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jmcmurchie_1380's avatar
jmcmurchie_1380
Icon for Nimbostratus rankNimbostratus
Jun 18, 2015

DNS resolution failing over VPN

We have recently seen a failure of DNS resolution over our VPN. Clients who connect to the VPN show the correct windows domain DNS servers. The servers are properly resolving names within the domain (local connections).

 

But, when VPN clients try to locate resources by name there is no resolution. If they enter the IP of the domain resource they can reach them.

 

I am not aware of any changes to the LTM or the domain DNS servers. We waited for a network quiet period and rebooted the f5, no change to the situation. We are on version 11.6 of the OS.

 

Any ideas?

 

application delivery
BIG-IP Access Policy Manager (APM)
LTM
management
microsoft
security

4 Replies

  • amolari's avatar
    amolari
    Icon for Cirrostratus rankCirrostratus
    Jun 19, 2015
    using split tunnelling of force all traffic in the tunnel?
  • boneyard's avatar
    boneyard
    Icon for MVP rankMVP
    Jun 21, 2015
    i would go to network troubleshooting, check if the DNS query ends up at the server, if the server answers and if the reply gets to the client.