Dell PowerEdge RAID Controller 6E - Manual (Page 127)

Troubleshooting
127
Linux Operating System Errors
Table 7-8 describes issues related to the Linux operating system.
Table 7-8. Linux Operating System Errors
Error Message Suggested Solution
kernel: sdb: asking for
cache data failed
kernel: sdb: assuming
drive cache: write
through
This error message displays when the Linux
Small Computer System Interface (SCSI)
mid-layer asks for physical disk cache settings.
The controller firmware manages the virtual disk
cache settings on a per controller and a per
virtual disk basis, so the firmware does not
respond to this command. The Linux SCSI mid-
layer assumes that the virtual disk's cache policy
is Write-Through. SDB is the device node for a
virtual disk. This value changes for each virtual
disk.
See the section "Physical Disk Management" on
page 105 for more information about Write-
Through cache.
Except for this message, there is no effect of this
behavior on normal operation. The cache policy
of the virtual disk and the I/O throughput are
not affected by this message. The cache policy
settings for the PERC6 SAS RAID system
remain unchanged.
Dell_PERC6.2_UG.book Page 127 Wednesday, June 24, 2009 6:08 PM