Load balancing in a scaled single side edge server topology RRS feed

  • Question

  • Reading the best practises for de Edge Server deployment (Designing Your Perimeter Network for Office Communications Server 2007) I have one question releated to the load balancing of the Audio/Video Edge Servers.




    On page 28 the following is written:


    "When you use a load balancer for your edge servers, you should configure the load balancer to use Destination NAT (DNAT), not Source NAT (SNAT). This fulfills the requirement of a publicly routable IP address for the A/V Edge Server."


    For the A/V configuration this means that the A/V Load Balancer VIP and the external interfaces of each A/V edge server needs a publicly routable IP. In the sample drawing on page 21 all the IP addresses of the A/V Edge interfaces are in the same subnet.


    Should this be the same for the internal interfaces of the A/V Edge servers as well? I can imagine that if you put the A/V load balancers in another subnet (with a different IP) the audio/video streams can not be routed properly anymore.


    I wonder if any one has done the configuration of the load balancers (on both sides) for the A/V edge servers before and can share some experiences.




    Thursday, December 4, 2008 9:57 AM

All replies

  • You can use SNAT in this situation.  But DNAT works find as well.  I have seen issues with both configurations - when the LB is not configured correctly or if there was routing issues in the DMZ.  Mostly I have seen SNAT in the DMZ.  But you would only put Public IP's on the Public facing Network Interfaces. 

    Monday, December 29, 2008 1:39 AM