Backup is growing large and running slow, server runs DFS

SUMMARY

Backup is growing large and running slow, server runs DFS. Also valid for any writers that should be excluded from system state. (WDS, DFS, etc)

ISSUE

Purpose

This article addresses that causes a Windows system state backup to grow inordinately large and backup is taking a long time to complete.

During a file-level backup of any type (master, differential or incremental) a system state backup is also taken.  When a Windows server is using DFS (Distributed File System), this system state backup can grow very large and cause the backup to take a long time.

Cause

The system state backup will included data within the volume using DFS, cause large system state backups and long backup times.

Resolution

To resolve this, the DFS writer must be excluded from the system state backup.

vssadmin list writers

Writer name: 'FSRM Writer'
Writer Id: {12ce4370-5bb7-4c58-a76a-e5d5097e3674}
Writer Instance Id: {74d6ad79-fa10-460c-ac44-21f343b92870}
State: [5] Waiting for completion
Last error: No error

Writer name: 'DFS Replication service writer'
Writer Id: {2707761b-2324-473d-88eb-eb007a359533}
Writer Instance Id: {c9aa68b1-c0a5-4201-8a0c-746c38f9f63a}
State: [5] Waiting for completion
Last error: No error
 

[System State]
IncludeWriterFilesInMaster={12ce4370-5bb7-4c58-a76a-e5d5097e3674} , {2707761b-2324-473d-88eb-eb007a359533}

1. Run the command below to view all of the VSS writers.
2. Open the Unitrends Agent’s master.ini configuration file located on the client-server in the \PCBP\ directory.
3. Add a System State section and the IncludeWriterFilesInMaster field, which references the Writer ID for both the FSRM and DFS writers.