cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
833
Views
10
Helpful
9
Replies

DNS on a Cisco 2900 router (continued)

roncro
Level 3
Level 3

Hello,

 

Still trying to get DNS on a Cisco 2900 router to work.

 

Interesting part is that when I do reverse lookups, I get an immediate answer.

 

# nslookup 192.168.23.2 192.168.2.37
2.23.168.192.in-addr.arpa name =  mytestpc.

Authoritative answers can be found from:

 

 

So it seems that I might be missing something.

I did set "ip domain name localdomain" I don't know if that is an issue? 

 

Ron

1 Accepted Solution

Accepted Solutions

You can use the command ip domain timeout to tweak timeout response lookup which 3s by default.
If your isp is down, you won't be able to resolve any name so you can use a eem to remove the forwarders for external lookup and keep only internal (hosts configured in the router)

Thanks
Francesco
PS: Please don't forget to rate and select as validated answer if this answered your question

View solution in original post

9 Replies 9

Francesco Molino
VIP Alumni
VIP Alumni
Hi

You want to setup your router as DNS server or client?

Thanks
Francesco
PS: Please don't forget to rate and select as validated answer if this answered your question

well, as a server, so it can resolve local addresses and forward requests that are not local.

 

it is working for now,  I just "hard coded" the ISP's name-servers in the router's dns

Oh thats great thanks for the update.

Please do not hesitate to click the STAR button if you are satisfied with my answer.

well,  what I would wanr ideally,  is that since the WAN interface gets the name servers automatically,  the dns service can use them too.

 

But yes it looks like it is starting to work

Great to know it works.

Thanks
Francesco
PS: Please don't forget to rate and select as validated answer if this answered your question

Yup,

 

the DNS part works, one thing I would like to improve is that when the "outgoing connection" with the ISP is down, the DNS server would not time ot, or time out faster. Because it seems that even for local lookups the dns server still wants to talk to a "domain server" first?

 

Ron

You can use the command ip domain timeout to tweak timeout response lookup which 3s by default.
If your isp is down, you won't be able to resolve any name so you can use a eem to remove the forwarders for external lookup and keep only internal (hosts configured in the router)

Thanks
Francesco
PS: Please don't forget to rate and select as validated answer if this answered your question

it's not a real big deal,  when it happens it is annoying.

 

The DNS part is working,  the stubborn issue I have now is with DHCP,  different thread.

 

thanks!

 

Ron

Review Cisco Networking products for a $25 gift card