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Rusty_M_140798's avatar
Rusty_M_140798
Icon for Nimbostratus rankNimbostratus
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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TMOS
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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.

     

Francisco_Abel_'s avatar
Francisco_Abel_
Icon for Nimbostratus rankNimbostratus
Jul 04, 2018

Hi all,

 

Another possibility which I observed in the past regarding the following scenario: - Split tunneling enabled - ProxyPAC enabled with corporate URL for PAC file - Let's suppose than both the DNS and the hostname for the mentioned URL are routed thru the VPN

 

In case that, after establishing the VPN connection, the Edge Client cannot download the PAC file from the configured URL, the connection closes prematurely.

 

At the moment you fix the connectivity problem to the PAC URL, the VPN connection establishes successfully and the problem dissapears.

 

Francisco