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Rusty_M_140798's avatar
Rusty_M_140798
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Aug 15, 2014

SSL VPN Disconnect Issue

We currently have an issue with our SSL VPN connection disconnecting on random intervals. I do have a open support case and unfortunately not making any drastic headway, so reaching out here to see i...
application delivery
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deployment
performance
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  • Matti_63169's avatar
    Matti_63169
    Jun 02, 2016

    Check the DNS settings of the F5 and make sure it can resolve the sslvpn fqdn.

     

    Background: We had similar issues, the PPP tunnel kept randomly closing and opening a new one, which caused the clients to reconnect, which in turn caused traffic not flowing while the PPP tunnel did a new handshake.

     

    There were no evidence in the LTM log why this happens, but the Edge client log revealed that DNS lookup for the APM endpoint (LTM VIP) didn't resolve. The client machine actually could resolve it, but the F5 itself couldn't. After changing the DNS servers in F5 to ones that resolved correctly the problem seems to have been solved.

     

Shain_Singh_846's avatar
Shain_Singh_846
Historic F5 Account

In which direction do you get the Zero Windows? Setting the timeout to zero can have other unexpected behaviour.

 

The log shows an almost 10min timeout for your disconnection. Have you gone through the Access Policy settings to see whether there is anywhere a disconnect is being set? (this is typically in the first option page of the Access Policy)

 

Rusty_M_140798's avatar
Rusty_M_140798
Icon for Nimbostratus rankNimbostratus
Aug 27, 2014
Sorry for the delay in my response, we are seeing the Zero Window on the client side capture. Currently we have the setting set to the default of 2000 since changing it did not yield any results. Everything on the access policy is default, the log attached is just one example sometimes its 10 min another time its 30 min then its 2 hours. No real time variable available.