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Appender::Socket(3) User Contributed Perl Documentation Appender::Socket(3)


Log::Log4perl::Appender::Socket - Log to a socket


    use Log::Log4perl::Appender::Socket;
    my $appender = Log::Log4perl::Appender::Socket->new(
      PeerAddr => "",
      PeerPort => 1234,
    $appender->log(message => "Log me\n");


This is a simple appender for writing to a socket. It relies on IO::Socket::INET and offers all parameters this module offers.

Upon destruction of the object, pending messages will be flushed and the socket will be closed.

If the appender cannot contact the server during the initialization phase (while running the constructor "new"), it will die().

If the appender fails to log a message because the socket's send() method fails (most likely because the server went down), it will try to reconnect once. If it succeeds, the message will be sent. If the reconnect fails, a warning is sent to STDERR and the log() method returns, discarding the message.

If the option "silent_recovery" is given to the constructor and set to a true value, the behaviour is different: If the socket connection can't be established at initialization time, a single warning is issued. Every log attempt will then try to establish the connection and discard the message silently if it fails. If you don't even want the warning, set the "no_warning" option to a true value.

Connecting at initialization time may not be the best option when running under Apache1 Apache2/prefork, because the parent process creates the socket and the connections are shared among the forked children--all the children writing to the same socket could intermingle messages. So instead of that, you can use "defer_connection" which will put off making the connection until the first log message is sent.


Write a server quickly using the IO::Socket::INET module:

    use IO::Socket::INET;
    my $sock = IO::Socket::INET->new(
        Listen    => 5,
        LocalAddr => 'localhost',
        LocalPort => 12345,
        Proto     => 'tcp');
    while(my $client = $sock->accept()) {
        print "Client connected\n";
        while(<$client>) {
            print "$_\n";

Start it and then run the following script as a client:

    use Log::Log4perl qw(:easy);
    my $conf = q{
        log4perl.category                  = WARN, Socket
        log4perl.appender.Socket           = Log::Log4perl::Appender::Socket
        log4perl.appender.Socket.PeerAddr  = localhost
        log4perl.appender.Socket.PeerPort  = 12345
        log4perl.appender.Socket.layout    = SimpleLayout
    for(1..10) {


Copyright 2002-2013 by Mike Schilli <> and Kevin Goess <>.

This library is free software; you can redistribute it and/or modify it under the same terms as Perl itself.


Please contribute patches to the project on Github:

Send bug reports or requests for enhancements to the authors via our

MAILING LIST (questions, bug reports, suggestions/patches):

Authors (please contact them via the list above, not directly): Mike Schilli <>, Kevin Goess <>

Contributors (in alphabetical order): Ateeq Altaf, Cory Bennett, Jens Berthold, Jeremy Bopp, Hutton Davidson, Chris R. Donnelly, Matisse Enzer, Hugh Esco, Anthony Foiani, James FitzGibbon, Carl Franks, Dennis Gregorovic, Andy Grundman, Paul Harrington, Alexander Hartmaier David Hull, Robert Jacobson, Jason Kohles, Jeff Macdonald, Markus Peter, Brett Rann, Peter Rabbitson, Erik Selberg, Aaron Straup Cope, Lars Thegler, David Viner, Mac Yang.

2022-10-22 perl v5.40.0