[Linux-cluster] SCSI buffer underrun in logs

[sun sadm]

Hi colleague

Jul 26 23:49:19 redbull04 kernel: scsi(2:0:0) UNDERRUN status detected
0x15-0x800.
Jul 26 23:50:19 redbull04 kernel: scsi(2:0:0) UNDERRUN status detected
0x15-0x800.
Jul 26 23:51:19 redbull04 kernel: scsi(2:0:0) UNDERRUN status detected
0x15-0x800.
Jul 26 23:52:19 redbull04 kernel: scsi(2:0:0) UNDERRUN status detected
0x15-0x800.
Jul 26 23:53:19 redbull04 kernel: scsi(2:0:0) UNDERRUN status detected
0x15-0x800.
Jul 26 23:54:19 redbull04 kernel: scsi(2:0:0) UNDERRUN status detected
0x15-0x800.

This event log appears on both cluster nodes (high availability
cluster) every minute without stopping.
How to find out which fdisk logical name maps to SCSI 2:0:0?
How to troubleshoot and solve this issue? Shoud I fill out a Bugzilla
entry at Red Hat? What is the risk about this issue?

My definition of a SCSI buffer underrun:
A buffer underrun error happens when the flow of data from memory to
SAN device is interrupted long enough for the San buffer to be
emptied,
and writing is halted.

The Oracle Database data seems to be fine.

We use QLA2312 HBA and IBM TotalStorage DS4500 (multipathing is done by RDAC)
We use the kernel module included in RHEL4 Update 3.

Nico