need help to suspend a device

Hi,

I need some help with device suspending or something similar to this.

Problem description: We have many many Infortrend sata-to-scsi-raid systems here, connected to several server systems with LSI2230 HBAs. Now the problem is, that these Infortrend boxes sometimes suffer from some kind of hick-up, sometimes due to the reboot of second server connected to the very same Infortrend box and sometimes just for no obvious reason.

As far I can presently see it, the best would be to suspend any i/o, commands, etc to the troublesome box for about 30s to 60s and just wait and then to repeat the last command.
However, presently the scsi-layer/driver will immediately begin a domain validation and then do a scsi-reset. Unfortunately this will cause even more trouble. Sometimes this works, in more cases it will end in an i/o error and in most cases these domain validations and scsi-resets will go into an endless loop and eventually the Infortrend raids will be so confused that their scsi-controller will crash.

I'm already looking for some hours through the scsi and mpt functions, but so far didn't find a good way to put commands to a scsi-device to sleep for some time.

Any hints and suggestions are highly appreciated.

Thanks in advance,
Bernd

Bernd Schubert
Q-Leap Networks GmbH