LMTP support, init scripts for Ubuntu and Debian, syslog, and much more.

debian/poolmon.default

+# Here you can specify your poolmon command line options.
+#
+#OPTIONS=""

debian/poolmon.init

+#!/bin/bash
+#
+#       /etc/rc.d/init.d/poolmon
+#
+# Starts the poolmon daemon
+#
+# description: Poolmon mailserver pool monitor
+# processname: poolmon
+# pidfile: /var/run/poolmon.pid
+
+### BEGIN INIT INFO
+# Provides: poolmon
+# Required-Start: $network dovecot
+# Required-Stop: $network
+# Default-Start: 2 3 4 5
+# Default-Stop: 0 1 6
+# Short-Description: start and stop Poolmon mailserver pool monitor
+# Description: Poolmon monitors a pool of Dovecot director mailservers
+#		and dynamically alters their state based on active health
+#		checks performed at regular intervals.
+### END INIT INFO
+
+# Source function library.
+#. /etc/init.d/functions
+. /lib/lsb/init-functions
+
+if [ -f /etc/default/poolmon -a $UID -eq 0 ]; then
+    . /etc/default/poolmon
+fi
+
+RETVAL=0
+prog="Poolmon"
+exec="/usr/sbin/poolmon"
+pidfile="/var/run/poolmon.pid"
+lockfile="/var/lock/poolmon"
+
+start() {
+	[ $UID -eq 0 ] || exit 4
+	[ -x $exec ] || exit 5
+
+	echo -n $"Starting $prog: "
+	start_daemon -p $pidfile $exec $OPTIONS
+	RETVAL=$?
+	[ $RETVAL -eq 0 ] && touch $lockfile
+	echo
+}
+
+stop() {
+	[ $UID -eq 0 ] || exit 4
+	echo -n $"Stopping $prog: "
+	killproc -p $pidfile $exec
+	RETVAL=$?
+	[ $RETVAL -eq 0 ] && rm -f $lockfile
+	echo
+}
+
+reload() {
+	[ $UID -eq 0 ] || exit 4
+	echo -n $"Reloading $prog: "
+	killproc -p $pidfile $exec -HUP
+	RETVAL=$?
+	echo
+}
+
+#
+#	See how we were called.
+#
+case "$1" in
+  start)
+	start
+	;;
+  stop)
+	stop
+	;;
+  reload)
+	reload
+	;;
+  force-reload|restart)
+ 	stop
+	sleep 1
+	start
+ 	RETVAL=$?
+	;;
+  condrestart|try-restart)
+ 	if [ -f $lockfile ]; then
+	    stop
+	    sleep 3
+	    start
+	fi
+	;;
+  status)
+	status_of_proc -p $pidfile $exec
+	RETVAL=$?
+	;;
+  *)
+	echo $"Usage: $0 {condrestart|try-restart|start|stop|restart|reload|force-reload|status}"
+	RETVAL=2
+	[ "$1" = 'usage' ] && RETVAL=0
+esac
+
+exit $RETVAL
+

debian/systemd.poolmon.default

+# Here you can specify your poolmon command line options.
+#
+[Service]
+OPTIONS=""

debian/systemd.poolmon.service

+[Unit]
+Description=Poolmon monitors a pool of Dovecot director mailservers \
+ and dynamically alters their state based on active health \
+ checks performed at regular intervals.
+After=syslog.target network.target remote-fs.target nss-lookup.target
+
+[Service]
+Type=simple
+EnvironmentFile=-/etc/default/poolmon
+WorkingDirectory=/
+ExecStart=/usr/sbin/poolmon -f $OPTIONS
+Restart=on-failure
+LimitNOFILE=10000
+
+[Install]
+WantedBy=multi-user.target
+

poolmon

@@ -26,9 +26,9 @@
 use strict;
 use Getopt::Long;
 use IO::Socket::UNIX;
-use IO::Socket::INET;
-use IO::Socket::SSL;
+use IO::Socket::IP;
 use POSIX qw(setsid strftime);
+use Sys::Syslog qw( :DEFAULT setlogsock);
 
 $SIG{'PIPE'} = 'IGNORE';
 
