Wednesday, September 30, 2009

How to enable powerpath failed path in a faster way

By unplug one of the Fiber cable to simulate FC HBA failure, the result as expect:



[root@VMXDB01 ~]# powermt display
Symmetrix logical device count=39
CLARiiON logical device count=0
Hitachi logical device count=0
Invista logical device count=0
HP xp logical device count=0
Ess logical device count=0
HP HSx logical device count=0
==============================================================================
----- Host Bus Adapters --------- ------ I/O Paths ----- ------ Stats ------
### HW Path Summary Total Dead IO/Sec Q-IOs Errors
==============================================================================
3 qla2xxx optimal 39 0 - 0 0
4 qla2xxx failed 39 39 - 0 39


[root@VMXDB01~]# powermt display dev=emcpowera
Pseudo name=emcpowera
Symmetrix ID=0009899012321
Logical device ID=0141
state=alive; policy=SymmOpt; priority=0; queued-IOs=0
==============================================================================
---------------- Host --------------- - Stor - -- I/O Path - -- Stats ---
### HW Path I/O Paths Interf. Mode State Q-IOs Errors
==============================================================================
3 qla2xxx sdbe FA 7aA active alive 0 0
4 qla2xxx sdce FA 9aA active dead 0 1


After put back the fiber cable, it takes 5 minutes to detect this recovery action and change the state to "alive".

How to make it faster? the answer is to use "powermt enable hba=#hba" to enable the hba (path) manually. Here #hba is referring to the first column of the output (hba is 3 or 4)


[root@VMXDB01 ~]# powermt enable hba=4