Troubleshooting Manual Replica Creation

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Published : September 27, 2005

Manual replica creation is the process an administrator uses to create the initial replica by transferring the data to the DPM server from removable media such as a tape backup, rather than replicating from the file server to the DPM server over the network. This process is similar to restoring a replica to a DPM server from tape backup, which is explained in the Archiving and Restoring Data (https://go.microsoft.com/fwlink/?LinkId=46368) chapter in this guide.

The specific steps for creating a manual replica depend on the backup software that you use to transfer the data. See the Featured Technical Content area of the DPM product site (https://go.microsoft.com/fwlink?linkid=33686) for white papers with guidelines for using backup products with DPM.

When you create a manual replica, it is critical that you retain the same directory structure and properties (time stamps and security permissions) as those for the data that you are protecting. For guidance in selecting the specific settings, consult your backup software documentation and the white papers included in the Featured Technical Content area of the DPM product site.

If the replica is created correctly, the directory structure of the ReplicaDir folder of the replica on the DPM server will map to the directory structure of the volume being protected.

Some common errors that can occur during manual replica creation include:

  • Transferring the data by using a flattened directory structure that does not include the full path of the source data on the protected file server. The replica must be created by using the path to the data as it exists on the file server. If you create the replica with an incorrect path, delete the replica data and create the replica again. If you have already started synchronization with consistency check, you need to do the following:

    • Remove the protected volume or share from the protection group and choose to delete the replica

    • Add the volume or share to the protection group

    • Manually create the replica again.

    In the case of a flattened directory structure, synchronization with consistency check can potentially synchronize the entire replica over the network from the file server, consuming valuable network bandwidth and CPU resources.

  • Transferring the data to an incorrect directory, causing the replica hierarchy to be incorrectly created. The replica must be created in the location that is specified in the Properties pane in DPM Administrator Console when you select manual replica creation. If you transfer the data to an incorrect location, you can use FsPathMerge to move the data or you can delete the replica data and create the replica again. If you have already started synchronization with consistency check, you need to do the following:

    • Remove the protected volume or share from the protection group and choose to delete the replica

    • Add the volume or share to the protection group

    • Manually create the replica again.

    In the case of an incorrect replica hierarchy, synchronization with consistency check can potentially synchronize the entire replica over the network from the file server, consuming valuable network bandwidth and CPU resources.

  • Recreating junction points rather than using existing junction points. This is an issue when you are using a tape backup that was created from a DPM server. If you do not choose to use existing junction points during the restore operation, data may be restored to the incorrect path. If this occurs, manually delete the data and the path, and then manually create the replica again.

  • Failing to restore security settings when you restore the data. The backup of the data includes the security settings of the source data. If you restore the data from the backup without restoring the security settings, the correct access control lists (ACLs) will not be configured on the files and folders until synchronization with consistency check completes successfully. Incorrect replica data security settings can allow non-privileged users to have access to the data. Failure to restore the security settings also means that synchronization with consistency check will take longer to complete and transfer more data over the network.

  • Changing the file and folder time stamps, because of user error or by-design behavior of the backup software. For example, backup software might set the time stamp of restored files and folders to the restore time rather than using the time stamp that the files and folders had at the time of backup. Incorrect time stamps will cause synchronization with consistency check to take longer to complete and transfer more data.