@@ -46,6 +46,8 @@ my $DIRECTOR = '/var/run/dovecot/director-admin';
 my $CREDFILE = '';
 my $USERNAME = '';
 my $PASSWORD = '';
+my $LMTP_FROM = '';
+my $LMTP_TO = '';
 my $WEIGHTS;
 my %WEIGHTS;
 
@@ -62,12 +64,21 @@ GetOptions('p|port=s'     => \@PORTS,
            'h|help|?'     => \&help,
            'w|weights=s'  => \&opt_weights,
            'c|credfile=s' => \&opt_credfile,
+           'lmtp-from=s'  => \$LMTP_FROM,
+           'lmtp-to=s'    => \$LMTP_TO,
     ) or help();
 
 unless (@PORTS || @SSL_PORTS){
     @PORTS = qw(110 143);
 }
 
+if (@SSL_PORTS) {
+    eval("use IO::Socket::SSL;");
+    if ($@) {
+        die "$@";
+    }
+}
+
 check_pidfile();
 unless($NOFORK){
     daemonize();
@@ -99,6 +110,7 @@ Arguments:
   -i, --interval=SECS   Scan interval in seconds (default: 30)
   -k, --lockfile=PATH   PID/lockfile location (default: /var/run/poolmon.pid)
   -l, --logfile=PATH    Log file location (default: /var/log/poolmon.log)
+                        Set to 'syslog' for writing to local syslog socket
   -p, --port=PORT       Port to check; repeat for multiple (default: 110, 143)
   -s  --ssl=PORT        Port with SSL/TLS; repeat for multiple (default: none)
                         If the port is recognized as common IMAP or POP3 port,
@@ -110,7 +122,9 @@ Arguments:
                           - Username on 1st line.
                           - Password on 2nd line.
                         (default: health checks will not attempt authentication)
-  -S, --socket=PATH     Path to Dovecot director-admin socket 
+  --lmtp-from=ADDR      Sender e-mail address for LMTP
+  --lmtp-to=ADDR        Recipient e-mail address for LMTP
+  -S, --socket=PATH     Path to Dovecot director-admin socket
                         (default: /var/run/dovecot/director-admin)
   -t, --timeout=SECS    Port health check timeout in seconds (default: 5)
   -w, --weights=PATH    Location of file containing host:weight lines
@@ -181,23 +195,35 @@ sub director_connect {
     return $sock;
 }
 
-# Scan all ports on a given host
+# Scan all ports on a given host. 1 == success. 0 == failure
 sub scan_host {
     my ($host, $weight) = @_;
     my $OK = 1;
     # Check non-SSL ports first
     foreach my $port (@PORTS){
         if (! scan_port($host, $port, 0)){
-            $OK = 0;
-            last;
+            sleep(3);
+            for (my $i=0; $i <= 3; $i++) {
+                if (! scan_port($host, $port, 0)){
+                    $OK = 0;
+                    last;
+                }
+                sleep(0.5);
+           }
         }
     }
     # Skip SSL checks if standard checks indicated failure
     return 0 unless $OK;
     foreach my $port (@SSL_PORTS){
         if (! scan_port($host, $port, 1)){
-            $OK = 0;
-            last;
+            sleep(3);
+            for (my $i=0; $i <= 3; $i++) {
+                if (! scan_port($host, $port, 1)){
+                    $OK = 0;
+                    last;
+                }
+                sleep(0.5);
+           }
         }
     }
     return $OK;
@@ -209,7 +235,7 @@ sub scan_port {
     my $host = shift || return;
     my $port = shift || return;
     my $ssl  = shift;
-    my $sock = $ssl ? IO::Socket::SSL : IO::Socket::INET;
+    my $sock = $ssl ? IO::Socket::SSL : IO::Socket::IP;
     my $prot;
     my $ret;
 
@@ -229,6 +255,8 @@ sub scan_port {
                 return scan_imap($host, $port, $sock);
             } elsif ($prot eq 'POP3'){
                 return scan_pop3($host, $port, $sock);
+            } elsif ($prot eq 'LMTP'){
+                return scan_lmtp($host, $port, $sock);
             } elsif (readline($sock)){
                 $DEBUG && write_log("$host:$port Connection OK");
                 return 1
@@ -310,6 +338,39 @@ sub scan_pop3 {
     }
 }
 
