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Zdenda's avatar
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Jan 17, 2012

OWA - echange web app problem with IE

Hi all,


We have OWA running on its own VIP, SSL termination is done on destination servers.


We are using quite simple config - round robin, source address persistence, tcp profile with 30 min. timeout.



We have problem even with displaying login page on TMG. On FF it works quite ok, on IE it mostly doesn't work, occasionally I see login page in also in IE. When I try it directly to TMG server, it works also with IE.



I am not using any http profile etc.



Do you have any idea?


Thanks a lot,




4 Replies

  • Hi Zdenek,



    I'd open a case with F5 Support on this. They'll be able to help you capture tcpdumps to determine what's failing here.



  • Ha,


    we found the reason of this. It was caused by flooding checking on TMG server. And because we use sNAT on LB, TMG though that is under DOS attack or something like that (because of only one src IP), so it dropped almost all connections.



    Hope it help to some others




  • Hi Zdenda,


    Will you share how you found it and what you did to over come this problem????



  • Hi, sorry, I don't know the details how exchange guys found this. They have probably running some local FW on TMG server which was dropping connections from the only one source IP - sNAT IP on LB.


    And its solved by excluding LB IP from this checking on TMG server.