HP XP P9500 Storage - Manual (Page 303)

• If you execute the sync command on the file system that is mounted by
ext3/ReiserFS, the following message is output to syslog, but there is no
problem with HDLM operations.
JBD: barrier-based sync failed on sddlmaa1 - disabling barriers
• Before you update the OS SP, uninstall HDLM. After you have updated the
OS SP, re-install HDLM.
For details on HDLM installation and uninstallation, see
Installing HDLM on
page 3-75 and Uninstalling HDLM on page 3-216 .
• If the number of I/O operations that have occurred in the system exceeds
the execution performance of the system (in an environment in which all
of the conditions below exist), the KAPL05008-E message and the call
trace of a kernel might be output.
¢
Hitachi WMS exists in HDLM management-target devices.
¢
In the utility for setting HDLM driver option (dlmsetopt), the number
of retries for allocating memory is set to 0 through 2,147,483,646.
In this case, the system might become unstable, and an error might occur
in the I/O that is being executed. In the dlmsetopt utility, set -1 or a
value greater than the current value for the number of retries for
allocating memory, and then restart the system. If a call trace is output
even after the retry count is set to -1, consider adding memory and
stopping unnecessary processes.
• When a device is dynamically configured by using the udev function, the
messages shown below might be output to the console or syslog.
However, HDLM operations are not affected.
Output example:
scsi_id[a01]: scsi_id: unable to access parent device of '/block/
sddlma01'
For a01 in the above examples, any alphanumeric character can be
output.
Notes When Using SUSE LINUX Enterprise Server 11
Note the following when your OS is SUSE LINUX Enterprise Server 11:
• Before you update the kernel package, uninstall HDLM. After you have
updated the kernel package, re-install HDLM.
For details on HDLM installation and uninstallation, see
Installing HDLM on
page 3-75 and Uninstalling HDLM on page 3-216 .
• SCSI devices corresponding to an HDLM device can be removed
dynamically even while the HDLM device is in use. Before doing so,
perform the following operations:
a
.
Unmount any devices mounted on the HDLM device.
b
.
Execute the dlmcfgmgr -o command to exclude the HDLM device
from management.
HDLM Operation
4-7
Hitachi Dynamic Link Manager User Guide (for Linux(R))