Syslog message modifiers
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Remove imbedded date and time from Cisco messages
When a Cisco device sends a Syslog message, it adds it's own time stamp to the message. You may want to remove these extra time stamps to save space or make the logged files more readable.

This option works by looking for a particular Cisco message format. It will work with all the known Cisco date and time formats available including Cisco PIX firewall messages.


Allow messages with no priority (use default priority)

Some routers and hosts may send messages that contain no priority code in the message. In situations where this occurs you can apply a default priority to the message. Check this box and then set the default priority you want to use, from the drop down lists.


A normal Syslog message has a priority code at the start of the message text.
Example. <100>This is a test message
The priority value should be between 0 and 191 for standard Unix priority codes


Maximum message length (bytes)

This option allows you to limit the maximum message size of incoming messages. You may want to change this to a lower value than the default 4096 bytes if you are only expecting small messages.

This limit allows the program to reject oversize messages sent by hackers or errors in transmission.
Some Syslog Daemons may crash when receiving large packets, this option limits the size of the packet that the program will accept and process.

The Syslog RFC 3164 states that legal Syslog messages may not exceed 1024 bytes in length. (Not including packet headers)


Allow messages with priority > 191 (use default priority)
Each Syslog message has a priority code at the beginning of the message. Normally with Unix systems and router devices, this priority code has a value between 0 and 191. Sometimes devices send messages with a priority code higher than 191. Even though the priority value can be higher than 191, there is no standard to define priority levels or facilities above 191.

If this option is enabled, messages received with a priority higher than 191 will have their priorities set to the default priority setting.


Remove CR/LF from end of messages
Some routers or hosts send messages with a CR/LF attached to the end of the message text. This will cause the log files to be double spaced.

Check this box if you want to remove all trailing CR/LF characters from the messages.



Replace non-printable characters with <ASCII value>
Some routers or hosts may send messages that contain control characters in the message text. For example, multi-line messages will contain carriage returns and line feeds. If you enable this option, instead of trying to display control characters, the equivalent ASCII value will be displayed.

E.g. When a carriage return is received, it will be replaced with a <013> instead.