A5158A HBA

[Karl Myers_1]

Could someone advise how to check whether the HBA is configured for I/O or Active / Passive mode and what impact each might have.

Also I need to confirm whether dual paths are being utilised.
vgdisplay -v gives me the PV output with alternate links......

[Eugeny Brychkov · Accepted solution]

Active/Passive mode is not a feature of FC HBA. It should be feature of disk array like FC60. To check HBA state use fcmsutil command
fcmsutil /dev/tdX
where X is an interface number (see 'ioscan -fn').
If vgdisplay displays alt paths then they should be already configured. If you wish you can test simply unplugind cables i.e. interrupting primary path, although please do it when SAN is not in production... to be safe and watch 'tail -f /var/adm/syslog/syslog.log' for coming events about path failures and restorations
Eugeny

[Bernhard Mueller]

Karl,

LVM only shows you the pvlinks and if the primary fails (and only then) it will utilize the alternate link. If that happens you see messages in syslog.

So to enable active/active connections you need some s/w on your storage box like EMC's PowerPath or XP AutoPath or whatever it may be called.

You can test your disk IO using iostat:
assume you have a filesystem on /dev/vgtest/lvol1 then start
# dd if=/dev/vgtest/rlvol1 of=/dev/null bs=1024k
then run
# iostat 1 1000
if the filesystem mounted from /dev/vgtest/lvol1 is on disk /dev/dsk/c1t1d3 and your vgdisplay -v says that c3t1d3 is an alternate path to c1t1d3
you see high IO numbers for c1t1d3 and 0 for c3t1d3 if you do *not* use PowerPath or similar.

Regards
Bernhard