syslog-redirector

A statically compiled tool to spawn an executable redirecting its standard out and standard error to syslog.

Static compilation is important, at least in the intended Helios/Docker use case, as we do not want to make any assumptions as to the contents of the container and the availability or location of libc. Specifically, BusyBox and Ubuntu containers have libc in different places, and I'm sure there are others.

Build

Note: Requires docker.

make

Installation

For Helios usage, it expects syslog-redirector to live in /usr/lib/helios, so copy it there. Otherwise, put it wherever you like.

Developing

Prerequisites:

• syslog listening to a port somewhere you can talk to

It includes two slightly modified files from the golang library, as they had bugs at the time with respect to reconnecting if I recall correctly. Newer versions of golang may not have this problem, and so these copied and modified files may be superfluous now, but I just haven't gotten around to looking and testing, and I know this current one works and haven't had to touch it, save for opensourcing in a great many moons.

Also, we submodule the go distribution, as we've run into issues coaxing go to create a static executable. Yes, it's supposed to just do this, but it's not doing it reliably depending on exactly which go version you had, and we wanted a reproducible build. The go we submodule is linux-amd64. If care less about the static-buildness, adjust the build command above. If you find a better solution to this, pull requests are most definitely welcome.

Use With Helios

When starting the Helios Agent, pass the --syslog-redirect-to switch with the host:port of where syslog is running on the agent machine.

Use Outside of Helios

usage: ./syslog-redirector -h syslog_host:port -n name -- executable [arg ...]
  -h="": Host port of where to connect to the syslog daemon
  -n="": Name to log as
  -t=false: use TCP instead of UDP (the default) for syslog communication
  -tee=false: also write to stdout and stderr

Example:

./syslog-redirector -h 10.0.3.1:6514 -n test-ls-thingy -- ls -l

This would run the command

ls -l

and redirect it's stdout and stderr to TCP syslog running at 10.0.3.1:6514 and the name that will show up in the syslogs is test-ls-thingy.

Normally, it uses TCP connections to syslog, but the -t switch can be used to tell it to use UDP instead.

Standard out will be logged as LOG_INFO and standard error will be logged as LOG_ERROR.