Planning DFS and FRS Security

Applies To: Windows Server 2003, Windows Server 2003 R2, Windows Server 2003 with SP1, Windows Server 2003 with SP2

When planning to secure DFS namespaces and content replicated by FRS, follow these guidelines:

  • Use NTFS permissions to secure DFS targets. If you are using FRS to replicate DFS link target information, any permission changes you make on one member of the replica set replicate to other members. If you are not using FRS for automatic replication, you must set the permissions on targets and manually propagate any changes that occur.

  • When setting NTFS permissions, always use the path of the physical folder (\\servername\sharename) instead of navigating through the DFS namespace to set permissions. This is especially important when you have multiple link targets for a given link. Setting permissions on a folder by using its DFS path can cause the folder to inherit permissions from its parent folder in the namespace. In addition, if there are multiple link targets, only one of them gets its permissions updated when you use the DFS path.

  • If you plan to use share permissions, note that FRS does not replicate share permissions; therefore, you must plan to implement identical share permissions for each shared folder in a replica set. If you do not, users might have inconsistent access to shared folders across the network.

  • To prevent the spread of viruses in read-only FRS-replicated content, give the appropriate groups the NTFS Read & Execute permission, create a group for administrators who update content, and assign that group the NTFS Modify permission. Do not grant permissions to the Everyone group. For additional recommendations, see "Permissions on a file server" in Help and Support Center for Windows Server 2003.

  • For FRS-replicated content, you must use antivirus programs that are FRS compatible and that do not change the security descriptor of files. For more information about FRS compatible antivirus programs, see article Q815263, "Antivirus, Backup and Disk Optimization Programs That Are Compatible with the File Replication Service." To find this article, see the Microsoft Knowledge Base link on the Web Resources page at

  • You must have permissions on the DFS configuration object in Active Directory to add and delete roots to a domain-based DFS namespace.

  • You can create DFS link targets that point to shared folders containing data that is encrypted by using EFS. However, you cannot use FRS to replicate those files among multiple link targets.

  • Do not enable the RestrictAnonymous registry value on DFS root servers. Doing so restricts anonymous access and causes DFS referral failures. This registry value is also part of the HiSecWeb security template, which is designed to help secure Internet Information Services (IIS) at the operating system level. For more information about the RestrictAnonymous registry value, see article Q246261, "How to Use the RestrictAnonymous Registry Value in Windows 2000." For more information about the HiSecWeb template, see article Q316347, "IIS 5: HiSecWeb Potential Risks and the IIS Lockdown Tool," in the Microsoft Knowledge Base. To find these articles, see the Microsoft Knowledge Base link on the Web Resources page at