Latest revision as of 06:04, 29 October 2023

syslog

Transport:	UDP
Portnumber:	514
RFC:	RFC 3164 RFC 3195

Syslog is a method for delivering log information from a sender to a receiver, typically across and IP network. The term syslog can be used to describe the protocol that is used to transfer messages, the application to send or receive the messages as well as the logs messages themselves.

The syslog protocol and message format are defined in RFC 3164.
RFC 3195 defines reliable delivery of syslog over UDP.
There is also a draft RFC - exprires october 1. 2009 Signed syslog Messages to standardize security in syslog messages.
Wikipedia syslog

Facility values

Syslog facility values
Code	Name	RFC 3164 facility	FreeBSD facility
0	kern	Kernel messages	Kernel messages
1	user	User-level messages	User-level messages
2	mail	Mail messages	Mail system
3	daemon	System daemons	System Daemons
4	auth	Security and Authorisation	Security and Authorisation
5	syslog	Messages generated by syslogd	Messages generated by syslogd
6	lpr	Line Printer subsystem	Line Printer subsystem
7	news	Network News subsystem	Network News subsystem
8	uucp	UUCP subsystem	UUCP subsystem
9	cron	Clock daemon	Clock daemon
10	authpriv	Security and Authorisation	Security and Authorisation
11	ftp	FTP daemon	FTP daemon
12	ntp	Network Time Protocol	Network Time Protocol
13	-	Log audit	-
14	-	Log alert	-
15	-	Clock daemon	Kernel messages
16	local0	Local use 0	Local use 0
17	local1	Local use 1	Local use 1
18	local2	Local use 2	Local use 2
19	local3	Local use 3	Local use 3
20	local4	Local use 4	Local use 4
21	local5	Local use 5	Local use 5
22	local6	Local use 6	Local use 6
23	local7	Local use 7	Local use 7

Priority values

Syslog priority values
Priority	Name
None	No priority
0	Emerg (Emergency)
1	Alert
2	Crit (Critical)
3	Err (Error)
error	Same as 3 err
4	Warn (Warning)
warn	Same as 4 warn
5	Notice
6	Info
7	Debug

Linux

It is possible to monitor output from a syslog identifier. In the example below syslog from the sshd daemon are logged tostdout

root@h5:/etc/sshguard# journalctl -afb -p info -n1 -t sshd -o cat
Connection reset by 198.235.24.119 port 58836 [preauth]
pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=127.0.0.1  user=root
Failed password for root from 127.0.0.1 port 45768 ssh2
Failed password for root from 127.0.0.1 port 45768 ssh2
Failed password for root from 127.0.0.1 port 45768 ssh2
Connection closed by authenticating user root 127.0.0.1 port 45768 [preauth]
^C

Links

Security

There is also a draft RFC - exprires october 1. 2009 Signed syslog Messages to standardize security in syslog messages.
RFC 3227 - Guidelines for Evidence Collection and Archiving[[Category:Fejlfinding]

@@ Line 96: / Line 96: @@
 |-
 |}
+=Linux=
+It is possible to monitor output from a syslog identifier. In the example below syslog from the ''sshd'' daemon are logged to'''stdout'''
+<source lang=bash>
+root@h5:/etc/sshguard# journalctl -afb -p info -n1 -t sshd -o cat
+Connection reset by 198.235.24.119 port 58836 [preauth]
+pam_unix(sshd:auth): authentication failure; logname= uid=0 euid=0 tty=ssh ruser= rhost=127.0.0.1  user=root
+Failed password for root from 127.0.0.1 port 45768 ssh2
+Failed password for root from 127.0.0.1 port 45768 ssh2
+Failed password for root from 127.0.0.1 port 45768 ssh2
+Connection closed by authenticating user root 127.0.0.1 port 45768 [preauth]
+^C
+</source>
 = Links =
@@ Line 101: / Line 114: @@
 *[http://www.syslog.org/syslog/rfc3164.txt RFC 3164 - The BSD syslog protocol]
 *[http://www.syslog.org/syslog/rfc3195.txt  RFC 3195 - Reliable Delivery for syslog using [[UDP]]]
 = Security =
 *There is also a draft RFC - exprires october 1. 2009 [http://www.ietf.org/internet-drafts/draft-ietf-syslog-sign-25.txt Signed syslog Messages] to standardize security in syslog messages.

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