Windows Server 2008 introduced DFS-R as a new technology for Sysvol replication . It this post I’ll illustrate the migration from the old , commonly used replication technique [ File Replication Service – RFS ] to the newly introduced replication technique [ Distributed File System Replication – DFS-R ].
First of all a question arise “Why to migrate your sysvol ?”
The answer simply is , by using DFS-R for your sysvol you gain the following benefits :
- Efficient, scalable and reliable file replication protocol which has been tested extensively to ensure data consistency in multi-master replication scenarios.
- Differential replication of changes to files using the Remote Differential Compression (RDC) algorithm, which enhances efficiency in branch office scenarios.
- Flexible scheduling and bandwidth throttling mechanisms.
- Self-heals from USN journal wraps and database corruptions – end user intervention and monitoring requirement is minimal.
- Provides a new UI management tool (MMC snap-in) for ease of administration.
- Provides built in health monitoring tools for ease of monitoring deployments.
- Improved support for Read Only Domain Controllers.
Ok , let’s get our hands dirty ; First of all you must ensure that all your sysvol replicas are consistent & healthy , which can be verified using the following command :
You will got something like below.
Note :If any errors present , trace and solve it before proceeding with migration.
During sysvol migration to DFS-R , sysvol passes though the following stages :
- Preparation Phase (State)
- Redirected Phase (State)
- Elimination Phase (State)
In order to proceed with migration, execute the following command – is series – from an elevated command prompt:
- dfsrmig /SetGlobalState 1
- dfsrmig /SetGlobalState 2
- dfsrmig /SetGlobalState 3
Post each of the above commands you should run “dfsrmig /GetMigrationState” to ensure success of each stage [ Confirm that the new flag has been replicated to all domain controllers ]
You may find it easier to go directly and run “dfsrmig /SetGlobalState 2” from the beginning to go directly to “redirected state” through “preparation state” which is feasible. Although you can proceed with “dfsrmig /SetGlobalState 3” , but it is not recommended , as you can easily revert back during any phase prior than elimination phase ( 3 ) using:
dfsrmig /SetGlobalState 0
Finally , here are some tips to avoid slowness in DFS replication.