The update of an SR's firmware when it is providing elements for an EM mirror should be considered a scheduled "downtime event." In a Linux environment the following procedure is recommended:
Download the latest SR firmware release from the SR support page.
Follow the instructions in Appendix "C" of the SR software user manual to update the SR's firmware, however do not reboot the SR after running 'update' at the SR console.
As an optional step, the value of /sys/module/aoe/parameters/aoe_deadsecs on the Linux initiator can be increased to allow more time for the following steps. This is the time in seconds (default = 180) that the AoE initiator will wait before declaring a disappeared target "dead." For example:
Next, offline the EM mirrors for which the SR being updated is providing the mirror elements. This step stops all traffic to the mirror, preventing the EM from declaring the SR's LUN missing and putting the mirror in a degraded state:
EM 320> lsmir
LUN ONLINE TARGETA TARGETB SLENGTH PARTS LABEL
1 ON 20.1 21.1 5,860,575,357 n/a
EM 320> offline 1
EM 320> lsmir
LUN ONLINE TARGETA TARGETB SLENGTH PARTS LABEL
1 OFF 20.1 21.1 5,860,575,357 n/a
EM 320>
Reboot the SR on which 'update' was run in step 2.
Immediately after the SR has finished booting and the prompt has returned, online the EM mirror again:
EM 320> online 1
EM 320> lsmir
LUN ONLINE TARGETA TARGETB SLENGTH PARTS LABEL
1 ON 20.1 21.1 5,860,575,357 n/a
EM 320>
If you increased the value of /sys/module/aoe/parameters/aoe_deadsecs on the AoE inititator in step 3 above, you should now restore the former value. Remember that the default is 180 seconds:
We have hints that will help you get the fastest and best support we can
provide at our Fast Support HOWTO. If you still need assistance with your CORAID EtherDrive Mirror please send the information requested at the Fast Support HOWTO to support@coraid.com.