Cisco Support Community
Showing results for 
Search instead for 
Did you mean: 

Welcome to Cisco Support Community. We would love to have your feedback.

For an introduction to the new site, click here. If you'd prefer to explore, try our test area to get started. And see here for current known issues.

New Member

Anyconnect - Anyconnect IPv6 DNS Entry

Hi all,

I have been looking for some level of information related to Anyconnect ipv6 & DNS to no alive.

my customer is currently facing with an issue, once the Laptop goes in to sleep mode and awakes within their local network the trusted dns does not work as the IPv6 DNS entry is not released.

let me explain

per customer's research this issue is related to DSL clients with  Speedport DSL or Fritzbox DSL box. they are announcing IPv6 settings in some version of their OS. If the client  on this environment put their notebook into sleep mode and reopen it within customer local network, the trusted dns does not work as the IPv6 DNS entry is not released. This brings the AC to the assumption that it is not within the trustet network and tries to open the VPN connection.
There is a workaround announced by cisco to enter a " *.* " to the trusted dns server list but this is not a solution as the IPv6 only clines will appear soon. As these homeoffice DNS servers are then recognized as trusted the vpn enforcement will not apply.

any idea on this or do I need to open TAC case.

thank in advance


  • VPN
This widget could not be displayed.