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Weird issue with DNS and Cisco VPN

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Weird issue with DNS and Cisco VPN

demonjrules
I am dealing with a weird issue on 2 of my servers at the data center. Every once in a while I cannot connect to them (Ping, remote desktop etc) If I remote into one of my working servers I CAN ping/connect to them. The issue only happens to users using the Cisco VPN to connect to the data center.

To fix I remote into a working server and from there I remote into the non-working server and run a "ipconfig /registerdns" command. Does anyone else ever have this issue and if so, what did you do to permanently fix it?

Firewall is a Cisco ASA 5520
Machines are 2 Dell blade servers running Server 2003 r2
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    NetMan1958

    When you are unable to connect, are you trying to connect using the name or the ip address? Do the servers have static IP addresses?

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    demonjrules

    Servers have static IPs, connecting using name in host file and ip address does not work. Strangest problem I have ever run into.

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    NetMan1958

    Makes me wonder what the "ipconfig /registerdns" is really accomplishing. Have you tried running a capture on the inside interface of the ASA when you are experiencing the issue? This would tell you if the traffic is going across the VPN and being forwarded on to the servers and rather or not the servers are responding.

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    demonjrules

    That's a great idea! Next time it happens I will be sure to try your solution. Thanks!

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    0 Votes
    NetMan1958

    When you are unable to connect, are you trying to connect using the name or the ip address? Do the servers have static IP addresses?

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    0 Votes
    demonjrules

    Servers have static IPs, connecting using name in host file and ip address does not work. Strangest problem I have ever run into.

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    2 Votes
    NetMan1958

    Makes me wonder what the "ipconfig /registerdns" is really accomplishing. Have you tried running a capture on the inside interface of the ASA when you are experiencing the issue? This would tell you if the traffic is going across the VPN and being forwarded on to the servers and rather or not the servers are responding.

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    0 Votes
    demonjrules

    That's a great idea! Next time it happens I will be sure to try your solution. Thanks!