CUCM 12.5 DHCP TIME OUT

[MoheyElbaz]

Hello,

i hope all are fine,

I have issue with Cisco Call Manager 12.5 

I have CMCM 12.5 + 2960 Switch + 7861 IP Phone + Mikrotik Router

I connected all together using VLAN 105 with 2 access ports and one trunk port for router.

I enabled the DHCP service  on CUCM.

When trying to get IP from CMCM the phone can't get IP with DHCP TIME OUT message.

[Nithin Eluvathingal]

From Cisco press book, phone boot up process.

1. The Cisco IP Phone connects to an Ethernet switchport. If the IP phone and switch support PoE, the IP phone receives power through either Cisco-proprietary PoE or 802.3af PoE.
2. As the Cisco IP Phone powers on, the Cisco switch delivers voice VLAN information to the IP phone using CDP as a delivery mechanism. The Cisco IP Phone now knows what VLAN it should use.>>> you haven’t configured voice vlan on switch port. Can you add that..
3. The Cisco IP Phone sends a DHCP request asking for an IP address on its voice VLAN.

[Roger Kallberg]

The phone gets the configuration for VLAN from the switch port it is connected to and TFTP from the DHCP scope when it gets an IP. For TFTP server assignment it’s option 150 that is used in the scope.

[Nithin Eluvathingal · Accepted solution]

Example switch configuration took fro my lab.

TO exclude the address from 1-100 i used DHCP exclude command.

ip dhcp excluded-address 10.60.56.1 10.60.56.100

ip dhcp pool Voice

 network 10.60.51.0 255.255.255.0

 default-router 10.60.51.1 

 option 150 ip 10.60.51.10 

[Roger Kallberg]

As I wrote, setup something else than CM as your DHCP server. Anything else will be better than CM as this. There are many posts in the forum about issues with CM as the DHCP server.

[Sadav Ansari]

Check your primary router address as Nithin mentioned.