ISDN T1 E1 Troubleshooting TEI_ASSIGNED
ISDN Status as TEI_ASSIGNED meaning
Which indicates that the PRI does not exchange Layer 2 frames with the Telco switch. Use the show controller e1 x command to first check the controller t1 circuit, and verify whether it is error free before troubleshooting ISDN Layer 2 problem with the debug isdn q921 command.
Symptoms :- ISDN layer 1 is active and Layer 2 going up and down with error “TEI_ASSIGNED”
There could be following missing command under signaling interface at Telco end if they are using Cisco Gateway.
isdn protocol-emulate network
interface Serial0/0/0:15
no ip address
encapsulation hdlc
isdn switch-type primary-net5
isdn protocol-emulate network
isdn incoming-voice voice
no cdp enable
Cisco trouble shooting guides
E1 Troubleshooting Troubleshooting flowchart E1 Troubleshooting Flow chart T1