3Com 3C10402B, Administrator'S Manual

Page: 391 / 582

Syslog Message Components 391
By default, Syslog starts up at every reboot with only error messages
checked in as default and sends the log messages to the enabled Syslog
servers. You can implement up to three Syslog servers.
For information about how to configure Syslog, see the online Help.
Syslog Message
Components
This section describes how to format Syslog messages for transport.
The full format of a Syslog message has three discrete components:
■
PRI (Priority) Message Component
■
Header Component
■
MSG Component
The total length of the packet must be 1024 bytes or less. There is no
minimum length for the Syslog message, although it is a waste of
resources to send Syslog packets with no contents. The contents of a
message are at the discretion of its creator.
PRI (Priority) Message
Component
The PRI portion of a Syslog message must have the following
characteristics:
■
Three, four, or five characters
■
Be bound with angle brackets as the first and last characters.
The PRI portion starts with a leading less-than (<) character, followed
by a number, which is followed by a greater-than (>) character.
The less-than character is defined as the Augmented Backus-Naur
Form (ABNF) %60, and the greater-than character has an ABNF value
of %62. The number contained within these angle brackets is known
as the Priority value, and represents both the Facility and Severity, as
described in the section
“Facilities Codes and Severity Message
Codes” .
The Priority value consists of one, two, or three decimal integers
(ABNF DIGITS) using values of %d48 (for 0) through %d57 (for 9).
Facilities Codes and Severity Message Codes
The Facilities codes and Severity Message codes are numerically coded
with decimal values.