Troubleshooting Database Issues

Published : September 27, 2005

DPM processes rely on databases created in Microsoft SQL Server:

• The DPM database (DPMDB.mdf) stores DPM settings and configuration information.

• The Report database (ReportServer.mdf) stores reporting information for DPM.

In addition, DPM processes rely on the following databases: Tempdb.mdf, Master.mdf, Model.mdf, and Msdb.mdf.

Database failures can cause DPM jobs to fail, interfere with the use of DPM Administrator Console, prevent DPM reporting, and cause the DPM service to stop. A backlog of requests caused by low memory or high CPU usage can also cause client time-outs (when DPM processes take a long time to establish a SQL query or connection to SQL Server).

Possible causes of database failures in DPM include:

• An unusually high number of protection jobs are being processed on the DPM server at one time, and SQL Server is unable to handle the volume of requests in a timely manner. This is the most common cause of client time-outs and general network errors.

• A database or transaction log that DPM uses has run out of disk space.

• A database that DPM uses has entered an inconsistent state or has become corrupted.

• The SQL Server service is not running or is not configured correctly.

Some database failures in DPM are caused by transitory problems that may resolve themselves. Examples include insufficient resources, client time-outs, insufficient disk space for transaction logs, deadlocks in SQL Server, recoverable database errors, and timing issues.

Before you run diagnostics for this type of database failure, perform the following steps on the DPM server to ensure that the problem is not transitory.

To resolve issues that might cause a transitory database failure

1. Ensure that the SQL Server service is running. In Administrative Tools, open Services, and verify that the status of the MSSQL$Microsoft$DPM$ service is Started. If it is not, right-click the service and then click Start or Resume, as appropriate.

2. If this does not fix the problem, close and re-open DPM Administrator Console.

3. If this does not fix the problem, stop and restart the DPM service and the SQL Server service. (In most cases, restarting the DPM service will resolve the issue.) See “Verifying Status of DPM Service,” earlier in this chapter, for instructions.

If you experience database failures in DPM that are not transitory in nature, the issues can be complex. You will need to work with your SQL Server administrator to diagnose and resolve the related issues. Table 6.8 provides a starting point for resolving specific database errors.

