Policyd-SPF</p>
<pre><code>postconf -e "policyd-spf_time_limit = 3600"
postconf -M "policyd-spf/unix=policyd-spf unix - n n - 0 spawn user=policyd-spf argv=/usr/bin/policyd-spf"</code></pre>
<p>And then edit the configuration file at
<strong>/etc/postfix-policyd-spf-python/policyd-spf.conf</strong></p>
<pre><code>debugLevel = 1
TestOnly = 1
HELO_reject = Fail
Mail_From_reject = Fail
Header_Type = AR
<em># These settings increase false-positive risk</em>
<em># Comment them if you want to reduce that risk</em>
PermError_reject = True
TempError_Defer = True</code></pre>
<h2>SpamAssassin</h2>
<p>SpamAssassin is a spam-filter that will scan all received mail and assign
a spam score based on configured rules. SpamAssassin is much heavier and more
resource-intensive than any of the previous spam-filtering/verification programs
we have configured. The postfix spam-filtering philosophy emphasizes the use
of lightweight checks before passing to an external content filter such as
SpamAssassin. Ideally, non-legitimate mail will have already been caught by one
of the previous methods, and SpamAssassin will only have to operate on a much
smaller subset of the mail that is sent to our server.</p>
<p>We have actually already told postfix to use SpamAssassin as a content filter
so in this section we just need to edit the configuration file
<strong>/etc/spamassassin/local.cf</strong>.</p>
<pre><code><em># Clearly indicate message is spam to user</em>
rewrite_header Subject *****SPAM*****
rewrite_header From *****SPAM*****
<em># Set required score to be marked as spam, 5.0 is default.</em>
<em># Lower to make policy more strict or raise to be more lenient.</em>
required_score 5.0
<em># Attach original messages as text/plain instead of message/rfc822 to spam reports</em>
report_safe 2
<em>Do not implicitly trust mail based on IP address except localhost</em>
trusted_networks 127.0.0.1/32
</code></pre>
<p>And finally make a few changes to the defaults file at
<strong>/etc/default/spamassassin</strong></p>
<pre><code>OPTIONS="--listen /var/run/spamd.sock --max-children 5"
PIDFILE=/var/run/spamd.pid
CRON=1</code></pre>
<h2>Wrapping Up</h2>
<p>At this point we have done all of the necessary configuration of the mail
server programs. We have just a few more minor tasks before your mail server
is operational.</p>
<h3>Configure Firewall</h3>
<p>We need to open the proper ports in the firewall. This example uses UFW.</p>
<pre><code>ufw allow 25 comment "smtp"
ufw allow 465 comment "submission over TLS"
<em># Run this next command only if you enabled submission on port 587</em>
ufw allow 587 comment "mail submission"
ufw allow 993 comment "IMAP over TLS"
ufw reload</code></pre>
<h3>Restart services</h3>
<p>Now let's restart the services to pick up any configuration changes.</p>
<pre><code>systemctl restart postfix
systemctl restart dovecot
systemctl restart opendkim
systemctl restart opendmarc
systemctl enable --now spamassassin
systemctl restart spamassassin
systemctl restart postgrey</code></pre>
<h3>DNS Entries</h3>
<p>Finally, we needs to set some required DNS records to enable mail flow and
verification. Begin by logging into your registrar or DNS host and editing
your DNS records.</p>
<h3>A Record</h3>
<p>If you did not set a wildcard A record earlier, you will need to set one now
for <strong>mail</strong>.
