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Create a RAID-1 of the boot disk and a new disk

Hello,
I had one disk before (/dev/sda) with two partitions, one swap and one ext3 where all the files are located. Now I've added a second disk (/dev/sdb) and want to create a RAID-1 disk of the two disks (based on the current /dev/sda disk). How can I do that? I've installed mdadm but I can't figure out how to create the RAID-1 since I'm running the system on /dev/sda.

Best Regards
Oskar R

partition your /dev/sdb similar to /dev/sda. I personally would use fdisk

Code:

fdisk /dev/sdb

Another user on here, i_grok, helped me and also mentioned that you could use the sfdisk command, but I haven't tried it. It's suppose to replicate the partitions to the other drive. For example,

Code:

sfdisk -d /dev/sda1 | sfdisk /dev/sdb1

After, create the initial /dev/md0, /dev/md1, etc...

Code:

mdadm --create --verbose /dev/md0 --level=1 --raid-devices=2 /dev/sda1

mdadm --create --verbose /dev/md1 --level=1 --raid-devices=2 /dev/sda2

etc...

Now sync up /dev/sdb with /dev/sda

Code:

mdadm /dev/md0 --add /dev/sdb1

mdadm /dev/md1 --add /dev/sdb2

etc...

check the progress of the syncing

Code:

cat /proc/mdstat

You can always find more information

Code:

man mdadm

I could be wrong about all this, though. I've only done the software RAID once or twice and am recalling this from memory.

You can also google up this question as there are tons of articles online that will explain this

OK, I'll try that, however, I created /dev/md0 and /dev/md1 now by misstake when I tried another guide and now I can't remove them... They are (or should be) based on /dev/sdb1 and /dev/sdb2. How can I remove /dev/md0 and /dev/md1 now to be able to continue without reinstalling the system again?

try

Code:

mdadm /dev/md0 --manage --stop 

mdadm /dev/md0 --manage --remove 

etc...