RFC 3164 (rfc3164) - Page 1 of 29
The BSD Syslog Protocol
Alternative Format: Original Text Document
Network Working Group C. Lonvick
Request for Comments: 3164 Cisco Systems
Category: Informational August 2001
The BSD syslog Protocol
Status of this Memo
This memo provides information for the Internet community. It does
not specify an Internet standard of any kind. Distribution of this
memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (2001). All Rights Reserved.
Abstract
This document describes the observed behavior of the syslog protocol.
This protocol has been used for the transmission of event
notification messages across networks for many years. While this
protocol was originally developed on the University of California
Berkeley Software Distribution (BSD) TCP/IP system implementations,
its value to operations and management has led it to be ported to
many other operating systems as well as being embedded into many
other networked devices.
Table of Contents
1. Introduction....................................................2
1.1 Events and Generated Messages..................................3
1.2 Operations of the Message Receivers............................5
2. Transport Layer Protocol........................................5
3. Definitions and Architecture....................................5
4. Packet Format and Contents......................................7
4.1 syslog Message Parts...........................................8
4.1.1 PRI Part.....................................................8
4.1.2 HEADER Part of a syslog Packet..............................10
4.1.3 MSG Part of a syslog Packet.................................11
4.2 Original syslog Packets Generated by a Device.................12
4.3 Relayed syslog Packets........................................12
4.3.1 Valid PRI and TIMESTAMP.....................................13
4.3.2 Valid PRI but no TIMESTAMP or invalid TIMESTAMP.............13
4.3.3 No PRI or Unidentifiable PRI................................14
5. Conventions....................................................14
5.1 Dates and Times...............................................15
5.2 Domain Name and Address.......................................15
Lonvick Informational
