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Tiemooowh_92118's avatar
Tiemooowh_92118
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May 16, 2011

Exchange 2007 RPC over HTTPS latency

Dear,

 

 

Last week we've been moving our load balanced services from our old loadbalancers to our brand new F5 LTM's. All services seem to work smooth, however the latency on the Exchange 2007 RPC connections is now around 150ms (where it was around 15ms before).

 

 

 

I've configured the F5's without SSL offloading (we still want Exchange to do the SSL termination, not the LTM). Our operational Virtual Server I've configured based on the Deployment Guide Exchange 2007 (revision 1.5). Last week I tried changing some settings in a replica VS (with another virtual IP), to limit the latency on the line, but none of the changes I performed had impact on the latency.

 

 

 

Has someone had this issue before? Or does someone know how to resolve this?

 

 

 

Kr,

 

Timo

 

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  • Michael_Koyfma1's avatar
    Michael_Koyfma1
    Icon for Cirrus rankCirrus
    May 16, 2011
    Just curious, why are you not terminating SSL on F5? Are you using a standard VS type for OutlookAnywhere connections? If so, can you please try to change TCP profiles to tcp-lan-optimized on both client and server side?

     

  • Tiemooowh_92118's avatar
    Tiemooowh_92118
    Icon for Nimbostratus rankNimbostratus
    May 17, 2011
    Hi Michael,

     

     

    Since this is a migration from a production environment with over 8000 users, initial fase was just porting functionality to our F5. In second fase we were planning to do a rollout of Exchange 2010 and do termination onto the F5 servers. I have been playing around with the TCP profiles, but none of them seem to have an effect on the performance.

     

     

     

    Kr,

     

    T

     

  • Tiemooowh_92118's avatar
    Tiemooowh_92118
    Icon for Nimbostratus rankNimbostratus
    May 19, 2011
    Hi Michael,

     

     

    Opened an F5 case as well, seemed to be that the Virtual Server should be in Performance Layer 4 mode (instead of the Standard mode it was in). All problems were gone after this.

     

     

    Kr,

     

    T
  • Michael_Koyfma1's avatar
    Michael_Koyfma1
    Icon for Cirrus rankCirrus
    May 19, 2011
    That will work while you're not doing SSL termination on F5, but when when you switch to do SSL offload, you will need to go back to the Standard virtual type. I recommend trying a Standard virtual type now with tcp-lan-optimized profiles on both Client and Server side and see how the performance is in your case.

     

     

     

  • Tiemooowh_92118's avatar
    Tiemooowh_92118
    Icon for Nimbostratus rankNimbostratus
    May 19, 2011
    Hi Michael,

     

     

    In standard mode none of the tcp profiles seem to make a difference.. Tried them all..

     

     

     

    T