Chapter 11: Maintaining a Storage Array
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Taking a controller offline can seriously impact data integrity and storage array
operation.
If you do not use write cache mirroring, data in the cache of the controller you
place offline is lost.
If you take a controller offline and you have controller failover protection through
a host multi-path driver, the other controller in the pair takes over. Volume groups
and their associated volumes that were assigned to the offline controller are
automatically reassigned to the remaining controller. If you do not have a
multi-path driver installed on the application host and you take a controller
offline while the application is using associated volumes, application errors will
occur.
ATTENTION Possible loss of data access
– Placing a controller offline can cause
loss of data.
Use Service mode to replace canisters, such as a controller. Placing a controller in
Service mode makes it unavailable for I/O operations and moves its volume groups to
the second controller without affecting the preferred path of the volume group. This
action might significantly reduce performance. The volume groups are automatically
transferred back to the preferred controller when it is placed back online.
If you change a controller to Service mode while an application is using the
associated volumes on the controller, the change causes I/O errors unless a multi-path
driver is installed on the host. Before you place a controller in Service mode, make
sure that the volumes are not in use, or a multi-path driver is installed on all of the
hosts that are using these volumes.
In addition, if you do not have a multi-path driver, you must make appropriate
operating system-specific modifications to make sure that the volume groups moved
are accessed on the new path when you change to Service mode.
NOTE
Place a controller in Service mode only under the direction of a Technical
Support representative.
To change the operational mode of a controller, use this command:
set controller [(a | b)] availability=(online |
offline | serviceMode)
Summary of Contents for InfiniteStorage 4000 Series
Page 34: ...22 ExitStatus ...
Page 48: ...36 Adding Comments to a Script File ...
Page 110: ...98 Starting Stopping and Resuming a Snapshot Legacy Rollback ...
Page 168: ...156 Interaction with Other Premium Features ...
Page 182: ...170 Interaction with Other Premium Features ...
Page 192: ...180 SSD Cache Management Tasks ...
Page 216: ...204 RecoveryOperations ...
Page 218: ...206 Show Storage Array ...
Page 219: ...Appendix A Examples of Information Returned by the Show Commands 207 ...
Page 220: ...208 Show Storage Array ...
Page 221: ...Appendix A Examples of Information Returned by the Show Commands 209 ...
Page 222: ...210 Show Storage Array ...
Page 223: ...Appendix A Examples of Information Returned by the Show Commands 211 ...
Page 224: ...212 Show Storage Array ...
Page 225: ...Appendix A Examples of Information Returned by the Show Commands 213 ...
Page 226: ...214 Show Storage Array ...
Page 227: ...Appendix A Examples of Information Returned by the Show Commands 215 ...
Page 228: ...216 Show Storage Array ...
Page 229: ...Appendix A Examples of Information Returned by the Show Commands 217 ...
Page 230: ...218 Show Storage Array ...
Page 231: ...Appendix A Examples of Information Returned by the Show Commands 219 ...
Page 233: ...Appendix A Examples of Information Returned by the Show Commands 221 ...
Page 234: ...222 Show Controller NVSRAM ...
Page 253: ...Appendix A Examples of Information Returned by the Show Commands 241 ...
Page 254: ...242 ShowDrive ...
Page 255: ...Appendix A Examples of Information Returned by the Show Commands 243 ...
Page 256: ...244 ShowDrive ...
Page 257: ...Appendix A Examples of Information Returned by the Show Commands 245 ...
Page 258: ...246 ShowDrive ...
Page 268: ...256 ConfigurationUtility ...
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Page 276: ...Copyright 2012 NetApp Inc All rights reserved ...