Alternatively, if you are running the mail server on the same server as your
website, you may want to instead make a CNAME record pointing mail to www.</p>
<h3>MX Record</h3>
<p>MX records tell servers attempting to send you mail where to send it. Open the
MX records section on your registrar and add a new record. An MX
record consists of a priority and a destination. Set the priority to 10 and the
destination to <strong>mail</strong>, or whatever your subdomain for this mail
server is. The host value can be left blank or may need to be set to "@"
depending on your registrar.</p>
<h3>DKIM TXT Record</h3>
<p>Now we will set the three TXT records we need. Open the TXT records tab on
your registrar.</p>
<p>We'll set the DKIM record first. The command we ran to
generate our DKIM keys also generates a DNS record for us which will be helpful
here. Print that to the screen with:</p>
<pre><code>cat /etc/dkimkeys/mail.txt</code></pre>
<p>You should get a lengthy output that looks something like the following. The
bolded portion is the value.</p>
<pre><code>mail._domainkey IN TXT ( <strong>"v=DKIM1; h=sha256; k=rsa; "
"p=MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAz50PSYL0Ob+OlF/0B77rwlzLe7zF6JKnxQNtMqcOCZ0Dar2FPhSUSz1FR0YmNuoShjMogdgKeojIzgRUqwK5GZ5Lz456qiXWkfAtLPc6UQ/WPoyEBGbJpRBYPGWdN4VoNcHkk/I4csvXW6MOI55ghPOwDmootPkCzNPR6gmNAXMe0duS4Lb+bIjy9QMOxGYVUaQ/b+7xar+fWw"
"bA3DjQa3jTLCydzzJpjEMfVaKqNhQ4N+ve7O2Mb3LF5k5B977mtok/6POjVG5HY8g6Pba+GzMFItR6nJO5EE2fyfv6cNbRLsZiM+WQmqvDBst5ejaeapy86F5PdJFlX/TUgXjtuwIDAQAB"</strong> ) ; ----- DKIM key mail for example.com</code></pre>
<p>You can cleanup the spacing of the value as your registrar should automatically
handle any needed splitting of the record. The parts you need to paste into your
registrar's web interface should then look like this.</p>
<pre><code><em># Name/Host</em>
mail._domainkey
<em># TXT Value</em>
"v=DKIM1; h=sha256; k=rsa; p=MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAz50PSYL0Ob+OlF/0B77rwlzLe7zF6JKnxQNtMqcOCZ0Dar2FPhSUSz1FR0YmNuoShjMogdgKeojIzgRUqwK5GZ5Lz456qiXWkfAtLPc6UQ/WPoyEBGbJpRBYPGWdN4VoNcHkk/I4csvXW6MOI55ghPOwDmootPkCzNPR6gmNAXMe0duS4Lb+bIjy9QMOxGYVUaQ/b+7xar+fWwbA3DjQa3jTLCydzzJpjEMfVaKqNhQ4N+ve7O2Mb3LF5k5B977mtok/6POjVG5HY8g6Pba+GzMFItR6nJO5EE2fyfv6cNbRLsZiM+WQmqvDBst5ejaeapy86F5PdJFlX/TUgXjtuwIDAQAB"</code></pre>
<h3>DMARC TXT Record</h3>
<p>The DMARC record should be as follows:</p>
<pre><code><em># Name/Host</em>
_dmarc
<em># Value</em>
"v=DMARC1; p=reject; rua=mailto:dmarc@<strong>example.com</strong>; fo=1"
</code></pre>
<h3>SPF Record</h3>
<p>Your SPF record will look like this. Remember to replace
<strong>mail.example.com</strong> with your server name.</p>
<pre><code><em># Name/Host</em>
@
<em># Value</em>
"v=spf1 a:<strong>mail.example.com</strong> -all"
</code></pre>
<h3>PTR Record</h3>
<p>Many mail servers rely on PTR records for verification purposes so we need
to make sure our server's IP address resolves to the proper domain name. If
your mail server is residing on a VPS, you will need to add this record on your
VPS provider's interface, consult their documentation for details.</p>
<h2>Creating your own Mail User</h2>
<p>Your mail server is now up and running. Let's create an email for you to
receive mail.</p>
<pre><code>useradd --shell /usr/sbin/nologin --create-home --user-group <strong>user</strong>
echo "<strong>user@example.com user</strong>" >> /etc/postfix/login_maps
echo "<strong>user user</strong>" >> /etc/postfix/local_maps
postmap /etc/postfix/login_maps
postmap /etc/postfix/local_maps
postfix reload
</code></pre>
<p>I have a script available for adding and removing users that you can find
<a href=https://git.chudnick.com/mail-tools/server/mailadm>here</a>.
