UDP Server Impl fails silently

[atduarte]

If for some reason the Syslog Server is not able to start, for example by missing permissions on address binding, there's no way to detect it, since the UDP implementation "swallows" the exception.

See https://github.com/graylog-labs/syslog4j-graylog2/blob/master/src/main/java/org/graylog2/syslog4j/server/impl/net/udp/UDPNetSyslogServer.java#L66.

Is there a reason behind this design choice?

[joschi]

@atduarte This is a relict from the original source code.

We're only using some parts of syslog4j in Graylog and the server implementations are not part of that and we have no interest in fixing issues in these parts ourselves.

If you intend to use the syslog4j server implementations, I recommend switching to another fork of syslog4j, e. g. https://github.com/NessComputing/syslog4j

This being said, feel free to provide a pull request to fix this issue.