How to view logs on JunOS

In this article, I will give examples of viewing logs on the Juniper MX204.

View user login log on Juniper:

show log user
show log user admin

View all available log files:

show log

View system messages:

show log messages

An example of filtering records by specific criteria:

show log messages | last 30
show log messages | match "Dec 15 12:030"
show log messages | match "Error"
show log messages | match "Error" | last 10
show log messages | match "(pattern1|pattern2)"

Some logs can be written to separate files, this is configured in the “system processes” section, for example DHCP logs, an example of viewing:

show log dhcp_logfile | last 70

I will write about setting up logs in separate articles.

See also my articles:
Juniper MX204 setup
Configuring SNMP traceoptions
Configuring Juniper Devices

Leave a comment

Leave a Reply