topic Disconnect SCSI from Itanium box without turning off? in Operating System - HP-UX

Disconnect SCSI from Itanium box without turning off?

Kalin Evtimov — Fri, 09 Feb 2007 07:53:29 GMT

A few time ago an HP-guy told me, that I can plug any SCSI devices into Itanium boxes without having to turn them off (not like RISC machines).

As I have to disconnect an SCSI Array from an productive Itanium box, I was wondering if this would work too without causing errors.

Please let me know, if You have some information.

Greetings!

Kalin

Re: Disconnect SCSI from Itanium box without turning off?

Torsten. — Fri, 09 Feb 2007 08:08:55 GMT

Hi,

this might work 99 or even 999 times without problems, but anyway - it is recommended to never open a powered SCSI bus, regardless the connected devices.

Re: Disconnect SCSI from Itanium box without turning off?

Steven E. Protter — Fri, 09 Feb 2007 08:21:15 GMT

Shalom,

We've done it with PA-RISC machine with a 99% success rate.

Its never a good idea to do this while an Oracle database is running on the storage, but beyond that its pretty safe.

Just that 1% of the time that crashes systems that bothers me. Older PA-RISC systems required scsi termination. The lack of termiation caused crashes.

Newer systems and tape drives are self terminating, eliminating the problem.

SEP

Re: Disconnect SCSI from Itanium box without turning off?

Torsten. — Fri, 09 Feb 2007 08:56:25 GMT

On newer systems the internal and external busses are seperated. The older systems are using only one bus for internal devices and provide a connector for external. If you disconnect the external devices, the internal was open. this is the reason.

Anyway, don't open an active bus!
(valid for every SCSI bus).

Re: Disconnect SCSI from Itanium box without turning off?

Kalin Evtimov — Mon, 12 Feb 2007 03:45:50 GMT

Thank you for this information!