Technical Documentation

JUNOS Software Default System Log Settings

Table 1 summarizes the default system log settings that apply to all routers that run the JUNOS Software, and specifies which statement to include in the configuration to override the default value.

Table 1: Default System Logging Settings



Overriding Statement


Alternative facility for message forwarded to a remote machine

For change-log: local6

For conflict-log: local5

For dfc: local1

For firewall: local3

For interactive-commands: local7

For pfe: local4

[edit system syslog]host hostname {facility-override facility;}

Changing the Alternative Facility Name for Remote System Log Messages

Format of messages logged to a file

Standard JUNOS format, based on UNIX format

[edit system syslog]file filename {structured-data;}

Logging Messages in Structured-Data Format

Maximum number of files in the archived set


[edit system syslog]archive {files number;}file filename {archive {files number;}}

Specifying Log File Size, Number, and Archiving Properties

Maximum size of the log file

J Series: 128 kilobytes (KB)

M Series, MX Series, and T Series: 1 megabyte (MB)

TX Matrix: 10 MB

[edit system syslog]archive {size size;}file filename {archive {size size;}}

Specifying Log File Size, Number, and Archiving Properties

Timestamp format

Month, date, hour, minute, second

For example: Aug 21 12:36:30

[edit system syslog]time-format format;

Including the Year or Millisecond in Timestamps

Users who can read log files

root user and users with the JUNOS maintenance permission

[edit system syslog]archive {world-readable;}file filename {archive {world-readable;}}

Specifying Log File Size, Number, and Archiving Properties

Published: 2010-04-26