AIX and Linux Utility for Clearing HDLM Persistent Reservation
Utility for Clearing HDLM Persistent Reservation
Format
Linux:
Format
/opt/DynamicLinkManager/bin/dlmpr {{-k | -c} [sdn] [sdn] ... [-a] | -h}
Parameters
Specify this parameter to display the reservation key. The following
explains the items displayed when the -k parameter is specified:
Reservation Key
If the reservation key is not set, [0x0000000000000000] is displayed.
Parameters
Register Key
The registered keys are displayed.
Key Count
The number of registered keys is displayed.
-c
Specify this parameter to clear the reservation key.
sdn
Specify the SCSI device (sdn) for which you want to display or clear the
reservation key. You can specify more than one SCSI device.
If you omit this parameter, the utility displays or clears the reservation
keys for all SCSI devices.
-a
Even if an error occurs during processing, processing continues for all
remaining SCSI devices.
-h
Displays the format of the utility for clearing HDLM persistent reservation.
Example
To check the reservation keys, and then clear a reservation key:
1. Execute the dlmpr utility to display the reservation keys for sda, sdb,
sdc, sdd, sde, and sdf.
# /opt/DynamicLinkManager/bin/dlmpr -k sda sdb sdc sdd sde sdf
sda Reservation Key : [0xaaaaaaaaaaaaaaaa]
Regist Key : [0xaaaaaaaaaaaaaaaa], Key Count : 1
sdb Reservation Key : [0xbbbbbbbbbbbbbbbb]
Regist Key : [0xaaaaaaaaaaaaaaaa], Key Count : 2
Regist Key : [0xbbbbbbbbbbbbbbbb], Key Count : 2
Regist Key : [0xbbbbbbbbbbbbbbbb], Key Count : 1
2. Execute the dlmpr utility to clear the reservation key.
# /opt/DynamicLinkManager/bin/dlmpr -c sdb sdc
3. The confirmation message appears. Enter y to clear. Otherwise, enter n.
KAPL10641-I Reservation Key will now be cleared. Is this OK?
[y/n]:y
KAPL10642-I Reservation Key of sdb was cleared.
AIX:
/usr/DynamicLinkManager/bin/dlmpr {{-k | -c} [hdiskn] [hdiskn]... [-a] | -h}
-k
Specify this parameter to display the Reservation Key. The following explains the items displayed when the -k parameter is specified:
Reservation Key
An asterisk (*) is displayed at the end of the Reservation Key for a Reservation Key of another host. If the Reservation Key is not set, [0x0000000000000000] is displayed.
Regist Key
The registered Keys are displayed.
Key Count
The number of registered Keys is displayed.
-c
Specify this parameter to clear the Reservation Key.
hdiskn
Specify the physical volume (hdiskn) for which you want to display or clear the Reservation Key. You can specify more than one volume. If you omit this parameter, the utility assumes all the physical volumes.
-a
When multiple physical volumes (hdiskn) are specified, even if an error occurs during processing, the processing continues for all physical volumes.
-h
Displays the format of the utility for clearing HDLM persistent reservation.
Notes
[0x????????????????] appears for Reservation Key if the destination storage subsystem does not support the persistent reservation or if a hardware error occurs.
Also take note that this utility can be executed in the AIX server where HDLM is installed and running.
To prevent reservation conflicts, use the DLMCHPDATTR command to set the ODM default reserve policy to no_reserve
HDLM:
Execute the dlmchpdattr utility with the -A parameter specified.
# /usr/DynamicLinkManager/bin/dlmchpdattr -A -a reserve_policy=no_reserve
A message is displayed that asks you to confirm that processing should
continue. Enter y to continue processing.
Notes
• Before you execute the dlmchpdattr utility, stop all application processes
that access HDLM-managed devices.
• Before you execute the dlmchpdattr utility, make sure that no path
errors are occurring. If there are any errors, the dlmchpdattr utility
might end with an error.
• If you cancel the execution of the dlmchpdattr utility by pressing Ctrl +
C, the KAPL10571-I message might be output depending on the timing of
the cancellation. This message signifies that the setting change was not
successful. If this message is output, re-execute the dlmchpdattr utility
with the same parameters specified. To return the settings to their
previous state, make sure that the above setting change was successful,
and then execute the dlmchpdattr utility with the original parameters
specified.
Examples
In the following example, the utility changes the default hdisk reservation
policy to no_reserve:
# /usr/DynamicLinkManager/bin/dlmchpdattr -a
reserve_policy=no_reserve
KAPL10579-I The HDLM default values will be changed. Is this OK?
[y/n]:y
KAPL10571-I The dlmchpdattr utility completed successfully.
In the following example, the utility changes the default hdisk reservation
policy to no_reserve, as well as changing the default number of requests
that the queue on the disk can hold to 4:
# /usr/DynamicLinkManager/bin/dlmchpdattr -a
"reserve_policy=no_reserve queue_depth=4"
KAPL10579-I The HDLM default values will be changed. Is this OK?
[y/n]:y
KAPL10571-I The dlmchpdattr utility completed successfully.