LPAR freezes after switching of storage (lpar is mirrored)

UNIX AIX
1

Hi all,

I have the following configuration

2 ds3524 storage disk systems located over 2 locations
2 P720 server located over 2 locations

DS3524 are connected to san switch.
Each vio server has 1 fc adapter attached to a san switch.

per p720 server 2 virtual io servers. Vio 1 has 1 lun from 1 ds3524, Vio 2 has 1 lun from the other ds3524
On the lpar we use LVM mirroring.

The problem:

When we halt 1 DS3524 the lpar freezes for about 30 seconds and then is again available.
Is this normal behaviour? When i shutdown 1 vio server , everything on the lpar is ok , no freeze.

Any ideas ?

thx MarkieMark

2

Do you have these attributes set on your fscsi devices on your VIO servers?

vio2:/home/padmin:# lsattr -El fscsi0 | egrep "fc_err_recov|dyntrk"
dyntrk       yes       Dynamic Tracking of FC Devices        True
fc_err_recov fast_fail FC Fabric Event Error RECOVERY Policy True
vio2:/home/padmin:#

I also set these attributes on the disks themselves on the VIO servers:

vio2:/home/padmin:# lsattr -El hdisk5 | egrep "rw_timeout|q_type"
q_type          simple                           Queue TYPE                       True
rw_timeout      30                               READ/WRITE time out              True
vio2:/home/padmin:#

To be honest, I can't remember what they do, but I'm sure I had a good reason to set them this way when I first configured them.

3

Hi,

Yes, these settings i have on the fc adapter

Markiemark