System information

1-22 AR Series Router Reference Manual
Software Release 2.0.1
C613-03018-00 REV A
Monitoring and Fault Diagnosis
Event Logging
The router responds to certain significant events by generating an event log
message. Each router maintains a local event log of the most recent log
messages. To view the log, use the command:
SHOW LOG
The logging facility provides a powerful, flexible and easily configurable tool
for monitoring network activity and selecting and displaying the results. User-
defined output definitions can filter, prioritise and output log messages to
RAM, NVS, an asynchronous port, another router, a syslog server or an email
address. See Chapter 23, Logging Facility for a detailed description of the logging
facility.
Restarts
Some changes to configuration parameters require the router to be restarted for
the changes to take affect. The router is restarted with the command:
RESTART {REBOOT|ROUTER} [CONFIG={filename|NONE}]
If the router encounters a fatal error condition from which it can not recover, it
automatically performs a restart. The reason for the restart may be determined
by examining the router’s exception list, with the command:
SHOW EXCEPTION
The conditions that the router encountered when it last restarted, such as the
amount of RAM and the state of the battery-backed RAM, can be viewed with
the command:
SHOW STARTUP
A complete snapshot of the state of the router prior to the last fatal condition
can be displayed with the command:
SHOW DEBUG
CPU Utilisation
The CPU utilisation over the last second, ten seconds, one minute or since the
router last restarted can be displayed with the command:
SHOW CPU
Memory
The state of the router’s buffer pool can be examined with the command:
SHOW BUFFER
If the pool of free buffers drops below a critical threshold, the router
progressively disables processes, resulting in a loss of functionality. This
problem can potentially arise when a fast source sends enormous amounts of
data to a slow destination or down a slow link. However, the cause is more