DokuWiki » Infrastructure » Operating System » CentOS 9

h1. Howto mdadm

lsblk is your best friend

<pre><code class="shell">

lsblk

</code></pre>

we are going to use partitions as base for the raid

h2. create Linux RAID partitions

<pre><code class="shell">

fdisk /dev/nvme0n1

</code></pre>

h3. create new GPT disklabel

<pre>

g

</pre>

h3. create new partion

<pre>

n

</pre>

h3. change type to Linux RAID

<pre>

t

</pre>

<pre>

29

</pre>

repeat for all drives e.g. @/dev/nvme0n1@ and @/dev/nvme1n1@

check with lsblk

h2. create Raid

<pre><code class="shell">

mdadm --create /dev/md20 --level=1 --raid-devices=2 /dev/nvme0n1p1 /dev/nvme1n1p1

</code></pre>

check with lsblk

h2. create filesystem on Raid

<pre><code class="shell">

mkfs.xfs /dev/md20

</code></pre>

h2. update mdadm.conf

<pre><code class="shell">

mdadm --detail --scan

</code></pre>

add the ARRAY info in @/etc/mdadm.conf@

should look similar to this

<pre>

# JKE 2024-09-17

#ARRAY /dev/md20 metadata=1.2 name=hostXX.example.com:20 UUID=d80d7e3a:833baf6d:a428f02d:6f27f791

ARRAY /dev/md20 UUID=d80d7e3a:833baf6d:a428f02d:6f27f791

</pre>

h2. check raid

<pre><code class="shell">

cat /proc/mdstat

</code></pre>