Attach Procedure Troubleshooting Highlighted

This article will introduce how to troubleshoot the attach procedure for eLTE5.0 (3GPP) solution.

Version Mapping

Procedure

eUE cannot attach to eLTE network. To analyze the problem, perform the following operations:

1.     Login to eAPP, check alarms.

2.     Login to vUSN, check alarms.

3.     On vUSN, check whether S11 interface is up. Try to ping from USN_S11 IP to UGW_S11 IP.

4.     Go to USN_VFNC, run LST HAPNTPL and check access point name:

5.     Go to USN_VNFC, run LST HPLMN and check operator name. It must be consistent with the result of the previous command.

6.     On USN_VNFC, run LST IPV4DNSH and check whether host name includes access point name:

7.     Login to vUGW, go to UGW_UGW, run LST APNDNSand check whether APN is configured correctly:

(NOTE: Primary IPv4 DNS is not mandatory and has no impact on attach procedure.)

8.     Go to UGW_UGW, run LST APN and check whether APN is configured correctly:

9.     Go to UGW_UGW, run LST POOL and check whether a pool is configured for terminals:

10.   Go to UGW_UGW, run LST SECTION: POOLNAME="pool1"; and check whether a section is configured for pool1. IP address defines terminal’s IP block:

11.   Go to UGW_UGW, run LST POOLBINDAPN; and check whether pool bound to A:

12.   Login to eUDC, go to Registration > Card Management, find eUE by IMSI click Edit, check whether Access Point Name is correct:

13.   Turn on eUE and check whether configurations are correct on eUE, go to Settings > More > Mobile networks

a.     Check Server Settings. IP should be set to eUDC service IP. Port should be 8013

b.     Check Access Point Names. The expected value is empty.

14.   Go to vUSN and start a User Trace task.

Scenario 1: If KI value is set wrong on eUDC, the following error would be displayed in User Trace.

Delete Card from eUDC and add again with correct KI value. Usually KI value is filled automatically when IMSI has been generated. No need to change it.

Scenario 2: If APN on eUE and APN on eCore does not match, the following error would be displayed:

Go to Step13 and check if there is an APN defined on eUE. If there is no, follow previous steps to check whether vUSN and vUGW APNs are matched.

Author Notes

eLTE attach procedure troubleshooting has been described above. It has been written at last but when you face the issue, the first thing to do is checking traces. Also, consider below information to attach an eUE to eLTE network:

Ø eUE should be added as a terminal, card, and user in eUDC.

Ø eUDC must be synchronized with vUSN by its mediation file.

Ø Authentication key on eUDC is the same with KI value on vUSN.

Ø S11, S5/S8 interfaces should be up, even it looks like it is not important

Ø There are two different APNs defined. One is in vUSN which is used in IPV4DNSH and DNSN management objects. Other one is in vUGW which should be matching with apn defined on eUDC.

Do not mix them!

Ø In vUSN it is also possible to add cards with details as HUSIM. But it has a bad impact on the system and attaches fails. If you don’t need it, don’t add cards with ADD HUSIM command. Let eUDC transmit card details to vUSN through PGW-SGW.

Ø eUDC must be pinging eUE’s IP block. If there is no ping, check routes on the switch.