The S2600 controller maps each of the two application servers (ASs) to a LUN, and when both LUNs are activated, the primary node can be started properly but not for the other node when the cluster is being started.
Oct 14 23:25:56 AK-I kernel: Reserve (6) command for Host LUN 0, Device Lun 8 @ [jif=372919227] SCSI_PrintDebugInfo : 1382 ...... Oct 14 23:25:56 AK-I kernel: SCSI_ClearReserveExec Oct 14 23:25:56 AK-I kernel:  @ [jif=372919957] SCSI_ClearReserveExec : 2200 Oct 14 23:25:56 AK-I kernel: This is the master controller Oct 14 23:25:56 AK-I kernel:  @ [jif=372919957] SCSI_ClearReserveExec : 2207 Oct 14 23:25:56 AK-I kernel: Enter SCSI_ClearReserve Oct 14 23:25:56 AK-I kernel:  @ [jif=372919957] SCSI_ClearReserve : 2286
After executing the Reserve command, the initially started primary node doesn't clear the command timely.
If no LUNs are mapped to ASs, when you start the cluster, the initially started primary node executes the Reserve command, and then the LOGOUT command to clear the Reserve command. Later, the other node repeats the same procedure as well. Since the LOGOUT command clears all the existed sessions while the LUNs and shared disks share the same session for the primary node, when one of the LUNs that is private to a node is activated, the primary node doesn't execute the LOGOUT command to clear all the sessions, which results in the startup failure of the other node.
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