Forum Discussion

Zdenda's avatar
Icon for Cirrus rankCirrus
Dec 13, 2011

Link to VIP doesnt work correctly when DNS name is used

Hi all,


I am lost in this case, when client is accessing web page with login window:



When client goes to VIP (to IP address/URI), he gets login window, then log on to system without problem. Everything is OK.



When client goes to VIP (to DNS name/URI), he gets login window, but when fill username/password and click enter, he get login window again (like clicking reload).



DNS record is OK, persistence is turned on.



Please help me, this is urgent and so weird..


thanks a lot,




5 Replies

  • Hi Zdenek,



    This seems to be an app level issue. Do you see the same issue if you test directly to the web app?



    If it's urgent, I suggest opening a case with F5 Support and ask them to help compare a trace of a test by IP with a trace testing the hostname.



  • Hi Aaron,


    I also think that its app level issue, I tried to replace host from DNS name to IP address in http header, it didnt help.


    And no, I dont see the same issue when I am testing it directly.



    thx for opinion




  • If you disable all but one pool member does the DNS name work?



  • I tried this also, didnt help.



    Anyway final result is here, this was caused by IE, with firefox this problem doesnt appear.


    I dont know why IE behave like this, but it is so (regardless of using proxy or not)


    thanks for your time Aaron


  • Hamish's avatar
    Icon for Cirrocumulus rankCirrocumulus
    Tcpdump the traffic between the browser and vs, and between the bigip and backend and see what actually gets sent and recieved.


    Hopefully youre not running snat on the vs, so you'll be able to filter directly on the client ip (Disable any proxy too).