Table 6.8   Database Errors

Error	To troubleshoot this error
Error 940: Unable to connect to the database because of a fatal database error. It is unlikely that the database itself has been damaged.	Ensure that the DPM instance of SQL Server (the MSSQL$Microsoft$DPM$ service) is running. Then use Windows Event Viewer to find information about related events.
Error 941: Unable to connect to the DPM database.	To resolve issues related to database connection failures: Ensure that the MSSQL$Microsoft$DPM$ service is running. Resolve transient issues that might be temporary database connection failures. Make sure that SQL Server is configured correctly. For information about configuring SQL Server for use with DPM, see the “Installing DPM” (https://go.microsoft.com/fwlink/?linkid=46357) chapter in the DPM 2006 Planning and Deployment Guide. For more information on troubleshooting connectivity issues in SQL Server 2000, see “How to troubleshoot connectivity issues in SQL Server 2000,” article number 827422 (https://go.microsoft.com/fwlink/?LinkId=51138), in the Microsoft Knowledge Base.
Error 942: Database integrity is in question because of a hardware or software problem.	If the integrity of a database is in question, contact your SQL Server administrator. You might need to repair or restore the database in SQL Server from backup media. Inform the administrator every time this error is encountered. Look at Windows Event Log for SQL Server/media failures. It is possible that the problem is in the cache only and not on the disk itself. If so, restarting SQL Server corrects the problem. In some cases, it may be necessary to restore the database. To resolve issues related to a database that may be corrupt Use Event Viewer on the DPM server to check for I/O problems at the time of the alert. I/O failures in the event log might explain why the database was corrupted. If that is the case, you might want to repair or replace the disk before restoring the database. To determine the extent of the database problem, perform a database check on the database for which integrity is in question. In SQL Query Analyzer, enter the following command: dbcc checkdb databasename Depending on the nature of the problem, you may need to repair or restore the DPM database. Some problems, such as indexing and caching problems, can be resolved by repairing the database or restarting SQL Server. Work with your SQL Server administrator to determine the best course of action.
Error 943: Unable to connect to the DPM database because the database is in an inconsistent state.	If DPM finds that a database is in an inconsistent state, the problem is unlikely to resolve itself. For help with troubleshooting the problem, contact Microsoft product support. For information, see Microsoft Help and Support (https://go.microsoft.com/fwlink/?linkid=45276).
Error 944: Database operation failed.	If you are experiencing client timeouts and general network errors that are possibly related to SQL Server being unable to handle the volume of requests, modify protection schedules for protection groups to stagger protection jobs. For more information, see “How to modify protection options” (https://go.microsoft.com/fwlink/?linkid=52008) in DPM Help. A high incidence of client timeouts may be a sign that the volume that stores your database files and transaction logs is highly fragmented. If needed, use Disk Defragmenter to defragment the volume. For more information, see “Disk Defragmenter: Defragment a Volume,” in Help and Support for Windows Server 2003. A shortage of disk space for a SQL Server database file or transaction log generates a warning or error in SQL Server, depending on how critical the shortage has become. If transaction logs overflow, the DPM service probably will shut down after one or more failed attempts to access the database. To resolve issues caused by a shortage of disk space for databases or transaction logs: Use Windows Event Viewer to get additional information about the problem. Use SQL Query Analyzer to get information about the size of the databases and the use of transaction log space. Enter the following commands: sp_helpdb — Reports the size of each database file. dbcc sqlperf (logspace) — Reports the current sizes of transaction logs. Shrink the database and transaction logs. In SQL Query Analyzer, enter the following commands: dbcc shrinkfile (databasenamelog.dat) — Shrinks the transaction logs for the specified database. dbcc shrinkfile (databasename_dat) — Shrinks the specified database file. If disk space is still insufficient, extend the volume that contains the files to ensure sufficient disk space for the transaction log during peak performance. This error can also occur if the administrator has deleted the database, taken the database offline, or detached the database for maintenance. If the database is offline or detached for maintenance, retry the operation after the database is brought online. If the database was deleted, restore the database from tape backup and then run DpmSync. For instructions, see the “Archiving and Restoring Data” chapter in this guide (https://go.microsoft.com/fwlink/?LinkId=46368).
Error 945: Unable to connect to the DPM database because of a general database failure.	For general database failures, ensure that the MSSQL$Microsoft$DPM$ service is running on the DPM server. Then use Windows Event Viewer to find information about related events. On a new DPM server, ensure that SQL Server is configured correctly. To resolve issues related to general database failures Ensure that the SQL Server service (MSSQL$Microsoft$DPM$) is running. Resolve transient issues that might be temporary database connection failures. Make sure that SQL Server is configured correctly. For information about configuring SQL Server for use with DPM, see the “Installing DPM” chapter (https://go.microsoft.com/fwlink/?LinkId=46357) in the DPM 2006 Planning and Deployment Guide. If general database failures persist, contact Microsoft product support for help with troubleshooting the problem. For information, see Microsoft Help and Support (https://go.microsoft.com/fwlink/?linkid=45276).

Additional Resources for Troubleshooting Database Issues

For information about:

• Configuring SQL Server for use with DPM, see the “Installing DPM” chapter (https://go.microsoft.com/fwlink/?LinkId=46357) in the DPM 2006 Planning and Deployment Guide.

• Backing up and restoring the databases that DPM relies on, see the “Archiving and Restoring Data” chapter in this guide.

• The sp_helpdb system stored procedure for SQL Server, see the entry by that name in the Transact-SQL Reference (https://go.microsoft.com/fwlink/?linkid=51140).

• The dbcc sqlperf and dbcc shrinkfile Database Console Commands for SQL Server 2000, see the “DBCC” entry in the Transact-SQL Reference (https://go.microsoft.com/fwlink/?LinkId=52528).

• Using event logs to identify problems, see the “Checking event logs: Common administrative tasks” topic in Help and Support for Microsoft Windows Server 2003.

• Problems with SQL Server, use SQL Server Enterprise Manager to review current activity, current locks, and current processes in SQL Server. For more information see, “Monitoring with SQL Enterprise Manager,” in SQL Server 2000 Books Online (https://go.microsoft.com/fwlink/?linkid=51137).

• Configuring and maintaining physical storage components in SQL Server 2000 to meet capacity, throughput, and performance requirements, see “Capacity and Storage Management” in the Microsoft SQL Server 2000 Operations Guide (https://go.microsoft.com/fwlink/?LinkId=51142).