The syslog protocol was first defined as part of the UNIX operating system to log messages within the OS. Syslogs allow a computer or device to deliver messages to another computer. Syslog messages have a particular format that associates a facility, and a severity or priority with a message.
The facility code allows syslog to group messages from different sources and take action based on this facility or group. The facilities are described in Table 8-7 and the priorities supported are described in Table 8-8.
|local0-7||Reserved for locally defined messages|
|Lpr||Line printer system|
|News||USENET news ...|