Dell NetWorker 19.9 Administration Guide

PDF

Troubleshooting block based backup and recovery issues

This section lists the common issues with the block based backups and recoveries and provides workarounds for these issues.

Table 1. Troubleshooting block based backup and recovery issues
Error message or Issue	Resolution
Block based full backup fails on ext4 13.5 TB volume size when block size is 1024 (1k) with_meta_bg.	In the Policy Action Wizard, increase the Inactivity Timeout from the default value 30 to 60 or 120 to have a successful full backup.
Block based backups are only supported with Client Direct.	In the Client Properties dialog box, select Client Direct.
VSS OTHER: ERROR: VSS failed to process snapshot: The shadow copy provider had an unexpected error while trying to process the specified operation. (VSS error 0x8004230f) 90108:save: Unable to save the SYSTEM STATE save sets: cannot create the snapshot.	Ensure that there is no recover session running on the client.
No save sets clone to clone device.	Block based backups clone only full backup save sets. Block based backups do not clone incremental backup save sets.
Unable to construct the recover list from input file.	Perform an image recovery if applicable. Otherwise, select all the files except the system files such as, System Volume Information and Recycle Bin to perform a file level recovery.
Failed to recover save set with error: To perform the recovery of a block based backup save set, the device must be enabled for Client Direct.	In the Client Properties dialog box, select Client Direct.
Though the size of a target volume is more than the size of a source volume, after performing an image recovery, the target volume file system can use its volume only up to the same size as the size of the source volume.	To enable the target volume file system to use its volume to the actual size, extend the file system: In the command prompt, type `diskpart` and press <Enter>. In the DISKPART command prompt, select the target volume to extend the file system by running the following command: `select volume <target_volume>` For example, select volume G: Extend the file system by running the following command: `extend filesystem` Exit from the DISKPART command prompt by running the following command: `exit`
Block based backup failed partially, when parallel save streams is enabled: 9904:nsrmmdbd: access denied to media database, `SYSTEM' on `hostname' must have 'Operate NetWorker' or 'Change Application Settings' privilege 90096:save: save of 'E:\' to 'hostname' failed: access denied to media database, `SYSTEM' on `hostname' must have 'Operate NetWorker' or 'Change Application Settings' privilege	To perform parallel save streams enabled backups for block based backup volumes: In NMC, under Server, select User Groups. Right click Application Administrators and select Properties. In the User Group Properties Application Administrators window, under Users, add user=system,host='hostname'.
Block based backup failed partially, when parallel save streams is enabled: 155185:save: Successfully closed the backup session 158612:save:GUID of the current plex and previous plex for the save set '<2>C:\' are different. 12/11/20 10:12:55.884595 VHDx format generator successful. 12/11/20 10:12:55.884595 NsrBlockSave Failed. 12/11/20 10:12:55.884595 Initiating nsrblockbase failed for save set 'C:\'.	For block based backup to succeed, ensure that the following requirements are met: Create a separate pool. The pool must contain only one backup device. Perform all backups of a client on the same backup device. However if more clients are backed up, create a separate group. For more information about Parallel Save Streams (PSS), see Dell NetWorker Performance Optimization Planning Guide.
Block based backup driver failed to load in RHEL/CentOS version 8 or above with the below message in systemctl bbb status "insmod: ERROR: could not insert module /lib/modules/<kernel version>/extra/nsrbbb.ko: Permission denied".	If SELinux is configured to enforce, BBB driver will fail to load. Configure "SELinux" to "disabled" for RHEL/CentOS version 8 or above.
Incremental Block based backup will fall back to full backup with message in save logs "Driver is not available for the volume '<volume-name>'. Falling back to level full".	For RHEL/CentOS version 8 and above, SELinux should be turned off to load BBB driver for successful incremental block-based backup.