[Linux-cluster] RH4U5 and SCSI-3 Persistent reservation

[Maciej Bogucki]

Hello,

I want to run fencing based on SCSI-3 persisten reservation protocol. I
have two servers with GFS filesystem and I want to write to all of them
at one time. But when I start scsi_reserve on the second node I get:

---cut---
Aug 10 11:26:08 host2 scsi_reserve: register of device /dev/sdb1 succeeded
Aug 10 11:26:08 host2 kernel: scsi0 (0,0,1) : reservation conflict
Aug 10 11:26:08 host2 kernel: 492 [RAIDarray.mpp]Array_Module_0:1:0:1 IO
FAILURE. vcmnd SN 35975 pdev H0:C0:T0:L1 0x00/0x00/0x00 0x00000018
mpp_status:3
Aug 10 11:26:08 host2 kernel: scsi2 (0,0,1) : reservation conflict
Aug 10 11:26:08 host2 kernel: SCSI error : <2 0 0 1> return code = 0x18
---cut---

So I think that RH4U5 only supports SCSI-2 persistent reservations.

But here [1] we can read that RH4U5 support for SCSI-3 persistent group
reservations. SCSI-3 is a group reservation: every node has a key on a
dedicated area on the disk and when a node has to leave, another node
will just kick off its key. So it is what I'm looking for.

[1] - http://www.desktoplinux.com/news/NS3524659857.html

Best Regards
Maciej Bogucki