Redirect syslog from busybox system to Ubuntu

Busybox syslogd uses '/etc/syslog.conf' as the configuration file. From this configuration file, can configure syslogd redirect the log messages to remote host.

- Settings of embedded system

  Check '/etc/syslog.conf' file for the configuration:

  * Make sure the 'remote' is included in variable 'DESTINATION'.

  * Make sure the variable 'REMOTE' is defined and put the right IP address of the remote syslog server

  example:

     DESTINATION="remote"
     REMOTE=<ip-of-remote-host>:514

  Restart the syslogd daemon after configuration.

- Settings of Ubuntu

  Note: assuming 'rsyslog' is used as the syslog server.

  Check '/etc/rsyslog.conf' file for the configuration:

  * Make sure rsyslog accepts remote syslog message via UDP and TCP by uncommenting out below lines:

   $ModLoad imudp
   $UDPServerRun 514

   $ModLoad imtcp
   $TCPServerRun 514

  Restart 'rsyslog' on Ubuntu after configuration. Now Ubuntu should be able to accept syslog message from target system.

- Customize the syslog on Ubuntu

1. Use simple log format

  By default, the syslog message on Ubuntu includes timing, host, and application name as prefix. Sometimes it's annoying. Customize to use simple format without these message:

  Change '/etc/rsyslog.conf' file to add a new line like this to define a new format:

   $template SimpleFormat,"%msg:::drop-last-lf%\n"

  Now you can change '/etc/rsyslog/50-default.conf' to use this format.

2. Use separate log file for particular application or host

   You may want to use separate log file for your own application, or for message from particular host. This can be done by adding configure to '/etc/rsyslog/50-default.conf' like this:

      if $programname == 'controller' then /var/log/controller.log;SimpleFormat

      if $HOSTNAME != 'localhost' then /var/log/board.log;SimpleFormat

   The first line makes the rsyslog daemon to use separate file '/var/log/controller.log' for all messages from application named 'controller' using the simple format defined above.

   The second line makes the rsyslog daemon to use separate file '/var/log/board.log' for all message coming from remote machines using the simple format defined above.