How to locate a failed disk on a NetApp Filer

If you work on the NetApp Filers, you must have come across a situation where you get an AutoSupport notification from NetApp filer that a certain disk on the shelf has failed, this does not mean any interruption to the Filer serving data as usually it is equipped with spare disks which take over. However, it’s prudent to replace the failed disk as soon as possible so you are not left with degraded performance issue in case another disk fails. The auto support notification would usually tell you the disk and shelf number of the disk which has failed (for example 2b.32) but on the shelf, how can you be absolutely sure that you are replacing the right disk?

When a disk fails on a NetApp Filer shelf, you can usually see that the LED turn yellow on the particular disk, however this is not always the case, or sometimes if two disks can show the yellow LED. The best thing to do at this time is to do a LED blink test. It is a simple test which can be used on Data OnTap versions 6 and higher, which uses a command to turn a LED on and off on any desired disk.

Here is how to do it::

- SSH to the NetApp Filer console

- Change to advanced mode by giving the command "priv set advanced" (without quotes)

- If you are trying to find blink disk 0a.14, give the command "blink_on 0a.14" (without quotes)

- After testing, to turn off blinking, you can give the command "blink_off 0a.14"

Note that in certain circumstances, if the disk is physically damaged and the led light on it won't turn on, you can blink the lights on its adjacent disks (in this example 0a.13 and 0a.15) and locate the disk in the middle