To Fail Over a Logical Unit

This operation is applicable only to devices in the following two categories:

• Asymmetric devices with a proprietary failover mechanism recognized and supported by multipathing support

• Devices conforming to the T10 Standard Target Port Group Support libmpscsi_vhci.so and providing explicit mode asymmetric logical unit access

1. Run the mpathadm list lu command.

   # mpathadm list lu /dev/rdsk/c4t60020F20000035AF4267CCCB0002CEE2d0s2 Total Path Count: 2 Operational Path Count: 2 /dev/rdsk/c4t60003BA27D2120004204AC2B000DAB00d0s2 Total Path Count: 2 Operational Path Count: 2 /dev/rdsk/c4t60003BA27D2120004204AC1A000F1D6Cd0s2 Total Path Count: 2 Operational Path Count: 2

2. Select a logical unit name from the output.

3. Run the mpathadm show lu logical-unit-name command.

   # mpathadm show lu /dev/rdsk/c4t60003BA27D2120004204AC2B000DAB00d0s2 logical unit: /dev/rdsk/c4t60003BA27D2120004204AC2B000DAB00d0s2 mpath-support libmpscsi_vhci.so Vendor: SUN Product: T4 Revision: 0301 Name Type: SCSI Inquiry VPD page 83 type 3 Name: 60003ba27d2120004204ac2b000dab00 Asymmetric: yes Current Load Balance: round-robin Logical Unit Group ID: NA Auto Failback: on Auto Probing: NA Paths: Initiator Port Name: 2000000173818713 Target Port Name: 20030003ba27d212 Override Path: NA Path State: OK Disabled: no Initiator Port Name: 2000000173018713 Target Port Name: 20030003ba27d095 Override path: NA Path State: OK Disabled: no Target Port Groups: ID: 2 Explicit Failover: yes Access State: standby Target Ports: Name: 20030003ba27d212 Relative ID: 0 ID: 5 Explicit Failover: yes Access State: active Target Ports: Name: 20030003ba27d095 Relative ID: 0

4. Run the mpathadm failover lu logical-unit-name command.

   # mpathadm failover lu /dev/rdsk/c4t60003BA27D2120004204AC2B000DAB00d0s2

   If this operation is successful, the access state of the devices’ target port groups changes as a result of the logical unit failover.

5. Run the mpathadm show lu logical-unit-name command to verify the access state change.

   # mpathadm show lu /dev/rdsk/c4t60003BA27D2120004204AC2B000DAB00d0s2 logical unit: /dev/rdsk/c4t60003BA27D2120004204AC2B000DAB00d0s2 mpath-support libmpscsi_vhci.so Vendor: SUN Product: T4 Revision: 0301 Name Type: SCSI Inquiry VPD page 83 type 3 Name: 60003ba27d2120004204ac2b000dab00 Asymmetric: yes Current Load Balance: round-robin Logical Unit Group ID: NA Auto Failback: on Auto Probing: NA Paths: Initiator Port Name: 2000000173818713 Target Port Name: 20030003ba27d212 Override Path: NA Path State: OK Disabled: no Initiator Port Name: 2000000173018713 Target Port Name: 20030003ba27d095 Override path: NA Path State: OK Disabled: no Target Port Groups: ID: 2 Explicit Failover: yes Access State: active Target Ports: Name: 20030003ba27d212 Relative ID: 0 ID: 5 Explicit Failover: yes Access State: standby Target Ports: Name: 20030003ba27d095 Relative ID: 0