david90

when I exec

RAID_FAILDEV_CHK=$(mdadm --detail /dev/md0 | grep -Z "Failed Devices")

RAID_FAILDEV_CHK will have the string "Failed Devices : 0"


The problem is that if I do

if [ "$RAID_FAILDEV_CHK" = "Failed Devices : 0" ]

I get false. Why? I think there is a trailing return char in variable $RAID_FAILDEV_CHK. If so, how do I remove that char?

david90

I found the problem.

The command

RAID_FAILDEV_CHK=$(mdadm --detail /dev/md0 | grep -Z "Failed Devices")

will put " Failed Devices : 0" in variable RAID_FAILDEV_CHK. Notice the space in front of "Failed"

This is why

if [ "$RAID_FAILDEV_CHK" = "Failed Devices : 0" ]

will always return false.

Can somebody tell me why there's a space in front of "failed"?

secondmouse

man grep (hint: should be -o if you want RAID_FAILDEV_CHK to contain exactly the phrase "Failed Devices).

in short, you used the wrong grep option.