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How do I keep mdadm from renaming my RAID array upon reboot?

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http://serverfault.com – So I have a system (a large instance running ubuntu-11.10 on Amazon EC2) where I've done something like mdadm --create bigdata --level 0 --raid-devices=2 /dev/xvdb /dev/xvdc I get a RAID device of two disks (ephemeral instance stores) at /dev/md/bigdata. Yay. reboot. I now have a RAID device of two disks at ip-10-811-498-737:bigdata. (ip anonymized). This is kind of obnoxious. I'd like to set up the RAID in a user-data install script, and set it up with a known device name, and then mount things from /etc/fstab - but the device name changes between creation and reboot, which makes this (HowTos)

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Submitted by xskl on 06/26/2012 – Made popular on 06/26/2012

Stories similar to How do I keep mdadm from renaming my RAID array upon reboot?

I want to set up software RAID-1 on my Ubuntu system, and found this example of an /etc/raidtab:

raiddev /dev/md0 raid-level 1 nr-raid-disks 2 nr-spare-disks 0 persistent-superblock 1 device /dev/sdb1 raid-disk 0 device /dev/sdc1 raid-disk 1

I would however like the path to the raid device to be /raid.

Hi All,

I have been trying to create a USB RAID 5 using mdadm tool on Joli OS 1.2 (Ubuntu) but with no luck. I cannot even get pass the creation of array device (/dev/md0) and superblock.

After a restart which stalled, I did a hard reboot and now mdadm can't see the RAID 6 array anymore, LVM can't find the volume which was on that raid array.

Trying to set up a RAID 1 year 10 weeks ago

I'm trying to create a Raid array and these are the errors I keep getting.

I am building a home server with raid 5. I first set up the system to boot from compact flash. After i got that working I tried to create the raid 5 array. All disks are new and have no data on them. I used the following command to create the array:

mdadm --create --verbose /dev/md0 --level=5 --raid-devices=3 /dev/sd[bcd]1

After this I ran 'watch cat /proc/mdstat'.

So this is the first time I'm using RAID and I started with a 2x2TB RAID-5 array since I only had two disks at the time.

Hi

No longer able to access my raid, not sure what caused this, but im not able to start it either, help!

mdadm -E /dev/md0 mdadm: no md superblock detected on /dev/md0

mdadm -D /dev/md0 mdadm: md device /dev/md0 does not appear to be active

cat /proc/mdstat shows Personalities : [linear] [multipath] [raid0] [raid1] [raid6] [raid5] [raid4] [raid10]

md0: inactive sdb1[2](S) sdc1[1](S)

I have a 6 device raid 5 array which had 1 disk go bad and then due to a power outage, the machine shutdown and when it started all the disks were showing up as spares with the following mdadm -E output.

/dev/sda5: Magic : a92b4efc Version : 1.2 Feature Map : 0x0 Array UUID : b480fe0c:c9e29256:0fcf1b0c:1f8c762c Name : GATEWAY:RAID5_500G Creation Time : Wed Apr 28 16:10:43 2010

So my computer has four 1.5 TB drives installed. Up until recently, these drives existed in two RAID1 configurations of 3 TB.

Recently I decided to create one large RAID5 device out of them instead.