On Fri, Jul 27, 2012 at 07:35:19AM +1000, matthew green wrote: > > > I have a (mpt) SAS with seven discs connected. > > The discs attach as sd0..sd6, but the SCSI target numbers are 0..5 and 7. > > It appears to me that someone is skippig ID 6 for the controller. > > It doesn't hurt too much, but it took me a while to find out why detaching > > targets 2, 3, 4 and 5 worked and 6 didn't (of course, 7 worked). > > > > Is there a reason for this behaviour? > > it's usual for the SCSI HBA to assign a targetID for itself. > > besides having to use a different number, is there any real reason > you want to change them? perhaps a better solution would be to > patch scsictl such that we can detach via autoconf name as well > as scsi addresses. maybe we should do this anyway..
Depending on LSI firmware (I think), the LSI may re-number disks depending on how they present themselves, uuid, etc. Some people like this persistence (mainly Winders users, I imagine), it causes problems for others. To get around this, at work I used lsiutil to clear the NVRAM settings. Otherwise, switching out all the LSI-attached disks in one of the Open Connect Appliances made the drives present themselves as da33 to da64, rather than da1 to da32 - under FreeBSD, obviously. Regards, Alistair