<h3>Connecting From a Mail Client</h3>
<p>When connecting your account to a mail client you need to use these settings.</p>
<ul>
<li>Username: <strong>user@example.com</strong> </li>
<li>Password: the password for <strong>user@example.com</strong> </li>
<li>Server name: <strong>mail.example.com</strong> </li>
<li>IMAP Port: 993</li>
<li>IMAP Connection: SSL/TLS</li>
<li>SMTP Port: 465</li>
<li>SMTP Connection Type: SSL/TLS</li>
</ul>
<p>
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<title>Icinga2 Agent Configuration</title>
<guid>https://www.chudnick.com/kb/icinga-agent.html</guid>
<link>https://www.chudnick.com/kb/icinga-agent.html</link>
<pubDate>Mon, 30 May 2022 08:03:44 -0400</pubDate>
<description><![CDATA[<!DOCTYPE html>
<html lang=en>
<head>
<title></title>
<meta charset="utf-8"/>
<link rel="shortcut icon" href="favicon.ico"/>
<link rel='stylesheet' href='../style.css'/>
<meta name="viewport" content="width=device-width, initial-scale=1">
</head>
<body>
<header><h1>Icinga Agent Node Installation and Configuration</h1></header>
<main>
<p>With the Icinga master node configured, the servers we want
to monitor can now be added as agent nodes. As the names suggest,
the Icinga master node pushes the desired configuration to agent
nodes, while agent nodes report the configured status checks back
to the master. Communication between the master and agent nodes is
encrypted via TLS, with the master node acting as a certificate
authority.</p>
<p>You can find my script to automate this process
<a href=https://git.chudnick.com/server-scripts/monitoring/icinga-agent>
here</a>.</p>
<h2>Install Pakcages</h2>
<p>Start by installing the required packages on the server to be
monitored.</p>
<pre><code>apt install icinga2 monitoring-plugins
monitoring-plugins-contrib</code></pre>
<h2>Initialize PKI with master</h2>
<p>Now we need to setup the PKI that will be used for the communication
with the master node. The first step is to generate a certificate
signing request. Replace <em>hostname</em> with the FQDN of the server.</p>
<pre><code>icinga2 pki new-cert --cn "<em>hostname</em>" --cert "/etc/icinga2/pki/<em>hostname</em>.crt" --csr "/etc/icinga2/pki/<em>hostname</em>.csr" --key "/etc/icinga2/pki/<em>hostname</em>.key"</code></pre>
<p>Next we save the master node's public key certificate. Replace
<em>master</em> with the FQDN of your master node.</p>
<pre><code>icinga2 pki save-cert --host "<em>master</em>" --port 5665 --key "/etc/icinga2/pki/<em>hostname</em>.key" --trustedcert "/etc/icinga2/pki/trusted-master.crt"</code></pre>
<p>Receive signed certificate from the master node.</p>
<pre><code>icinga2 pki request --host "<em>master</em>" --port 5665 --key "/etc/icinga2/pki/<em>hostname</em>.key" --cert "/etc/icinga2/pki/<em>hostname</em>.crt" --trustedcert "/etc/icinga2/pki/trusted-master.crt" --ca "/etc/icinga2/pki/ca.crt"</code></pre>
<h2>Deploy configuration files</h2>
<p>Write Icinga configuration.</p>
<pre><code><strong>/etc/icinga2/icinga2.conf</strong>
include "constants.conf"
const NodeName = "$nodename"
include "zones.conf"
include "features-enabled/*.conf"
include <itl>
include <plugins>
include <plugins-contrib>
include <manubulon>
include <windows-plugins>
include <nscp>"</code></pre>
<p>Write zones configuration.</p>
<pre><code><strong>/etc/icinga2/zones.conf</strong>
echo "object Endpoint "<em>hostname</em>" {}
object Zone "<em>hostname</em>" {
parent = "<em>master</em>"
endpoints = [ "<em>hostname</em>" ]
}
object Zone "<em>master</em>" {
endpoints = [ "<em>master</em>" ]
}
object Endpoint "<em>master</em>" {
host = "<em>master</em>"
}
object Zone "director-global" {
global = true
}</code></pre>
<p>Write API configuration file.</p>
<pre><code><strong>/etc/icinga2/features-available/api.conf</strong>
echo "object ApiListener \"api\" {
accept_commands = true
accept_config = true
}</code></pre>
<h2>Enable API</h2>
<p>Next, we need to enable the API on the agent.</p>
<pre><code>icinga2 feature enable api
mkdir -p /var/lib/icinga2/certs
cp /etc/icinga2/pki/<em>hostname</em>.crt /etc/icinga2/pki/<em>hostname</em>.key /etc/icinga2/pki/ca.crt /var/lib/icinga2/certs/
chown -R nagios: /var/lib/icinga2/certs/</code></pre>
<h2>Sign agent CSR on Master</h2>
<p>The only action needed on the master node is to sign the agent's
CSR. Logon to your master node and run the following:</p>
<pre><code>fpr="$(icinga2 ca list | tail -1 | cut -d '|' -f 1)"
icinga2 ca sign $fpr</code></pre>
<h2>Configure Firewall</h2>
<p>Before finishing we need to open the proper firewall port.
