Those with LINUX based NAS + RAID

[billabong132]

Those with linux powered raid box nas'.


What do you use to monitor drive health?

Most raid cards come with a gui for windows that alerts you/sends emails when a drive drops out of the array.

However, cars claiming linux support usually just have a kernel driver, and nothing else. How do you manage the array to make sure you aren't running on your last drive?

 

[billabong132]

?

 

[Sharaz Jek]

3ware cards have a web interface (along with the kernel module) that works in linux (at least, mine does).

 

[unhappy_mage]

$ man mdadm

MONITOR MODE
       Usage: mdadm --monitor options... devices...

       This  usage causes mdadm to periodically poll a number of md arrays and
       to report on any events noticed.  mdadm will never exit once it decides
       that  there  are  arrays to be checked, so it should normally be run in
       the background.

       The result of monitoring the arrays is the generation of events.  These
       events are passed to a separate  program  (if  specified)  and  may  be
       mailed to a given E-mail address.

So make a startup script (varies by distro) that essentially runs:
mdadm --monitor --scan --mail you@localhost &
or whatever email address you prefer. SMTP will have to be set up, of course, if you want to go off-host.

 

[allbad]

i like linux software raid, so i can look at /proc/mdstat for this info:

# cat /proc/mdstat
Personalities : [raid0] [raid1] [raid5]
md1 : active raid1 sdb2[1] sda2[0]
      4096448 blocks [2/2] [UU]

md2 : active raid0 sdb3[1] sda3[0]
      4096000 blocks 256k chunks

md3 : active raid0 sdb4[1] sda4[0]
      181180928 blocks 256k chunks

md4 : active raid5 sdf1[3] sde1[2] sdd1[1] sdc1[0]
      732594816 blocks level 5, 64k chunk, algorithm 2 [4/4] [UUUU]

md0 : active raid1 sdb1[1] sda1[0]
      20482752 blocks [2/2] [UU]

unused devices: <none>

# df -h
Filesystem            Size  Used Avail Use% Mounted on
/dev/md0               19G  8.0G   11G  45% /
/dev/md4              677G  456G  187G  71% /home
/dev/md3              168G  417M  159G   1% /tmp
/dev/md1              3.8G  2.3G  1.4G  64% /var

The UUUU indicates a healty array, otherwise you'd see something like UU_U to indicate a failure. You'll also see a (F) next to the failed partition. I just keep a tail on "/var/log/messages | grep 3w" and watch for any hickups.

if you've got a 3ware card (highly suggested especially for linux) then you can also download their 'tw_cli' utility which allows you to view hardware RAID status, and you can also rebuild arrays etc... basically anything you can do from the 3ware BIOS screen when booting.