Case16: eNB reboot due to GPS Clock syn Failure

Equipment: H2000

Version: Firmware-V1.6.7 Trunk-59269

1. Issue Description

Client reports all the UE connetivity was not stable, keep connecting and disconnected. And throughput was also low.

2. Troubleshooting procedure

Configuration and log analysis:

From the log and configuration, the clock syn mode was changed from GPS to freedom since 3 rd , Dec after power off and on.It’s a known issue when GPS clock syn failure and change to freedom or sniffer.

2023-12-03 11:35:14.493 [SCM] ---------- eHNB power on (cold boot, harddog enabled, SyncMode:GNSS, firmware-version V1.6.7, platform-version FSM9955.PP.3.0.9(r9.3),FSM9955.DV.3.0.9(r9.3), build-version trunk-r59269, build-time 2022-12-15T03:21:23Z) ----------

2023-12-03 11:40:37.736 [SON] Alarm Report, id: 0x16020106 file: src/son_timer.c line: 1645 detail: SyncMode = 0, report sync error alarm

2023-12-03 11:40:38.257 [SON] Alarm Report, id: 0x16010400 file: src/son_timer.c line: 1696 detail: SON: SonRecvInitialSyncTimeoutInd, sync failure, syncmode change to freerun and try again

Summary:

Power off and on reboot caused the GPS delayed to lock. Clock synmode change and synchronize failure which caused eNB soft reboot. And UE disconnect and connect again.

3. Solution

Temporary action: Change the clock mode from freedom to GPS and restart. Permanent solution: Upgrade the fimware version from V1.6.7 to V1.6.8 or above asap.