Cisco Emergency Responder (Cisco ER) obtains a list of registered phones from Cisco CallManager and tries to locate all phones. If Cisco ER cannot locate a phone, it places the phone in the default Emergency Response Location (ERL) and puts it in a list of unlocated phones.
These are some explanations that can prevent Cisco ER from locating a phone:
If more than one switch port reports the phone as a Cisco Discovery Protocol (Cisco DP) neighbor, then the phone is placed in unlocated phones. This condition is corrected in the next phone tracking when only one switch port reports this phone as its Cisco DP neighbor.
The phone is connected to a hub, which is connected to a supported switch port, but it does not support Cisco DP. Cisco ER can consistently discover Cisco DP-enabled phones attached to hubs (which are attached to supported switch ports), but cannot always track non-Cisco DP phones attached in this manner. For non-Cisco DP phones, ensure the phones are attached directly to supported switch ports.
The switch to which the phone is connected is currently unreachable, for example, it does not respond to Simple Network Management Protocol (SNMP) queries. These could be among the reasons:
There is a network outage preventing communication between the Cisco ER server and the switch. Locate and resolve the network outage problem.
Unreachable switches are not retried until Cisco ER runs the next full switch-port and phone update process, unless you run it against the individual switch as described in the following list.
The phone has moved to a switch served by a different Cisco ER group. If this is the case, the Cisco ER group name is shown for the phone in the unlocated phones list. If the phone is not located in the next incremental phone tracking process after it is moved, the phone remains unlocated in any Cisco ER group until a full switch-port and phone update process is run.