Server 2003 R2 and possible DFS replication limitations?

Posted on 2011-05-02
Last Modified: 2012-06-27
Hi, we're using DFS to replicate 2 very large Folder shares between 2 sites.  The shares contain 1000's of folders and probably around 1,000,000+ files each.

If i run a DFS managment helath check everything looks fine, but we were wondering are there limitations with how much DFS can handle?  The Servers are running 2003 R2 Std edition.


Question by:kswan_expert
    LVL 2

    Expert Comment

    You can find the limits here:

    Microsoft Supported DFS, Offline Files, and FRS Deployments
    Description      Limit or Recommendation*      Explanation

    Number of characters in path limit

    Fewer than 260 characters

    Win32 application programming interfaces (APIs) have a maximum path limit of 260 characters. Applications fail when trying to access a namespace that goes beyond that limit. If the path length of a DFS namespace exceeds the Win32 API limit of 260 characters, users must map part of the namespace to a drive letter and access the longer namespace through the mapped drive letter.

    Number of DFS roots per server running Windows Server 2003 Standard Edition

    One, unless a hotfix is installed

    Windows Server 2003 Standard Edition, is limited to one root per server. To create multiple domain-based namespaces on a server running Windows Server 2003 Standard Edition, install the hotfix described in article 903651 in the Microsoft Knowledge Base on the Microsoft Web site.

    Number of DFS roots per server running Windows Server 2003 Enterprise Edition, or Windows Server 2003 Datacenter Edition


    There is no limit to the number of DFS roots you can create on a server running Windows Server 2003 Enterprise Edition, or Windows Server 2003 Datacenter Edition. However, as you increase the number of roots per server, the DFS service takes longer to start and uses more memory.

    Number of root targets per domain-based DFS root

    No fixed limit

    If you do not enable root scalability mode, we recommend using 16 or fewer root targets to limit traffic to the server acting as the primary domain controller (PDC) emulator master.

    Number of links per DFS namespace

    5,000 for domain-based DFS

    50,000 links for stand-alone DFS

    When the number of links exceeds the recommended limit, you might experience performance degradation when making changes to the DFS configuration. For stand-alone DFS, namespace initialization after server startup might also be delayed.

    Size of each DFS Active Directory object (applies to domain-based DFS namespaces only)

    5 megabytes (MB)

    The size of the DFS Active Directory object is determined by the number and path length of roots, links, comments, and targets in the namespace. We recommend using no more than 5,000 links in a domain-based namespace to prevent the DFS Active Directory object from exceeding 5 MB. Limiting the size of the Active Directory object is important because large domain-based DFS configurations can cause significantly increased network traffic originating from updates made to those roots, links, and targets.

    Maximum amount of data that the File Replication service (FRS) can replicate in a domain-based DFS namespace

    See recommended limits at;en-us;840675.

    It is important that you review the FRS design guidelines before enabling replication. See the chapter "Designing and Deploying File Servers," in the Microsoft Windows Server 2003 Deployment Kit. Doing so will help you optimally deploy and configure FRS for your environment.

    Accepted Solution

    Cheer but that's old DFS, I'm looking for "R2" limits.

    Author Closing Comment


    Write Comment

    Please enter a first name

    Please enter a last name

    We will never share this with anyone.

    Featured Post

    6 Surprising Benefits of Threat Intelligence

    All sorts of threat intelligence is available on the web. Intelligence you can learn from, and use to anticipate and prepare for future attacks.

    Suggested Solutions

    So you have two Windows Servers and you have a directory/folder/files on one that you'd like to mirror to the other?  You don't really want to deal with DFS or a 3rd party solution like Doubletake. You can use Robocopy from the Windows Server 200…
    ADCs have gained traction within the last decade, largely due to increased demand for legacy load balancing appliances to handle more advanced application delivery requirements and improve application performance.
    Need more eyes on your posted question? Go ahead and follow the quick steps in this video to learn how to Request Attention to your question. *Log into your Experts Exchange account *Find the question you want to Request Attention for *Go to the e…
    Sending a Secure fax is easy with eFax Corporate ( First, Just open a new email message.  In the To field, type your recipient's fax number You can even send a secure international fax — just include t…

    759 members asked questions and received personalized solutions in the past 7 days.

    Join the community of 500,000 technology professionals and ask your questions.

    Join & Ask a Question

    Need Help in Real-Time?

    Connect with top rated Experts

    13 Experts available now in Live!

    Get 1:1 Help Now