Planned outages for system components
................................................................................
46
Options for performing the planned outages
.....................................................................
46
The procedures for performing planned outages
................................................................
47
Performing planned outages (quorum disk only)
...............................................................
47
Performing planned outages (primary storage system and quorum disk)
................................
48
Performing planned outages (secondary storage system and quorum disk)
............................
49
Performing planned outages (both storage systems and quorum disk)
...................................
50
6 Disaster recovery
......................................................................................
51
Main types of failures that can disrupt your system
......................................................................
51
The basic recovery process
......................................................................................................
51
System failure messages
..........................................................................................................
51
Detecting failures
....................................................................................................................
51
Option 1: Check for failover first
..........................................................................................
51
Using Remote Web Console to check for failover
...............................................................
52
Using RAID Manager to check for failover
........................................................................
52
Using multipath software to check for failover
....................................................................
52
Option 2: Check for failures only
.........................................................................................
52
Determining which basic recovery procedures to use
...................................................................
53
Selecting Procedures
..........................................................................................................
53
Recovery from blocked pair volumes
.........................................................................................
54
Recovering from primary volume failure on the MCU
..............................................................
54
Recovering from secondary volume failure on the MCU
...........................................................
55
Recovering from primary volume failure on the RCU
...............................................................
56
Recovering from secondary volume failure on the RCU
...........................................................
57
Recovery from quorum disk failure
............................................................................................
57
Replacement of quorum disks
..............................................................................................
57
Replacing a quorum disk when the MCU is receiving host I/O
............................................
57
Replacing a quorum disk when the RCU is receiving host I/O
.............................................
58
Recovery from power failure
.....................................................................................................
59
primary storage system recovery
..........................................................................................
59
Recovering the system when the RCU is receiving host I/O updates
......................................
60
Recovering the system when host I/O updates have stopped
...............................................
60
Secondary system recovery
.................................................................................................
61
Recovering the system when the P-VOL is receiving host updates
..........................................
61
Recovering the system when host updates have stopped
.....................................................
61
Recovery from failures using resynchronization
............................................................................
62
Required conditions
............................................................................................................
62
Determining which resynchronization recovery procedure to use
...............................................
63
Prerequisites
.................................................................................................................
63
Procedure
....................................................................................................................
64
Recovering primary volume from Business Copy secondary volume
...........................................
64
Prerequisites
.................................................................................................................
64
Procedure
....................................................................................................................
64
Recovering secondary volume from Continuous Access Journal primary volume
.........................
64
Prerequisites
.................................................................................................................
64
Procedure
....................................................................................................................
65
Postrequisites
.....................................................................................................................
65
Recovering from path failures
..................................................................................................
65
Allowing host I/O to an out-of-date S-VOL
.................................................................................
66
7 Using ESAM in a cluster system
..................................................................
67
Cluster system architecture
.......................................................................................................
67
Required software
...................................................................................................................
67
Supported cluster software
.......................................................................................................
67
Configuration requirements
.....................................................................................................
68
Contents
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