Logging to Syslog

AMPS can also log messages to the host’s syslog mechanism. To use the syslog logging target, use a Protocol of syslog in the logging target definition.

The host’s syslog mechanism allows a logger to specify an identifier on the message. This identifier is set through the Ident property and defaults to the AMPS instance name (see Instance-Level Configuration for details on configuring the AMPS instance name).

The syslog logging target can be further configured by setting the Options parameter to a comma-delimited list of syslog flags. The recognized syslog flags are:

Level	Description
LOG_CONS	Write directly to system console if there is an error while sending to system logger.
LOG_NDELAY	Open the connection immediately (normally, the connection is opened when the first message is logged).
LOG_NOWAIT	No effect on Linux platforms.
LOG_ODELAY	The converse of LOG_NDELAY; opening of the connection is delayed until syslog() is called. (This is the default, and need not be specified.)
LOG_PERROR	Print to standard error as well.
LOG_PID	Include PID with each message.

AMPS already includes the process identifier (PID) with every message it logs, however, it is a good practice to set the LOG_PID flag so that downstream syslog analysis tools will find the PID where they expect it.

The Facility parameter can be used to set the syslog “facility”. Valid options are: LOG_USER (the default), LOG_LOCAL0, LOG_LOCAL1, LOG_LOCAL2, LOG_LOCAL3, LOG_LOCAL4, LOG_LOCAL5, LOG_LOCAL6, or LOG_LOCAL7.

Finally, AMPS and the syslog do not have a perfect mapping between their respective log severity levels. AMPS uses the following table to convert the AMPS log level into one appropriate for the syslog:

AMPS Severity	Syslog Severity
none	LOG_DEBUG
developer	LOG_DEBUG
trace	LOG_DEBUG
stats	LOG_INFO
info	LOG_INFO
warning	LOG_WARNING
error	LOG_ERR
critical	LOG_CRIT
emergency	LOG_EMERG