I will use UFW in the example here and allow traffic only only
from the master node for best security.</p>
<pre><code>ufw allow proto tcp from <em>master-ip</em> to any port 5665</code></pre>
<h2>Restart Icinga on Agent</h2>
<p>Finally, restart the icinga service on the agent node.</p>
<pre><code>systemctl restart icinga2</code></pre>
<p>The Icinga agent node will now pull down configuration from the master.
You will know that this worked if <em>/var/lib/icinga2/api/zones</em>
begins to populate with new files.</p>
<p>
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<title>Icinga2 Director</title>
<guid>https://www.chudnick.com/kb/icinga-director.html</guid>
<link>https://www.chudnick.com/kb/icinga-director.html</link>
<pubDate>Mon, 30 May 2022 08:03:44 -0400</pubDate>
<description><![CDATA[<!DOCTYPE html>
<html lang=en>
<head>
<title></title>
<meta charset="utf-8"/>
<link rel="shortcut icon" href="favicon.ico"/>
<link rel='stylesheet' href='../style.css'/>
<meta name="viewport" content="width=device-width, initial-scale=1">
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<body>
<header><h1>Icinga Director</h1></header>
<main>
<p>Icinga Director is the web-based configuration tool for Icinga2.
Director provides a simple interface for configuring the various parts
of your monitoring environment. Even if you would rather do all of
the configuration from a terminal, I still recommend using Director for
its self-service API which allows new nodes to register with no interaction
required on the node (i.e. via a script).</p>
<p>Start by logging into your Icinga instance. If you followed the
<a href=icinga2-master.html>master installation guide</a> you should have
a tab labeled <strong>Icinga Director</strong>. Click on that, and you should
see something similar to this:</p>
<img src=../images/director/director.png>
<h2>Hosts</h2>
<p>Let's start by looking at the hosts section. Clicking on the hosts
button from the Director menu will present you with several options.
Click on host templates, and then click add to define our first host
template. Host templates are the building blocks of Icinga, they allow
for your nodes to be structured however you see fit, and then to have
monitoring checks automatically applied to them based on that structure.</p>
<p>I like to structure my host templates by operating system. For example,
I have a template called <strong>Linux Server</strong>, which is designed
to encompass all of the Linux servers in my environment. I then get more
specific, creating templates based on distro. These templates are children
of the Linux Server template, so they inherit whatever is applied to the
parent, but then can have distro-specific checks applied to themselves.</p>
<p>Start by giving your template a name - I will use <strong>Linux Server
</strong> here. Groups can be left empty for now, but you may want to
add groups and apply them to templates later. The check command should
be set to hostalive. Expand <strong>Icinga Agent and zone settings</strong>
and set <em>Icinga2 Agent</em>, <em>Establish connection</em>,
and <em>Accepts config</em> to Yes. Click store to save the template.
Your template should look like this:</p>
<img src=../images/director/hosttemplate.png>
<h2>Service templates</h2>
<p>Let's turn to services now. Return to the Director menu and select
Services. The services menu is structured similar to hosts, and we will
start with the service templates section. The idea behind service templates
is very similar to host templates. Typically, a service template corresponds
to a single monitoring command.</p>
<p>As an example, we'll create a service template for a monitoring
command that checks the status of a web server. Give the template a
name, set the check command to http, and finally expand <strong>Icinga
Agent and zone settings</strong> and set <strong>Run on agent
</strong> to no. We set this to no because we want Icinga to query
the web server externally instead of from the web server itself.</p>
<img src=../images/director/service-template.png>
<h2>Service sets</h2>
<p>Service sets are simply groups of service templates. They can be
structured however you see fit. Service sets can then be applied to
hosts/host templates to have the checks be automatically applied.</p>
<p>Add a new service set and give it a name. Then click on the services
tab and add all of the services you want to group into that set.
