Many use and love Equalogic SANs in their virtual environments. I wanted to write up a quick post on how to see if any of your hard drives inside your Equalogic have experienced or are experiencing drive errors. This can be helpful if you suspect a hard drive is having issues or noticing some performance degradation in your environment and have looked elsewhere to no avail.
In order to check Equalogic SAN hard drives for errors, we need to SSH into the Equalogic using the grpadmin user account the same as you would updating firmware on your unit. Using your favorite terminal emulator, simply SSH into the controller IP of the specific SAN or group controller IP if only one unit.
After you connect with SSH, you will enter your grpadmin credentials to authenticate and should get to a prompt. After you login, you will need to enter the following command:
su ex sh
As you are warned, this takes you into the “tech support command console” which you want to use with caution.
Now to look at the state and counters of your Equalogic disks, you enter the command
The above command will list the disks, the error counters and their current status for troubleshooting purposes. You will note the “SpunDown” drives which are the hot spares inside our system.
Using the support command needs to be issued with extreme caution as you can imagine, very bad things can happen if not used correctly. However, viewing disk statuses is harmless if used carefully and can be a good troubleshooting tool if experiencing hard drive issues or performance oddities as another sanity check.