topic Re: Ioscan in Operating System - HP-UX

Ioscan

Andrew medhurst1 — Tue, 17 Jun 2008 14:54:08 GMT

has anyone seen ioscan hang and not return anything, just started to happen for no reason.
regards
andrew

Re: Ioscan

Pete Randall — Tue, 17 Jun 2008 14:58:05 GMT

I've seen it take a long time but never completely hang, unless there is a problem that is preventing it from scanning a device.

Pete

Re: Ioscan

Pete Randall — Tue, 17 Jun 2008 14:59:07 GMT

I should add - check dmesg and syslog to see if you can spot any problems that might be causing the hang.

Pete

Re: Ioscan

Adam Winebaugh — Tue, 17 Jun 2008 15:00:54 GMT

The only time I have ever had it completely hang is when I had a corrupt /dev filesystem. I would check syslog to see if there are any errors being generated.

Re: Ioscan

Andrew medhurst1 — Tue, 17 Jun 2008 15:09:20 GMT

it has eventually returned but is taking a long time, any ideas?
regards
andrew medhurst

Re: Ioscan

Pete Randall — Tue, 17 Jun 2008 15:21:32 GMT

The fact that this "just started to happen for no reason" bothers me. I would think that something must have changed.

In any case, does just scanning the kernel structures speed things up ("ioscan -kfn" vs. "ioscan -fn")?

Pete

Re: Ioscan

Torsten. — Tue, 17 Jun 2008 15:31:26 GMT

I've seen it hang with failing scsi drives and scanning for a long time on large SANs without assigned LUNs.

Re: Ioscan

Anka — Tue, 17 Jun 2008 17:33:57 GMT

How long was it scanning?
Do you have SAS devices on the system? There is a delay when scanning sas logical volumes.
Are there too many devices attached to the system?
As already advised check the syslog/dmesg.
If no error you can try scanning HW path after HW path (-H option) to see where is the delay...

Re: Ioscan

Andrew medhurst1 — Wed, 18 Jun 2008 08:59:03 GMT

thanks for the help found problem, for some reason the server is seeing a san disk which is causing the issue and there are not supposed to be any san disk on the server so i am investigating but an happy as i know have resolution.
regards
Andrew

Re: Ioscan

Andrew medhurst1 — Wed, 18 Jun 2008 09:00:18 GMT

thanks