Here is an example of a service set <strong>Linux Standard</strong>
that has service checks that should be applied to all Linux servers.</p>
<img src=../images/director/service-set.png>
<p>To bring service sets and host templates together, return to your host
templates, select Linux Server, select the services tab, and then select
add service set and choose your desired set from the dropdown menu.</p>
<img src=../images/director/host-services.png>
<h2>Render your config</h2>
<p>When you have made all of the changes you need you will need to
render the Director configuration. Return to the Director menu,
select Config Deployment, and then select Render config.</p>
<h2>Self Service API</h2>
<p>In this last section we will look at what I think is the best feature
of Director which is the self service API. To enroll a host template
in the self service API, select the host template, select the agent
tab, and select generate self service api key. That's it!
The string of letters and numbers is the API key associated with this
host template. Hosts can be enrolled with this API key and Icinga
will automatically assign the host to this template. With proper
structuring, you can have hosts be completely provisioned without
touching Director. In the next article, we will use this to enroll
a host in Icinga with a shell script.</p>
<p>
<hr>
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<item>
<title>Icinga2 Master Setup</title>
<guid>https://www.chudnick.com/kb/icinga-master.html</guid>
<link>https://www.chudnick.com/kb/icinga-master.html</link>
<pubDate>Mon, 30 May 2022 08:03:44 -0400</pubDate>
<description><![CDATA[<!DOCTYPE html>
<html lang=en>
<head>
<title></title>
<meta charset="utf-8"/>
<link rel="shortcut icon" href="favicon.ico"/>
<link rel='stylesheet' href='../style.css'/>
<meta name="viewport" content="width=device-width, initial-scale=1">
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<body>
<header><h1>Icinga2 Master Installation</h1></header>
<main>
<p>
This tutorial will cover the installation of the Icinga2
monitoring application master node. This includes the base
program, the web frontend, and the web-based configuration tool.
This guide was made for Debian but should be similar
on other distributions.
</p>
<p>
I have a script available to automate the steps described in this
tutorial available
<a href=https://git.chudnick.com/path/to/script>from my git repo</a>.
<h2>Install Packages</h2>
<p>Here we will install the required packages. Icinga can use either MySQL
or PostgreSQL, however this tutorial will use MySQL/MariaDB.</p>
<pre><code>apt install icinga2 icingaweb2 icinga2-ido-mysql icingaweb2-module-director monitoring-plugins monitoring-plugins-contrib default-mysql-server</code></pre>
<h2>Secure MySQL</h2>
<p>This step is optional but strongly recommended.
The mysql_secure_installation script will harden your MySQL instance.</p>
<pre><code>mysql_secure_installation</code></pre>
<p>I recommend the following responses:
<ul>
<li><em>Switch to unix_socket authentication?</em><strong> Y</strong></li>
<li><em>Change the root password?</em><strong> Y</strong></li>
<li><em>Remove anonymous users?</em><strong> Y</strong></li>
<li><em>Disallow root login remotely?</em><strong> Y</strong></li>
<li><em>Remove the test database and access to it?</em><strong> Y</strong></li>
<li><em>Reload privilege tables now?</em><strong> Y</strong></li>
</ul>
</p>
<h2>Create Monitoring Database</h2>
<p>The next several sections will cover creating databases for the various
parts of Icinga. We'll start with the monitoring database.
