How do I configure rsyslog to send logs from a specific program to a remote syslog server?

  • I have a program which outputs to syslog with a given tag/program name. I'd like to be able to filter syslog traffic from that program and send it to a remote syslog server, leaving all other syslog traffic local.

    I can send all traffic to the remote server with

    *.* @remote_server
    

    How do I filter it?

  • oblivian

    oblivian Correct answer

    8 years ago

    Rsyslog config files are located in: /etc/rsyslog.d/*.conf

    Rsyslog reads the conf files sequentially, so it is important that you name your config file so that the specific config is loaded before anything else happens. So, name your file starting with leading zero's, i.e. 00-my-file.conf. It's better to create a new file so that updates and so on doesn't overwrite your local config.

    Example:

    if $programname == 'programname' and $msg contains 'a text string' and $syslogseverity <= '6' then /var/log/custom/bind.log
    

    Or if you just want to discard certain entries:

    if $programname == 'programname' then ~
    

    In your case: (UDP)

    if $programname == 'programname' then @remote.syslog.server
    & ~
    

    Or (TCP)

    if $programname == 'programname' then @@remote.syslog.server
    & ~
    

    The & ~ means to stop processing matching (previous line only!) entries further.

    Some more general info:

    Also, always make sure filters are on the same line:

    # Example: Log mail server control messages to mail-queue.log
    if $hostname == 'titus'\
    and $programname == 'smtp.queue.'\
    and $syslogseverity <= '6' then /var/log/titus/mail-queue.log
    & ~
    

    Usefull filters:

    $hostname
    $programname
    $msg
    $syslogseverity
    

    Operators:

    == (equals)
    contains
    and
    or
    

    More info: http://wiki.rsyslog.com/index.php/Configuration_Samples

    can we fix the broken link?

  • We can also try this. It's working fine for me.

    $template Incoming-logs,"/var/log/testing_docker/%PROGRAMNAME%.log"
    if $programname startswith 'docker' then -?Incoming-logs
    

    NOTE: here testing_docker folder ownership should be given to the syslog user. Follow the below command to set permissions.

    chown syslog:syslog testing_docker
    

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Content dated before 6/26/2020 9:53 AM