A cache backup
device has failed.
What Caused the Problem?
A cache backup device has failed and you will need to replace it. The Recovery Guru Details area provides specific information you will need as you follow the recovery steps.
Caution: Electrostatic charges can damage sensitive components. Always use proper antistatic protection when handling components. Touching components without using a proper ground may damage the equipment.
Important Notes
The purpose of a cache backup device is to preserve cached data in the event of a power failure. Therefore, you should resolve this problem as soon as possible.
If there is also an "Insufficient Cache Backup Device Capacity" problem displayed in the Recovery Guru Summary area, read the following additional important notes:
The "Insufficient Cache Backup Device Capacity" problem is most likely a direct result of the failed cache backup device. The cache backup device capacity is now less than the amount of the controller's cache, and therefore, cannot back up the cached data in the event of a power failure.
Complete the recovery steps for this problem (Cache Backup Device Failed) first. Replacing the failed cache backup device with an appropriate replacement should give the controller enough cache backup capacity, thus resolving the insufficient capacity issue as well.
Write caching for all volumes has been automatically suspended .Write caching will be reinstated (if applicable for each volume) once you replace the failed cache backup device and the total capacity of the cache backup devices becomes equal to or greater than the controllers cache.
The cache backup device servicing procedure varies depending on whether your storage array has one or two controllers. Consult the appropriate hardware manual if you need details on locating and replacing the cache backup devices.
To ensure a complete configuration restore (both disk pool and traditional volume group), it is highly recommended that storage array configuration data is backed up prior to executing this procedure. This is especially important for simplex storage arrays, and controllers that operate without the use of batteries. To save your configuration, open either the Command Line Interface (CLI), or the Script Editor from the Enterprise Management Window (EMW), and execute the following command:
save storageArray dbmDatabase sourceLocation=onboard controller[a] contentType=all file="hostfile.zip";
Recovery Steps
Important: Replacing a cache backup device is considered an advanced recovery procedure. It requires you to remove and open the affected controller canister and replace the failed cache backup device. It is recommended that the procedure is performed by an on-site technician, or under the guidance of a Technical Support Representative.
If... | Then... |
Your storage array has one controller | Go to Procedure for Storage Arrays with One Controller . |
Your storage array has two controllers | Go to Procedure for Storage Arrays with Two Controllers . |
Procedure for Storage Arrays with One Controller
1 | Stop all I/O from all hosts to this storage array. When the Cache Active LED on the controller is no longer blinking (may take several minutes), proceed to step 2. Caution: Risk of Data Loss. You must wait for the Cache Active LED to stop blinking to ensure that all cache has been written to disk. |
2 | Determine the appropriate capacity for the replacement cache backup device by viewing the Hardware > Trays tab in the Storage Array Profile or by clicking the View Tray Components link on the Hardware tab in the Array Management Window (AMW). Ensure you have a replacement device that is the same in capacity as the failed device. |
3 | Click the Save As button in the Recovery Guru dialog to save the remaining steps to a file on your local workstation. The remaining recovery steps will no longer be accessible from the Recovery Guru dialog after you complete step 4. |
4 | Remove the controller canister that contains the affected cache backup device (identified in the Recovery Guru Details area). |
5 | Remove the failed cache backup device (identified in the Recovery Guru Details area) from the controller canister. |
6 | Insert an appropriate replacement cache backup device that is the same capacity as the one that failed. |
7 | Insert the controller canister securely into place. After the controller appears on the Hardware tab in the AMW, go to step 8. Note: Write caching will be reinstated (if applicable for each volume) once the controller's battery is fully charged and has completed any required learn cycles (if applicable). |
8 | Click the Recheck button to rerun the Recovery Guru. The failure should no longer appear in the Recovery Guru Summary area. If the failure appears again, contact your Technical Support Representative. |
Procedure for Storage Arrays with Two Controllers
1 | If there are any hosts connected to this storage array that are NOT running a host-based, multi-path failover driver, stop I/O to the storage array from each of these hosts. | ||||||
2 | Place the affected controller offline.
| ||||||
3 | Determine the appropriate capacity for the replacement cache backup device by viewing the Hardware > Trays tab in the Storage Array Profile or by clicking the View Tray Components link on the Hardware tab in the Array Management Window (AMW). Ensure you have a replacement device that is the same in capacity as the failed device. | ||||||
4 | Click the Save As button in the Recovery Guru dialog to save the remaining steps to a file on your local workstation. The remaining recovery steps will no longer be accessible from the Recovery Guru dialog after you complete step 5. | ||||||
5 | Click the Recheck button to rerun the Recovery Guru. There should be an "Offline Controller" problem reported in the Recovery Guru Summary area. | ||||||
6 | Follow the "Offline Controller" recovery steps until you have removed the controller. After you have removed the controller, do not continue with the "Offline Controller" recovery steps until you are instructed to do so in this procedure. | ||||||
7 | Remove the failed cache backup device (identified in the Details area) from the controller canister. | ||||||
8 | Insert an appropriate replacement cache backup device that is the same capacity as the one that failed. | ||||||
9 | Complete the remaining "Offline Controller" recovery steps. Note: Write caching will be reinstated (if applicable for each volume) once the controller's battery is fully charged and has completed any required learn cycles (if applicable). |
| Target | NetAppESeries.StorageArray | ||
| Parent Monitor | NetAppESeries.StorageArrayAvailability | ||
| Category | Custom | ||
| Enabled | True | ||
| Alert Generate | True | ||
| Alert Severity | Error | ||
| Alert Priority | Normal | ||
| Alert Auto Resolve | True | ||
| Monitor Type | NetAppESeries.FailureUnitMonitorType | ||
| Remotable | True | ||
| Accessibility | Internal | ||
| Alert Message |
| ||
| RunAs | Default | ||
| Comment | Machine generated entity |
Home
<UnitMonitor ID="NetAppESeries.FailureID_0251_Monitor" Accessibility="Internal" Enabled="true" Target="NetAppESeries.StorageArray" ParentMonitorID="NetAppESeries.StorageArrayAvailability" Remotable="true" Priority="Normal" TypeID="NetAppESeries.FailureUnitMonitorType" ConfirmDelivery="true" Comment="Machine generated entity">
<Category>Custom</Category>
<AlertSettings AlertMessage="NetAppESeries.REC_CACHE_BACKUP_DEVICE_FAILED_AlertMessageResourceID">
<AlertOnState>Error</AlertOnState>
<AutoResolve>true</AutoResolve>
<AlertPriority>Normal</AlertPriority>
<AlertSeverity>Error</AlertSeverity>
<AlertParameters>
<AlertParameter1>$Data/Context/Property[@Name='FailureDescription']$</AlertParameter1>
</AlertParameters>
</AlertSettings>
<OperationalStates>
<OperationalState ID="NetAppESeries.StateIdC541BB420958181F52D802659E424720" MonitorTypeStateID="NoIssue" HealthState="Success"/>
<OperationalState ID="NetAppESeries.StateIdE833114FCF6BC9FE2350B2B3EA74B3D8" MonitorTypeStateID="IssueFound" HealthState="Error"/>
</OperationalStates>
<Configuration>
<FailureID>251</FailureID>
<IntervalSeconds>59</IntervalSeconds>
<TimeoutSeconds>300</TimeoutSeconds>
<Trace>0</Trace>
</Configuration>
</UnitMonitor>