Avago Technologies Syncro CS 9271-8i - Manual (Page 58)

LSI Corporation
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Syncro CS 9271-8i Solution User Guide
October 2013 Chapter 4: System Administration
Understanding Failover Operations
The following figure shows the condition of the two server nodes after the failover.
Figure 39 After Failover from Server A to Server B
After failover, the cluster status is as follows, in terms of managing the drive group and the VDs:
 All shared VDs in A-DG0 have failed over and are now managed by Server B.
 VD3 in B-DG0 is still managed by Server B.
 The CacheCade VD (CC-VD) in A-CC now appears as a foreign VD on Server B but does not service any VDs in
A-DG0 or B-DG0.
After failover, the operating system perspective is as follows:
 The operating system on Server B manages all shared VDs and any exclusive Server B VDs.
After failover, the operating system perspective of I/O transactions is as follows:
 Failover Cluster Manager has moved the I/O transactions for VD2 on A-DG0 to Server B.
 Server B continues to run I/O transactions on B-DG0:VD3.
 I/O transactions that rely on the exclusive A-DG0:VD1 on Server A fail because exclusive volumes do not move
with a failover
NOTE When Server A returns, the management and I/O paths of the pre-
failover configurations are automatically restored.
The following sections provide more detailed information about planned failover and unplanned failover.