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+<!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>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>
+<p>
+<hr>
+Consider <a href=../donate.html>donating</a> if this article was useful.
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diff --git a/articles/mdadm-raid.html b/articles/mdadm-raid.html new file mode 100644 index 0000000..dd2a014 --- /dev/null +++ b/articles/mdadm-raid.html
@@ -0,0 +1,120 @@
	1	<!DOCTYPE html>
	2	<html lang=en>
	3	<head>
	4	<title></title>
	5	<meta charset="utf-8"/>
	6	<link rel="shortcut icon" href="favicon.ico"/>
	7	<link rel='stylesheet' href='../style.css'/>
	8	<meta name="viewport" content="width=device-width, initial-scale=1">
	9	</head>
	10	<body>
	11	<header><h1>Linux Software RAID</h1></header>
	12	<main>
	13	<p><strong>mdadm</strong> is a tool that allows for creation and
	14	management of software RAID arrays on Linux. Creating an array
	15	is a rather straightforward process.</p>
	16
	17	<h2>Install packages</h2>
	18	<p>The only package needed is mdadm itself</p>
	19	<pre><code>apt install mdadm</code></pre>
	20
	21	<h2>Partition disks</h2>
	22	<p>We'll need to parition the disks to be used in the array before
	23	creating it. This isn't anything complicated, we will just be
	24	creating a single partition using all the space on each disk.</p>
	25
	26	<p>Use <strong>lsblk</strong> to get a list of disks attached to your system.</p>
	27
	28	<img src=../images/raid/lsblk.png alt="lsblk command">
	29
	30	<p>Then use <strong>fdisk</strong> to edit the partition table of the
	31	first disk. In my case this would be <strong>/dev/sdb</strong>.
	32	Be sure that you are selecting the correct disk as selecting the
	33	wrong one can result in data being lost.</p>
	34
	35	<pre><code>fdisk /dev/sdb</code></pre>
	36
	37	<p>Use <strong>g</strong> to create a new GUID partition table.
	38	Use <strong>n</strong> to create a new partition, and then just press
	39	enter at all of the prompts to accept the defaults. Finally use
	40	<strong>w</strong> to write the changes. You can use lsblk again
	41	to verify the change and you should see that /dev/sdb now has a
	42	partition <strong>/dev/sdb1</strong>.</p>
	43
	44	<img src=../images/raid/fdisk.png alt="fdisk command">
	45
	46	<p>Repeat this process for your other disks before continuing.</p>
	47
	48
	49	<h2>Create the array</h2>
	50	<p>Creating the array is done with a single command, but takes just a
	51	bit of planning.</p>
	52	<ul>
	53	<li>Define an ID for the array, which is just a
	54	number identifier. I use <em>0</em> in the command.</li>
	55	<li>Determine the RAID level you want to use. I am going to
	56	use RAID5 in this example. The argument to --level is the
	57	number of the RAID level</li>
	58	<li>Determine the devices that will be used in the array.
	59	Somewhat contrary to the argument name, these devices
	60	will actually be the partitions of the disks and not the
	61	disks themselves. In the command, give the number of
	62	partitions (<em>3</em>) and then a space-separated list of the
	63	partitions that will be active in the array
	64	(<em>/dev/sdb1 /dev/sdc1 /dev/sdd1</em>).</li>
	65	<li>If you want to have any spare devices in the array you
	66	will define them with the --spare-devices argument. These are
	67	defined in the exact same way as the active RAID devices. In
	68	the example I use <em>1</em> spare <em>/dev/sde1</em>. Spare
	69	devices are hot-spares that will automatically be inserted into
	70	the array if one of the disks fails.</li>
	71	</ul>
	72
	73	<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>
	74
	75	<p>After creating the array run the following command to get details
	76	and the status of the array. It will take a bit to initialize the
	77	array, you will know this is done when the state is clean. You do not
	78	need to wait for the array to completely intialize to continue.</p>
	79
	80	<pre><code>mdadm --detail /dev/md<em>0</em></code></pre>
	81
	82	<p>Take note of the UUID and name values as we will need them in the
	83	next step.</p>
	84
	85	<p>Before moving on we need to make a filesystem on the array. I'm
	86	going to make a simple EXT4 filesystem here.</p>
	87
	88	<pre><code>mkfs.ext4 /dev/md<em>0</em></code></pre>
	89
	90
	91	<h2>Configuration Files</h2>
	92
	93	<p>Open the mdadm configuration file at
	94	<strong>/etc/mdadm/mdadm.conf</strong> and append this line. Replace
	95	<em>uuid</em> and <em>name</em> with the values you got when running
	96	mdadm --detail, replace <em>0</em> whatever ID you chose.</p>
	97
	98	<pre><code>ARRAY /dev/md<em>0</em> metadata=1.2 UUID=<em>uuid</em> name=<em>name</em></code></pre>
	99
	100	<p>Optionally, create an <strong>/etc/fstab</strong> entry for
	101	automounting of the array. Replace /mnt/raid with the directory
	102	where you want to mount the array. If you made a filesystem other than
	103	ext4 make sure to change that value.</p>
	104
	105	<pre><code>/dev/md<em>0</em> /mnt/raid ext4 defaults 0 1</code></pre>
	106
	107	<p>
	108	<hr>
	109	Consider <a href=../donate.html>donating</a> if this article was useful.
	110	<a class=qr href=../images/bitcoin.png>[BTC]</a>
	111	</p>
	112	</main>
	113	<footer>
	114	<a href=../kb.html>Knowledge Base</a>
	115	<br>
	116	<a href=../index.html>www.chudnick.com</a>
	117	</footer>
	118	</body>
	119	</html>
	120