Max size of R2 DFS

Discussion in 'File Systems' started by G Park 3, Sep 7, 2006.

  1. G Park 3

    G Park 3 Guest


    According to KB840675 the maximum limit for DFS/FRS data under 2000 or 2003
    servers is 64Gb.

    If this is the case (assume this limit is for all data although with a max
    staging area size of 2TB perhaps the max is not per root but something else)
    what are the limits under R2 DFS?

    The total data I would be looking to replicate between two geographically
    diverse Windows servers would be at least 600Gb today to 2TB in the next two
    G Park 3, Sep 7, 2006
    1. Advertisements


    DFS Replication scalability guidelines
    Updated: July 25, 2006
    DFS Replication is a highly scalable replication engine that was built to
    efficiently replicate large sets of content over wide area networks. The
    following list provides a set of scalability guidelines that have been
    tested by Microsoft:

    • Each server can be a member of up to 256 replication groups.

    • Each replication group can contain up to 256 replicated folders.

    • Each server can have up to 256 connections (for example, 128 incoming
    connections and 128 outgoing connections).

    • On each server, the number of replication groups multiplied by the number
    of replicated folders multiplied by the number of simultaneously active
    connections must be kept to 1024 or fewer.

    • A replication group can contain up to 256 members.

    • A volume can contain up to 8 million replicated files, and a server can
    contain up to 1 terabyte of replicated files.

    • The maximum tested file size is 64 gigabytes.


    Now, my long-winded clarification on the file size bullets:

    - The 8 million file, 1 terrabyte limit

    DFSR has no real limit on the size of files that can be replicated.
    The DFSR Jet database has a theoretical limit of 32TB, with roughly 8TB
    for file ID records.
    The assumption in the limit is that with a file ID records taking up to 1KB
    most, the upward practical limit would be 8 million files.
    In practical experience at MS, 50 million files have been replicated in one
    2-server replication group - the Jet DB takes up 20GB, and the data over
    1TB - as
    you can see here, the 1K max size of each file ID record is not shown to be
    in reality.

    The real limitation here with 8 million files would be performance - the MS
    above is primarily static data.
    Some factors noted by Dev that can affect replication performance with this

    * Bandwidth throttling settings
    * Speed of the network
    * Ability to compress changes using RDC and whether cross-file RDC is used
    * Size of the staging folder quota
    * Speed of the disk subsystem
    * Whether you have optimized the servers by placing the replicated folder
    staging folders on separate disks

    - The 64GB file size limit

    This is just the largest file size that was tested. With a properly sized
    area, it's conceivable that the file could be much larger. typically, files
    large are databases, which should not be replicated.


    All make sense?


    Ned Pyle
    Microsoft Enterprise Platforms Support

    All postings on this newsgroup are provided "AS IS" with no warranties, and
    confer no rights.
    For more information please visit to find terms of use.
    Ned Pyle [MSFT], Sep 7, 2006
    1. Advertisements

  3. G Park 3

    G Park 3 Guest

    Makes perfect sense, thanks for taking the time to explain it.

    G Park 3, Sep 7, 2006
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.