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I am working a script to create a raid5 array. The question is how to put the command in a if (to see if the command succeeded), and when the script ask to continue creating array it will auto say yes.

Here is the command:

mdadm --create --verbose /dev/md0 --level=5 --raid-devices=3 /dev/sdc1 /dev/sdd1 /dev/sde1 --spare-devices=1 /dev/sdf1
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This bash script should work, however I did not test it. It does literally check if last command status is different then 0 (OK) if not then (FAIL).

mdadm --auto=yes ...
if [ $? -eq 0 ]; then
    echo OK
    echo FAIL

Read the manual here: it says more about parameters and the flag --auto. Also it should tell you more about return status codes, so you can add the case scenarios to your bash script.

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I get this fault: mdadm: --auto does not set the mode, and so cannot be the first option. FAIL – user3185936 Feb 16 '14 at 15:24
Try moving the --auto flag after the --spare-devices=1. Synopsis for that command is: mdadm [mode] <raiddevice> [options] <component-devices> – NeverEndingQueue Feb 16 '14 at 15:29
The scripts runs now, but it still asks me if I want to continue creating array. So that means that --auto=yes didn't work. – user3185936 Feb 16 '14 at 15:31
I don't have opportunity to test it, so I am doing it blind, however the point is to put option between your raiddevice and compontent-devices. Assuming that your raiddevice is the /dev/md0 and your component devices are: /dev/sdc1, /dev/sdd1, /dev/sde1 and /dev/sdf1 you need to add option --auto for e.g after the --raid-devices flag. Also you should move: --spare-devices following the same logic (as it's possibly ignored right now). Give it a try. If it does not work then someone more familiar with that command should be able to help. – NeverEndingQueue Feb 16 '14 at 15:46
Thank you, for your help and time! I have tried different methods of placing the auto flag. It's not looking good. Hopefully someone who have encountered this fault will help. – user3185936 Feb 16 '14 at 15:53

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