One ip Phone cannot get ip address from CUCM

[eigrpy]

Hi Two ip phones are at the same subnet work. One phone can get ip address from CUCM, but another phone which used to get ip address cannot get ip address now even after setting to factory configuration. Anyone give some suggestion? Thank you.

[Mishkin · Accepted solution]

I assume that if you reset it to factory default, the dhcp is enabled, so have you checked the basic things?

First of all, that the phone is attached to a port with the correct voice vlan configuration.

If the DHCP is provided by a Cisco device, you can check that the ip is not in conflict. (#sh ip dhcp conflict).

If so, or you suspect it could be an issue with the pool I should do the following things:

#clear ip dhcp binding *
#clear arp
#clear mac-address-table
#clear ip dhcp conflict *

It happened to me before and it is a way to solve it.

Best regards.

[eigrpy]

Thank you so much for your reply. both work after adding ip helper-add. Strange that why the ip helper-add disappeared