The following command creates a MySQL database named <em>icinga2</em>
and grants permissions to a user named <em>ido_admin</em>. These values
are arbitrary, but I use them throughout the tutorial so I recommend leaving them
as is. You should definitely change the password though, which in the command
is <em>change me</em>. You will need this password and the passwords for the
other databases later, so make sure you save them.</p>
<pre><code>mysql -u root -e "CREATE DATABASE icinga2; GRANT SELECT, INSERT, UPDATE, DELETE, DROP, CREATE VIEW, INDEX, EXECUTE ON icinga2.* TO <em>ido_admin</em>@'localhost' IDENTIFIED BY '<em>change me</em>'; FLUSH PRIVILEGES;</code></pre>
<p>We then need to import the ido schema into the database.</p>
<pre><code>mysql -u root icinga2 </usr/share/icinga2-ido-mysql/schema/mysql.sql</code></pre>
<p>After importing the schema, we then write the configuration file that tells
the monitoring module how to connect to the database.</p>
<pre><code><strong>/etc/icinga2/features-available/ido-mysql.conf</strong>
library "db_ido_mysql"
object IdoMysqlConnection "ido-mysql" {
user = "ido_admin",
password = "<em>ido_password</em>",
host = "localhost",
database = "icinga2"
}"</code></pre>
<p>And finally we enable the monitoring module in Icinga.</p>
<pre><code>icinga2 feature enable ido-mysql</code></pre>
<h2>Create Icingaweb2 Database</h2>
<p>This step is nearly identical to the last. This time we create a database
named <em>icingaweb2</em> and grant permissions to the user named
<em>icingaweb2_admin</em>.</p>
<pre><code>mysql -u root -e "CREATE DATABASE icingaweb2;GRANT ALL ON icingaweb2.* TO 'icingaweb2_admin'@'localhost' IDENTIFIED BY '<em>changeme</em>'; FLUSH PRIVILEGES;</code></pre>
<p>Again we will need to import required schema into the database.</p>
<pre><code>mysql -u root icingaweb2 </usr/share/icingawbe2/etc/schema/mysql.schema.sql</code></pre>
<p>In this step we create the initial admin user that will be used to login
to the web interface. As is, this would create a user named <em>admin</em>
with the password <em>changme</em>. You should at least change the password.</p>
<pre><code>passhash="$(php -r "echo password_hash(\"<em>changeme</em>\", PASSWORD_DEFAULT);")"
mysql -u root -e "USE icingaweb2; INSERT INTO icingaweb_user (name, active, password_hash) VALUES (\"<em>admin</em>\", 1, \"$passhash\"); FLUSH PRIVILEGES;"</code></pre>
<h2>Create Icinga Director Database</h2>
<p>Here we create the database for Director. Director will require more
configuration later, so for now we will just be creating the database.</p>
<pre><code>mysql -u root -e "CREATE DATABASE director CHARACTER SET 'utf8'; GRANT ALL on director.* TO 'director'@'localhost' IDENTIFIED BY '$director_password';FLUSH PRIVILEGES;"</code></pre>
<h2>Setup Icinga2 API</h2>
<p>Run the following command to initialize the Icinga API.</p>
<pre><code>icinga2 api setup</code></pre>
<p>And then restart Icinga to apply the changes.</p>
<pre><code>systemctl restart icinga2</code></pre>
<h2>Configure Web Server</h2>
<p>In this section we will configure the web server for accessing
Icinga's web interface and Director configuration tool.
This tutorial will use nginx but apache could be used as well.
We'll start by installing the necessary packages.</p>
<pre><code>apt install nginx php-fpm</code></pre>
<p>Then we need to create the site configuration file.<p>
<pre><code><strong>/etc/nginx/sites-available/icingaweb2.conf</strong>
server {
listen 80;
server_name <em>monitoring.example.com</em>
location ~ ^/icingaweb2/index\.php(.*)$ {
fastcgi_pass unix:/var/run/php/php-fpm.sock;
fastcgi_index index.php;
include fastcgi_params;
fastcgi_param SCRIPT_FILENAME /usr/share/icingaweb2/public/index.php;
fastcgi_param ICINGAWEB_CONFIGDIR /etc/icingaweb2;
fastcgi_param REMOTE_USER $remote_user;
}
location ~ ^/icingaweb2(.+)? {
alias /usr/share/icingaweb2/public;
index index.php;
try_files $1 $uri $uri/ /icingaweb2/index.php$is_args$args;
}
<em># Not strictly necessary but allows you to get to icinga without
# specifying /icingaweb2 in the URL.</em>
location = / {
return 302 http://$host/icingaweb2;
}
}</code></pre>
<p>And then restart nginx to pick up the changes.</p>
<pre><code>systemctl restart nginx</code></pre>
<p>At this point we are done with the Icinga setup module and so we
can disable it.</p>
<pre><code>icingacli module disable setup</code></pre>
<h2>Write Configuration Files</h2>
<p>In this section we will write several configuration files. Icinga uses
the INI format for its web interface configuration files.</p>
<p>In this first file we tell Icinga about the various resources it should have
access to. These resources are the three databases created previously.
