Using WNLB or external load balancer? RRS feed

  • General discussion

  • I'm an Exchange guy and over the past few years the best practice for load balancing shifted from cheap but cripled WNLB to now affordable hardware load balancers. The main reasons not to use WNLB are:

    - Port flooding issues, requires additional configuration on network devices.
    - Limited affinity features, supports source IP only. Not very usefull when incoming traffic is NAT-ted.
    - Not service aware, as long as a servers can be pinged WNLB will direct user request to the server. Even if the relevant Windows services have been stopped...
    - And of course scalability, although only relevant for very large deployments.

    Now with UAG WNLB seems to a valid option. The use of WNLB is cheap because no additional purchases are necessary and monitoring and configuration of WNLB is integrated in the UAG Console.

    What does the UAG community see as best practice to load balance UAG servers? Do customers see WNLB as an acceptable option for UAG? Does the external load balancer have other advantages besides scalability?

    Did my post help? Please use "Vote As Helpful", "Mark as answer" or "Propose as answer". Thank you!

    Thursday, April 11, 2013 12:24 PM

All replies

  • Just my perspective based on experience - I install DirectAccess on both the UAG and Server 2012 platforms all the time, and almost everyone goes with WNLB. It's built with it in-box just like you said, it works well, and it's easier to setup than hardware LBs. Especially with Server 2012, there have been quite a few problems over the past few months with getting the hardware LBs to work with DirectAccess. WNLB just works like you tell it to.

    Scalability isn't really that much of an advantage anymore either. You can join eight nodes together with WNLB, and with the ability to put many thousands of users on a single node (with the hardware I install anyway - our own appliances) it would be a pretty rare customer that couldn't do their full user load using WNLB.

    Monday, April 15, 2013 3:50 PM
  • I fully agree with the scalability point, that should be no issue for almost all deployments. I see I need to reconsider my point of view regarding WNLB, at least when it is to load balance UAG.

    Thanks for your input!

    Did my post help? Please use "Vote As Helpful", "Mark as answer" or "Propose as answer". Thank you!

    Wednesday, April 17, 2013 8:40 AM