7.5.11 Dealing with the server that does not release the reservation (using SCSI reservation for shared disk)

If any of the following events occurs, the reservation has not been released:

A host failure occurred on the active system while hot standby was not possible, such as when the standby server was inactive
The OS was shut down while the active server was running
The KAMN728-W message is output while stopping a server that has experienced system-switching after a host failure

The reservation must be released manually before the server is restarted. If the server is restarted without releasing the reservation, the KAMN725-W message is output and the server startup fails.

The following steps show the procedure for releasing the reservation manually:

Make sure that the failed active server is stopped.

If it is not stopped, stop the server, shut down the OS, or turn off the power of the machine.
See 7.5.12 Canceling SCSI reservation for shared disk, and release the reservation.

You do not have to make the comparison with the keys that are output in the KAMN725-W message in step 1.

For keys and device names specified for each step, do not specify the values output in the KAMN725-W message. Instead, specify the following values:
- Key: 0xn of Key=0xn that is output as the execution result in step 1.
  
  Steps after step 2 do not have to be executed for device names for which PR generation=0xnn, there is NO reservation held is output as an execution result in step 1.
- Device name: scsi_device operand and dmmp_device operand specified value of the environment setting for servers
  
  If multiple device names are specified to each operand, steps from 1 to 4 are executed for each specified value.

The following shows an example of a shell that uses the sg_persist command to release reservations.

The following reservations are released:

/dev/disk/by-id/scsi-360060e8010462fe004f2b6ae00000001
/dev/disk/by-id/scsi-360060e8010462fe004f2b6ae00000002

/dev/disk/by-id/scsi-360060e8010462fe004f2b6ae00000003

#!/bin/sh
 
DEV_LIST="/dev/disk/by-id/scsi-360060e8010462fe004f2b6ae00000001 /dev/disk/by-id/scsi-360060e8010462fe004f2b6ae00000002 /dev/disk/by-id/scsi-360060e8010462fe004f2b6ae00000003"
KEY="0x01"
 
for DESTDEV in ${DEV_LIST}
do
  echo "It processes ${DESTDEV} device."
  echo "execute register."
  /usr/bin/sg_persist --out --no-inquiry --register --param-sark=${KEY} --device=${DESTDEV}
 
  echo "execute clear."
  /usr/bin/sg_persist --out --no-inquiry --clear --param-rk=${KEY} --device=${DESTDEV}
 
  echo "execute read-reservation."
  /usr/bin/sg_persist --in --no-inquiry --read-reservation --device=${DESTDEV}
 
  echo "execute read-keys."
  /usr/bin/sg_persist --in --no-inquiry --read-keys --device=${DESTDEV}
  echo ""
done
 
exit 0

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