Replace the password in each section with the corresponding password you set
for that database earlier.</p>
<pre><code><strong>/etc/icingaweb2/resources.ini</strong>
[icinga2]
type = "db"
db = "mysql"
host = "localhost"
port = ""
dbname = "icinga2"
username = "ido_admin"
password = "<em>ido password</em>"
charset = ""
use_ssl = "0"
[icingaweb2]
type = "db"
db = "mysql"
host = "localhost"
port = ""
dbname = "icingaweb2"
username = "icingaweb2_admin"
password = "<em>ido password</em>"
charset = ""
use_ssl = "0"
[director]
type = "db"
db = "mysql"
host = "localhost"
port = ""
dbname = "director"
username = "director"
password = "<em>director password</em>"
charset = "utf8"
use_ssl = "0"
</code></pre>
<p>This file controls the authentication settings for the web interface.
Here we tell Icinga to look at the icingaweb2 database for
authentication purposes.</p>
<pre><code><strong>/etc/icingaweb2/authentication.ini</strong>
[icingaweb2]
backend = "db"
resource = "icingaweb2"</code></pre>
<p>Now we tell icinga which users should have admin permissions.
If you changed the username value from <em>admin</em> previously, be sure to update
it here.</p>
<pre><code><strong>/etc/icingaweb2/roles.ini</strong>
[admins]
users = "<em>admin</em>"
resource = "icingaweb2"</code></pre>
<p>Enable the web interface monitoring module.</p>
<pre><code>icingacli module enable monitoring</code></pre>
<p>Then write the configuration file pointing the monitoring module to the
monitoring database.</p>
<pre><code><strong>/etc/icingaweb2/modules/monitoring/backends.ini</strong>
[icinga]
type = "ido"
resource = "icinga2"</code></pre>
<p>Here we configure Icinga to use the API for communication.
You will need to get your unique API password generated during the API setup from
from <strong>/etc/icinga2/conf.d/api-users.conf</strong>.
<em>hostname</em> should be the FQDN of the server.</p>
<pre><code><strong>/etc/icingaweb2/modules/monitoring/commandtransports.ini</strong>
[icinga2]
transport = "api"
host = <em>hostname</em>
port = "5665"
username = "root"
password = "<em>api password</em>"</code></pre>
<p>Lastly, tell Icinga to protect variables with potentially sensitive values.</p>
<pre><code><strong>/etc/icingaweb2/modules/monitoring/config.ini</strong>
[security]
protected_customvars = "*pw*,*pass*,*community*"</code></pre>
<h2>Configure Director</h2>
<p>This section will cover configuring Director configuration tool.</p>
<p>Create Director module configuration directory.</p>
<pre><code>mkdir -p /etc/icingaweb2/modules/director</code></pre>
<p>Write the Director configuration file.</p>
<pre><code><strong>/etc/icingaweb2/modules/director/config.ini</strong>
[db]
resource = "director"</code></pre>
<p>Enable Director module and run the initial migration.</p>
<pre><code>icingacli module enable director
icingacli director migration run</code></pre>
<p>Write Director kickstart configuration file.</p>
<pre><code><strong>/etc/icingaweb2/modules/director/kickstart.ini</strong>
[config]
endpoint = "<em>hostname</em>"
username = "root"
password = "<em>api password</em>"</code></pre>
<p>Kickstart Director, then render and deploy the configuration.</p>
<pre><code>icingacli director kickstart run
icingacli director config render
icingacli director config deploy</code></pre>
<p>Director is setup at this point so we will shred the unneeded configuration
file containing sensitive information.</p>
<pre><code>shred -uz /etc/icingaweb2/modules/director/kickstart.ini</code></pre>
<h2>Login to your Monitoring Instance</h2>
<p>You are now ready to login to your monitoring instance with the admin
user created previously. Open a web browser and go to
http://<em>hostname</em>/icingaweb2. You should see a screen similar to this:</p>
<a href=../images/icinga-login.png><img src=../images/icinga-login.png alt="Icinagweb2 Login Screen"></a>
<h2>Next Steps</h2>
<p>In the following articles we will go through setting up Icinga2 agents on servers, and configure your monitoring instance through Icinga Director.</p>
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