Cache Backup Device in Write-Protect Mode
The causes and resolutions refer to the Dell Modular Disk Storage Manager recovery guru. Launch Dell Modular Disk Storage Manager to diagnose and fix the recovery failure as follows:
Open Start >> Programs >> Dell >> MD Storage Manager >> Modular Disk Storage Manager Client.
If the MD Storage Array is already being managed by MDSM, you can proceed with the Causes and Resolution sections.
From Edit -> Add Storage Array, provide the IP address of the MD Storage Array and Add it to the discovered devices configuration in order to manage it.
Select the MD Storage Array and follow the steps specified in this recovery guru.
A cache backup device is currently in write-protect (read-only) mode. 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
While in write-protect mode, cached data cannot be written to the backup device.
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 cache backup device in write-protect mode. The writable cache backup device capacity is now less than the amount of the RAID controller module'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 in Write-Protect Mode) first.
Write caching for all virtual disks has been automatically suspended. Write caching will be reinstated after the RAID controller module has been replaced.
The RAID controller module servicing procedure varies depending on whether your storage array has one or two controllers modules. Consult the appropriate hardware manual if you need details on locating and replacing the controllers modules.
To ensure a complete configuration restore (both disk pool and traditional disk 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[0] contentType=all file="hostfile.zip";
If... | Then... |
Your storage array has one RAID controller module | Go to 'Procedure for Storage Arrays with One RAID Controller Module'. |
Your storage array has two RAID controller modules | Go to 'Procedure for Storage Arrays with Two RAID Controller Modules'. |
Procedure for Storage Arrays with One RAID Controller Module
1 | Stop all I/O from all hosts to this storage array. When the Cache Active LED on the RAID controller module 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 | Click the Save As button in the Recovery Guru dialog to save the remaining steps to file. The remaining Recovery Steps will no longer be accessible from the Recovery Guru dialog after you complete step 3. | ||||||
3 | Remove the RAID controller module canister that contains the affected cache backup device (identified in the Details area). | ||||||
4 | Refer to the Enterprise Management Window (EMW) to view which management method you are using to manage this storage array.
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5 | If the new RAID controller module module does NOT contain a battery, insert the battery from the old RAID controller module canister into the new replacement RAID controller module canister. Consult your hardware documentation for details. | ||||||
6 | Insert the RAID controller module canister securely into place. After the RAID controller module appears on the Hardware tab in the Array Management Window, go to step 7. Note: Write caching will be reinstated (if applicable for each virtual disk) once the RAID controller module's battery is fully charged and has completed any required learn cycles (if applicable). | ||||||
7 | Click the Recheck button to rerun the Recovery Guru. The failure should no longer appear in the Summary area. If the failure appears again, contact your Technical Support Representative. |
Procedure for Storage Arrays with Two RAID Controller Modules
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 RAID controller module offline.
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3 | Read all of the following steps before taking any action. The remaining recovery steps will no longer be accessible from the Recovery Guru dialog after you complete step a.
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| Target | Microsoft.SystemCenter.ManagementServer | ||
| Category | Alert | ||
| Enabled | True | ||
| Alert Generate | True | ||
| Alert Severity | Warning | ||
| Alert Priority | Normal | ||
| Remotable | True | ||
| Alert Message |
|
| ID | Module Type | TypeId | RunAs |
|---|---|---|---|
| DS | DataSource | Microsoft.Windows.ScriptGenerated.EventProvider | Default |
| Alert | WriteAction | System.Health.GenerateAlert | Default |
| WriteToDW | WriteAction | Microsoft.SystemCenter.DataWarehouse.PublishEventData | Default |
Home
<Rule ID="Dell.MDStorageArray.ABBXMLEvent252" Enabled="onEssentialMonitoring" Target="SystemCenter!Microsoft.SystemCenter.ManagementServer" ConfirmDelivery="true" Remotable="true" Priority="Normal" DiscardLevel="100">
<Category>Alert</Category>
<DataSources>
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<EventNumber>252</EventNumber>
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<SuppressionValue>$Data/PublisherName$</SuppressionValue>
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<Custom1/>
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<WriteAction ID="WriteToDW" TypeID="SCDW!Microsoft.SystemCenter.DataWarehouse.PublishEventData"/>
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