There are many times it happens that your Cisco IP Phone does not register with the call manager server.
In a normal phone bootup process, it should go through the steps gives here.
In a normal phone bootup process, it should go through the steps gives here.
When the phone does not go through its normal startup process
- Check the network port is working:
- Change a network cable with the working cable.
- Try connecting phone to the port that is known to be working fine.
- Check the phone is receiving power:
- Check that the electric outlet is working.
- If the phone is getting power via POE check the inline power port on the switch
Verify TFTP server settings
Cisco IP phone user TFTP server IP address to get the configuration file from where it gets the IP address of CUCM to register with the server.
If you are giving static IP addresses to phone then you need to add this IP address to TFTP settings.
When you are using DHCP, the phone gets an IP address from DHCP server. Check the IP address configured in Option 150.
When using DNS Check the hostname in DHCP Option 66.
Check if Cisco Unified CallManager and TFTP services are Active
Navigate to Cisco Unified Serviceability and follow the path Tools > Control Center > Feature Services and check the services Cisco Unified CallManager and TFTP are active and running.