Hitachi Dynamic Link Manager Software Users Guide for Linux

Notes When Using SUSE LINUX Enterprise Server 11
Note the following when your OS is SUSE LINUX Enterprise Server 11:
• To update a kernel package or apply an OS update package, remove
HDLM first. Perform the update and then install HDLM again.
For detailed procedures, see Updating Kernel Packages and Applying OS
Update Packages on page 4-8.
• 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 devices cannot be used to create an md device.
• 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
• 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 series 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.
• Sometimes a hyphen is displayed for the SCSI device name in the Device
column of the results of the dlmcfgmgr utility (dlmcfgmgr -v) or the view
operation of the HDLM command (with either the -lu or -drv parameter
specified). This might happen if one of the problems listed below occurs
while the system is running, even if the SCSI devices are not erased. This
problem is related to the OS's hot-plug function. HDLM operations are not
affected:
¢
A path gets disconnected.
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An LU is deleted.
¢
A fiber cable connection is changed.
¢
A Fibre Channel switch's zone setting is changed.
HDLM Operation
4-7
Hitachi Dynamic Link Manager (for Linux®) User Guide