対称型デバイスでは、使用可能な最適パスへの 自動フェイルバックが可能です。最初のパスでフェイルオーバーが発生した場合、待機パスは新しいオンラインパスになります。通常、待機パスは準最適なパスです。自動フェイルバックが有効な場合、最初のパスがオンラインに戻り、最初のパスへのフェイルオーバーが自動的に発生します。
# mpathadm list mpath-support mpath-support: libmpscsi_vhci.so
# mpathadm modify mpath-support -a on libmpscsi_vhci.so
# mpathadm show mpath-support libmpscsi_vhci.so mpath-support: libmpscsi_vhci.so Vendor: Sun Microsystems Driver Name: scsi_vhci Default Load Balance: round-robin Supported Load Balance Types: round-robin logical-block Allows To Activate Target Port Group Access: yes Allows Path Override: no Supported Auto Failback Config: 1 Auto Failback: on Failback Polling Rate (current/max): 0/0 Supported Auto Probing Config: 0 Auto Probing: NA Probing Polling Rate (current/max): NA/NA Supported Devices: Vendor: SUN Product: T300 Revision: Supported Load Balance Types: round-robin Vendor: SUN Product: T4 Revision: Supported Load Balance Types: round-robin . . .
この操作は、次の 2 つのカテゴリのデバイスにのみ適用されます。
マルチパス化サポートによって認識およびサポートされる、専有のフェイルオーバーメカニズムを持つ非対称型デバイス
T10 標準のターゲットポートグループサポート libmpscsi_vhci.so に準拠し、明示的な非対称型 LU アクセスのモードを提供するデバイス
# mpathadm list lu /dev/rdsk/c0t600144F08069703400004E828EE10004d0s2 Total Path Count: 8 Operational Path Count: 8 /dev/rdsk/c0t600144F08069703400004E8183DF0002d0s2 Total Path Count: 8 Operational Path Count: 8 /dev/rdsk/c0t600A0B800026D63A0000A4994E2342D4d0s2 Total Path Count: 4 Operational Path Count: 4 /dev/rdsk/c0t600A0B800029065C00007CF54E234013d0s2 Total Path Count: 4 Operational Path Count: 4 /dev/rdsk/c0t600A0B800026D63A0000A4984E234298d0s2 Total Path Count: 4 Operational Path Count: 4 . . .
# mpathadm show lu /dev/rdsk/c0t600A0B800026D63A0000A4984E234298d0s2 Logical Unit: /dev/rdsk/c0t600A0B800026D63A0000A4984E234298d0s2 mpath-support: libmpscsi_vhci.so Vendor: SUN Product: CSM200_R Revision: 0660 Name Type: unknown type Name: 600a0b800026d63a0000a4984e234298 Asymmetric: yes Current Load Balance: round-robin Logical Unit Group ID: NA Auto Failback: on Auto Probing: NA Paths: Initiator Port Name: 210000e08b841feb Target Port Name: 200800a0b826d63b Override Path: NA Path State: OK Disabled: no Initiator Port Name: 210000e08b841feb Target Port Name: 200900a0b826d63b Override Path: NA Path State: OK Disabled: no Initiator Port Name: 210000e08b841feb Target Port Name: 200800a0b826d63c Override Path: NA Path State: OK Disabled: no Initiator Port Name: 210000e08b841feb Target Port Name: 200900a0b826d63c Override Path: NA Path State: OK Disabled: no Target Port Groups: ID: 5 Explicit Failover: yes Access State: active Target Ports: Name: 200800a0b826d63b Relative ID: 0 Name: 200800a0b826d63c Relative ID: 0 ID: 15 Explicit Failover: yes Access State: standby Target Ports: Name: 200900a0b826d63b Relative ID: 0 Name: 200900a0b826d63c Relative ID: 0
# mpathadm failover lu /dev/rdsk/c0t600A0B800026D63A0000A4984E234298d0s2
この操作に成功した場合、デバイスのターゲットポートグループのアクセス状態は、論理ユニットのフェイルオーバーの結果、変更されます。
# mpathadm show lu /dev/rdsk/c0t600A0B800026D63A0000A4984E234298d0s2 Logical Unit: /dev/rdsk/c0t600A0B800026D63A0000A4984E234298d0s2 mpath-support: libmpscsi_vhci.so Vendor: SUN Product: CSM200_R Revision: 0660 Name Type: unknown type Name: 600a0b800026d63a0000a4984e234298 Asymmetric: yes Current Load Balance: round-robin Logical Unit Group ID: NA Auto Failback: on Auto Probing: NA Paths: Initiator Port Name: 210000e08b841feb Target Port Name: 200800a0b826d63b Override Path: NA Path State: OK Disabled: no Initiator Port Name: 210000e08b841feb Target Port Name: 200900a0b826d63b Override Path: NA Path State: OK Disabled: no Initiator Port Name: 210000e08b841feb Target Port Name: 200800a0b826d63c Override Path: NA Path State: OK Disabled: no Initiator Port Name: 210000e08b841feb Target Port Name: 200900a0b826d63c Override Path: NA Path State: OK Disabled: no Target Port Groups: ID: 5 Explicit Failover: yes Access State: standby Target Ports: Name: 200800a0b826d63b Relative ID: 0 Name: 200800a0b826d63c Relative ID: 0 ID: 15 Explicit Failover: yes Access State: active Target Ports: Name: 200900a0b826d63b Relative ID: 0 Name: 200900a0b826d63c Relative ID: 0
LU へのパスが無効な場合、enable コマンドによってパスは元の有効な状態に変更されます。イニシエータポート名、ターゲットポート名、および LU を使用して、完全なパス名を指定する必要があります。変更を確認するには、論理ユニットに対して show コマンドを実行します。
# mpathadm list lu /dev/rdsk/c0t600144F08069703400004E828EE10004d0s2 Total Path Count: 8 Operational Path Count: 8 /dev/rdsk/c0t600144F08069703400004E8183DF0002d0s2 Total Path Count: 8 Operational Path Count: 8 /dev/rdsk/c0t600A0B800026D63A0000A4994E2342D4d0s2 Total Path Count: 4 Operational Path Count: 4 /dev/rdsk/c0t600A0B800029065C00007CF54E234013d0s2 Total Path Count: 4 Operational Path Count: 4 /dev/rdsk/c0t600A0B800026D63A0000A4984E234298d0s2 Total Path Count: 4 Operational Path Count: 4 /dev/rdsk/c0t600A0B800029065C00007CF44E233FCFd0s2 Total Path Count: 4 Operational Path Count: 4 . . .
