Description: This document describes the necessary steps to determine the cause of a LANCOM router's unexpected system reboot.
Procedure: Causes of a system restart, apart from manual rebooting or a problem with the power supply, may be an internal problem detected by the router. If this is the case, the router will restore its operating state by restarting.
After rebooting, you can determine the cause by accessing the device's boot log.
Recording the bootlog via the CLI: Start a SSH session on the device and enter the command
show bootlog:
The boot log in this screen shot shows that no errors have occurred since the last boot.
A manual system reboot would be listed here as "System boot after manual boot request".
After an error is detected, the output may include an "LCOS watchdog", an error message from the operating system. For example:
9/12/2006 12:54:50 LCOS-Watchdog
Task name = CT Type=Com-Handle not released Code=0x00000013 Task=0x005caac0 Nest=0x00000000 Recording the bootlog via the LANtracer: LANCOM Systems recommends using LANconfig as of version 10.20 RU3 (download current version) since additional information for error analysis has been implemented.
1. Open the configuration of the LANCOM router or access point and switch to the menu item
Management -> Admin -> Ports.
2. Make sure that the protocol
TELNET-SSL is active and the
Port is set to
992.
3. Switch to the menu item
Management -> Admin -> Access settings-> Access rights and change the
access rights for the protocol
TELNET-SSL if necessary.
Info: - Please also see the document
Securing the remote access to LANCOM routers from the WAN: 
4. Select the router in LANconfig, perform a rightclick and choose
Create Trace output in the pop-up menu.
5. In the trace module click the
green play symbol. The bootlog is recorded automatically.
6. Click the
red stop symbol to stop the trace.
7. Click on the
disk symbol to save the trace (
*lct file) as well as the support configuration (
*spf file).
Info: - The support configuration is the device configuration where the passwords have been cleared.
Further action: The watchdog output is usually cryptic and requires analysis by the experts at LANCOM Systems. For error analysis, please contact
LANCOM Support.
For diagnosis we require the full-length boot log as a text file and also the device's configuration file.
Please send a text file containing the boot log or the trace file together with the device configuration file to LANCOM Systems Support.
