topic Re: FTD DNS management not working in Network Security

FTD DNS management not working

swater — Wed, 26 Oct 2022 07:59:59 GMT

Hello,

Recently I've provided a test FTD1010 with image 7.2.1-40. The issue is that my DNS is not working from the Management interface.

In FTD cli I can do a "ping system 1.1.1.1" but I can't do a "ping cisco.com", it ends in "ping: cisco.com: Temporary failure in name resolution"
When I do a "show network" I get to see, among other things, "DNS from router : enabled".
From another working Firewall it states "DNS from router : disabled"
How do I change the setting "DNS from router"?

Any help is appreciated

Sjoerd

Re: FTD DNS management not working

manabans — Wed, 26 Oct 2022 00:49:35 GMT

'DNS from router' could be due to management traffic passing through the FTD data interface.
If you are using the data interfaces as the gateway, verify that you have the required routes. You need a default route for 0.0.0.0. You might need additional routes if the DNS server is not available through the gateway for the default route.

Refer topic 'Troubleshooting DNS for the Management Interface' from the below document,
https://www.cisco.com/c/en/us/td/docs/security/firepower/720/fdm/fptd-fdm-config-guide-720/fptd-fdm-mgmt.html#task_88DEC3AB778D4F6EB78B6FD410A9B8D0

Re: FTD DNS management not working

swater — Wed, 26 Oct 2022 08:00:41 GMT

Hi Manabans,

Thx for you reply!
Management interface indeed uses the data gateway. And it works, because I can succesfull do a "ping system 1.1.1.1", however a "ping system cisco.com" doesn't work and leave me with the message, "ping: cisco.com: Temporary failure in name resolution".

Kind regards,
Swater

Re: FTD DNS management not working

kenhgn — Fri, 02 May 2025 14:31:03 GMT

This information helped me with my problem. Thank you so much.

Ken