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James_Anderson's avatar
James_Anderson
Icon for Nimbostratus rankNimbostratus
Nov 12, 2025

Cannot automatically add the LTM virtual server to DNS

Hi Team,

 

I'm having an issue while configuring GTM. DNS is able to connect to the BIG-IP LTM, but it cannot automatically add the LTM virtual servers to DNS. I checked the iqdump, and it does contain information related to the LTM virtual servers, but I still don't see any VS entries in the GUI.

 

iqdumpThe BIG-IP DNS server is showing 0 virtual serversLTM VS is Available

After that, I tried to manually add the LTM virtual servers, but it showed this error message: 'no reply from big3d: timed out'.

 

GTM DNS

4 Replies

  • James_Anderson's avatar
    James_Anderson
    Icon for Nimbostratus rankNimbostratus
    Nov 12, 2025

    Hi,

     

    Checking the iqdump shows that TCP port 4353 is allowed between the BIG-IP DNS system and the target BIG-IP systems. There is no router or firewall between the DNS and the LTM, so there is no network address translation involved. I have already enabled these features, but I still don't see any VS entries in the GUI.

    Configure global auto-discoveryConfigure virtual server auto-discoveryConfigure link auto-discovery