disk i/o tuning for wait/delay

[Dan Matlock_1]

We have an issue with our xiotech SAN whereby on a crontoller failover test, we received i/o errors temp. (which recovered), which caused sybase ase to report errors, which then caused an app to fail... We adjusted the wait times for the emulex cards, but didn't work. So again the question posed to me was: Is there any other disk i/o tunables that could suppress the i/o errors or slow them down for the split second the SAN controller fails over???

[Joseph Loo]

hi dan,

may i know the error specified, i.e. messages, logs?

u may also like to read this:

http://www1.itrc.hp.com/service/cki/docDisplay.do?docLocale=en_US&docId=200000080062388

regards.

[Steven E. Protter]

Shalom Don,

There is an entire lvm setup concept/method called alternate links(PVLINKS).

If you have two paths to the disk, you should be able to avoid this completely.

If however you only have one path to the disk your options are limited to shutting down the application and sybase.

SEP

[Dan Matlock_1]

Thanks for the feedback, and unfortunetly my company setup the servers with 1 x fiber drop so no alternate links....