LVM I/O errors while one VIO down in Dual VIO configuration

[polani]

Guys,

I have a dual VIO setup where two VIO servers are accessing SAN storage ( IBM DS8100 ) through dual ports HBA each.
SDDPCM is installed on each VIO servers and they are getting eight paths to each disk.
Every thing seems Ok unless i shutdown one of the VIO. SEA faiolver happened successfully , but disks failover did not happen so successfully and client Lpars almost hang . I had to restart client Lpars forcefully through HMC to recover these Lpars ( still one VIO was down).

All client Lpars have vscsi devices mapped to host adapters of both VIO servers. Quite surprisingly, exactly same setup is working well at main site, but with DS8300.

Errors which i get on client Lpars are something related to LVM I/O errors;Even shutdown command does not work at all , start giving strange errors on /tmp & /var & /... so every thing freezes.

By the way , all client Lpars are booting from SAN and i dont have any MPIO drivers on client Lpars ( as per my assumption, these are just SCSI disks to client Lpars)...

Now what should i check ? any failover settings for HBA adapters? Any thing else on dual VIO servers to be done to failover to happen smoothly?

All disks have scsi_reserve set to no_reserve!!

Please advice



Here comes polani Once again!!!

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[chgwhat]

After you have installed AIX on the client logical partition, check for MPIO by running the following command:

lspath

You see results similar to the following:

Enabled hdisk0 vscsi0
Enabled hdisk0 vscsi1

If one of the Virtual I/O Server logical partitions fails, the results of the lspath command look similar to the following:

Failed hdisk0 vscsi0
Enabled hdisk0 vscsi1

Unless the hcheck_mode and hcheck_interval attributes are set, the state will continue to show Failed even after the disk has recovered. To have the state updated automatically, type chdev -l hdiskx -a hcheck_interval=60 -P. The client logical partition must be rebooted for this change to take effect.

Tony ... aka chgwhat

When in doubt,,, Power out...

 

[bi]

Did you set path priority on the LPARs?