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Cisco Call Manager DHCP Settings

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I am running Cisco Call Manager version 7.1.5 and cannot find where to change my DNS servers so my phones get the correct information.  I have changed the DNS server addresses everywhere I can find in the Call Manager software, but my phones continue to get the wrong address?  Can someone please tell me how to get in and change that?
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System > DHCP > Server or Subnet. The DNS in the Subnet has precedence over the one in the Server config.

If this doesn´t populate on your IP phone correctly make sure it is taking the settings from the right DHCP offerer.
Info TechIT Department

Author

Commented:
Ah. So I just checked both call managers for this information.  Niether Call manager says it has a DHCP server running.  I'm wondering if my router is handling DHCP for my phones now?  Could that be?
No idea. Open your browser pointing to the IP of one of the phones (if it is configured with the Web enabled setting from the CM config page) and you will see from which device it took the settings
Top Expert 2010
Commented:
The router can be the DHCP if configured properly.  

The usual Cisco IOS router DHCP would look something like this:
ip dhcp pool VOIPPool
   network 10.1.1.0 255.255.255.0
   default-router 10.1.1.1
   option 150 ip 10.1.1.10 10.1.1.11   <- option 150 assigns the TFTP addresses for call manager
   dns-server 10.1.1.15 10.1.1.16      <- Dns server addresses assigned via DHCP
   domain-name mydomain.com          <- Local domain name
   lease 2    <- Length of lease time
!

Just check your phone's DHCP server as willywilbur said
Info TechIT Department

Author

Commented:
I do remember when we upgraded to Cisco Call Manager 7.1.5 that the guy said the router is now the DHCP server for all of our phones.  Does anyone know the command line to change the DNS servers for the DHCP config? It is a Cisco Voice router.
Mike gave it to you already

ip dhcp pool <pool name>
      dns-server <ip address 1> <ip address 2>
Info TechIT Department

Author

Commented:
Ah, OK. So I'm in the router, I found the ip dhcp pool IPPHONES, I can see the wrong DNS server address in there.  I went in and got into the config.  Typed exactly this "ip dhcp pool IPPHONES" then it brought me into the dhcp config.  then I typed exactly this "dns-server 192.168.1.3 192.168.1.56" hit Cntl Z to save.  Then did a sh config again and it didn't change.  What did I miss?
Info TechIT Department

Author

Commented:
I got it.  Just had to do a "write".

Thanks!!!
Top Expert 2010

Commented:
Glad its working.   Anything else related to this then?