# mpathadm show lu Logical Unit: /dev/rdsk/c0t600A0B800026D63A0000A4984E234298d0s2 mpath-support: libmpscsi_vhci.so Vendor: SUN Product: CSM200_R Revision: 0660 Name Type: unknown type Name: 600a0b800026d63a0000a4984e234298 Asymmetric: yes Current Load Balance: round-robin Logical Unit Group ID: NA Auto Failback: on Auto Probing: NA Paths: Initiator Port Name: 210000e08b841feb Target Port Name: 200800a0b826d63b Override Path: NA Path State: OK Disabled: no Initiator Port Name: 210000e08b841feb Target Port Name: 200900a0b826d63b Override Path: NA Path State: OK Disabled: no Initiator Port Name: 210000e08b841feb Target Port Name: 200800a0b826d63c Override Path: NA Path State: OK Disabled: no Initiator Port Name: 210000e08b841feb Target Port Name: 200900a0b826d63c Override Path: NA Path State: OK Disabled: no Target Port Groups: ID: 5 Explicit Failover: yes Access State: standby Target Ports: Name: 200800a0b826d63b Relative ID: 0 Name: 200800a0b826d63c Relative ID: 0 ID: 15 Explicit Failover: yes Access State: active Target Ports: Name: 200900a0b826d63b Relative ID: 0 Name: 200900a0b826d63c Relative ID: 0
# mpathadm enable path -i 210000e08b841feb -t 200900a0b826d63b \ -l /dev/rdsk/c0t600A0B800026D63A0000A4984E234298d0s2
この操作は、その操作状態に関係なく、LU パスを無効にします。
# mpathadm list lu /dev/rdsk/c0t600144F08069703400004E828EE10004d0s2 Total Path Count: 8 Operational Path Count: 8 /dev/rdsk/c0t600144F08069703400004E8183DF0002d0s2 Total Path Count: 8 Operational Path Count: 8 /dev/rdsk/c0t600A0B800026D63A0000A4994E2342D4d0s2 Total Path Count: 4 Operational Path Count: 4 /dev/rdsk/c0t600A0B800029065C00007CF54E234013d0s2 Total Path Count: 4 Operational Path Count: 4 /dev/rdsk/c0t600A0B800026D63A0000A4984E234298d0s2 Total Path Count: 4 Operational Path Count: 4 /dev/rdsk/c0t600A0B800029065C00007CF44E233FCFd0s2 Total Path Count: 4 Operational Path Count: 4 . . .
# mpathadm show lu /dev/rdsk/c0t600A0B800029065C00007CF34E233F89d0s2 Logical Unit: /dev/rdsk/c0t600A0B800029065C00007CF34E233F89d0s2 mpath-support: libmpscsi_vhci.so Vendor: SUN Product: CSM200_R Revision: 0660 Name Type: unknown type Name: 600a0b800029065c00007cf34e233f89 Asymmetric: yes Current Load Balance: round-robin Logical Unit Group ID: NA Auto Failback: on Auto Probing: NA Paths: Initiator Port Name: 210000e08b841feb Target Port Name: 200800a0b826d63b Override Path: NA Path State: OK Disabled: no Initiator Port Name: 210000e08b841feb Target Port Name: 200900a0b826d63b Override Path: NA Path State: OK Disabled: no Initiator Port Name: 210000e08b841feb Target Port Name: 200800a0b826d63c Override Path: NA Path State: OK Disabled: no Initiator Port Name: 210000e08b841feb Target Port Name: 200900a0b826d63c Override Path: NA Path State: OK Disabled: no Target Port Groups: ID: 8 Explicit Failover: yes Access State: standby Target Ports: Name: 200800a0b826d63b Relative ID: 0 Name: 200800a0b826d63c Relative ID: 0 ID: 18 Explicit Failover: yes Access State: active Target Ports: Name: 200900a0b826d63b Relative ID: 0 Name: 200900a0b826d63c Relative ID: 0
# mpathadm disable path -i 210000e08b841feb -t 200900a0b826d63b \ -l /dev/rdsk/c0t600A0B800029065C00007CF34E233F89d0s2