HP XP7 Storage - Manual (Page 216)

Notes and restrictions Items
The HORC Manager must not be an object of the process monitoring by the HA software
(cluster manager), because HORCM should run in the same level as the cluster manager. Linkage with HA software
Cooperation with HA software is done by activating the takeover command from the shell
script activated by the cluster manager in units of the package software.
Note: Cannot use a pair volume for the cluster lock disk that HA software uses for election.
Restart of HORCM is required if the storage system configuration is changed (for example,
microcode exchange, cache memory install/uninstall). Maintenance
Continuous Access Synchronous only: In the case of an error (for example, single error in
cache memory) which made the pair volume is accompanied by maintenance work, the
pairresync
or paircreate command cannot execute copy rejection.
Each Continuous Access Synchronous/Business Copy command is executed by issuing a
command to the command device. The Continuous Access Synchronous/Business Copy Command device
command is read or written from/into the specific block area of the command device.
Therefore, the command device cannot be used. In addition, this device must not belong
to an LVM volume group. For Windows systems, do not assign a drive letter to the command
device to prevent utilization by general users.
If the P-VOL and S-VOL are on the same server, alternate path from P-VOL to S-VOL cannot
be used. Use of SCSI alternate path to a volume pair in the pair status is limited to among SCSI alternate path
restrictions
primary (secondary) volumes. Alternate path using Path Manager (Safe Path) is limited to
primary volumes.
When executing horctakeover on a standby server manually, I/O on the active server
must be stopped. When the package software goes for a standby server a failover by HA
software, the HA software must guarantee an I/O insulation of the active server. horctakeover
(Swap-Takeover)
After a new system has been constructed, a failure to activate HORCM may occur due to
improper environment setting and/or configuration definition. Refer to the HORCM activation
log, and correct the settings. HORCM failure to activate
Refer to the command log file and HORCM log file to identify the cause of the error. If a
command terminates abnormally because of a remote server failure, recover the server Abnormal termination of
command
from the failure, then re-execute the command. If HORCM has shut down, restart HORCM.
If an unrecoverable error occurs, obtain the log files and contact the HP Technical Support.
Continuous Access Synchronous only: If an error occurs in duplicated writing in paired
volumes (that is, pair suspension), the server software using the volumes may detect the Error in paired volume
operation
error by means of the fence level of the paired volume. In such a case, check the error
notification command or syslog file to identify a failed paired volume.
The system administrator can confirm that duplicated writing in a paired volume is suspended
due to a failure and the system runs in regressed state using the error notification command
of the Continuous Access Synchronous. HORCM monitors failures in paired volumes at
regular intervals. When it detects a failure, it outputs it to the host's syslog file. Thus, the
system administrator can detect the failure by checking the syslog file. Concerning the
operation of the RAID storage system, the failure can also be found on Remote Web Console
(or SVP) provided.
216 Troubleshooting