PacketIn Event

Fires whenever a system log packet is received.

Syntax

syslog.on('PacketIn', [callback])

Callback

The 'callback' is called when the 'PacketIn' event is emited.

function(e){ }

The argument 'e' has the following properties:

e.facilityCode
e.facility
e.severityCode
e.severity
e.timestamp
e.hostname
e.message
e.conforms
e.packet (buffer)
e.sourceAddress
e.sourcePort

Remarks

System log packets are composed of three main sections, each of which can be broken down into two smaller pieces.

The first section is the PRI, which contains the originating FacilityCode and SeverityCode of the Message. FacilityCode is a value from 0 to 23, with each value being a different part of the system. Facility is a string representation of FacilityCode based on the following convention:


0	Kernel messages
1	User-level messages
2	Mail system
3	System daemons
4	Security/authorization messages
5	Messages generated internally by syslogd
6	Line printer subsystem
7	Network news subsystem
8	UUCP subsystem
9	Clock daemon
10	Security/authorization messages
11	FTP daemon
12	NTP subsystem
13	Log audit
14	Log alert
15	Clock daemon
16	Local use
17	Local use
18	Local use
19	Local use
20	Local use
21	Local use
22	Local use
23	Local use

SeverityCode is a value from 0 to 7. Severity is a string representation of SeverityCode using the following convention:


0	Emergency - the system is unusable.
1	Alert - action must be taken immediately.
2	Critical - critical conditions exist.
3	Error - error conditions exist.
4	Warning - warning conditions exist.
5	Notice - normal but significant condition.
6	Informational - informative message.
7	Debug - debug-level messages.

The second section contains the Timestamp and Hostname. Timestamp is a string that should conform to the standard structure "MMM DD, HH:MM:SS". The class will search for the Timestamp and verify that it conforms. If it conforms, the class will set Hostname, otherwise, everything after the PRI will be placed in Message.

If Conforms is TRUE, then the original syslog packet conforms to the syslog RFC and Timestamp, Hostname, and Message will all have valid values. Otherwise, you should parse the contents of Packet to verify the fields manually.

SourceAddress and SourcePort are the address and port from which Packet was sent. This can be an intermediate syslog server that is simply forwarding packets from the original host.