+sub scan_lmtp {
+    my $host = shift || return;
+    my $port = shift || return;
+    my $sock = shift || return;
+    my $line = readline($sock);
+    if ($line =~ m/^2\d\d /){
+        if ($LMTP_TO){
+            printf $sock "MAIL FROM:<%s>\r\n", $LMTP_FROM;
+            my $mailreply = readline($sock);
+            if ($mailreply !~ m/^2\d\d /){
+                write_err("$host:$port LMTP Server Rejects sender address");
+                return 0;
+            }
+
+            printf $sock "RCPT TO:<%s>\r\n", $LMTP_TO;
+            my $mailreply = readline($sock);
+            if ($mailreply !~ m/^2\d\d /){
+                write_err("$host:$port LMTP Server Rejects recipient address");
+                return 0;
+            }
+
+            $DEBUG && write_log("$host:$port LMTP OK");
+            return 1;
+        } else {
+            $DEBUG && write_log("$host:$port LMTP Banner OK");
+            return 1;
+        }
+    } else {
+        $DEBUG && write_log("$host:$port LMTP Banner Check Failed");
+        return 0;
+    }
+}
+
 # Extract port and protocol from combined port command-line option
 sub get_port_proto {
     my $port = shift;
@@ -320,6 +381,9 @@ sub get_port_proto {
     } elsif ($port == 110 || $port == 995 || $port =~ m/POP3:(\d+)/i){
         $port = $1 ? $1 : $port;
         return $port, 'POP3';
+    } elsif ($port == 24 || $port =~ m/LMTP:(\d+)/i){
+        $port = $1 ? $1 : $port;
+        return $port, 'LMTP';
     } else {
         return $port, 'UNKNOWN';
     }
@@ -351,12 +415,31 @@ sub enable_host {
 
 # Append a line to stdout
 sub write_log {
-    printf(STDOUT "%s LOG %s\n", strftime("%h %d %H:%M:%S", localtime()), join('', @_));
+    if ($LOGFILE eq "syslog") {
+        write_to_syslog("info", join('', @_));
+    } else {
+        printf(STDOUT "%s LOG %s\n", strftime("%h %d %H:%M:%S", localtime()), join('', @_));
+    }
 }
 
 # Append a line to stderr
 sub write_err {
-    printf(STDERR "%s ERR %s\n", strftime("%h %d %H:%M:%S", localtime()), join('', @_));
+    if ($LOGFILE eq "syslog") {
+        write_to_syslog("err", join('', @_));
+    } else {
+        printf(STDERR "%s ERR %s\n", strftime("%h %d %H:%M:%S", localtime()), join('', @_));
+    }
+}
+
+sub write_to_syslog {
+    my ($priority, $msg) = @_;
+    return 0 unless ($priority =~ /info|err|debug/);
+
+    setlogsock("unix");
+    openlog("poolmon", "pid,cons", "user");
+    syslog($priority, $msg);
+    closelog();
+    return 1;
 }
 
 # Check to see if the pidfile exists and the indicated pid is still running
@@ -367,7 +450,7 @@ sub check_pidfile {
         my $oldpid = readline($FH);
         close($FH);
         chomp $oldpid;
-        if (-d "/proc/$oldpid"){
+        if (kill(0, $oldpid)){
             write_err("Already running as pid $oldpid");
             exit(1);
         }
@@ -492,8 +575,10 @@ sub daemonize {
     chdir('/')         or die "Can't chdir to /: $!";
     umask(0);
     open(STDIN, '</dev/null')  or die "Can't read /dev/null: $!";
-    open(STDOUT, ">>$LOGFILE") or die "Can't write to $LOGFILE: $!";
-    open(STDERR, ">>$LOGFILE") or die "Can't write to $LOGFILE: $!";
+    if ($LOGFILE ne "syslog") {
+        open(STDOUT, ">>$LOGFILE") or die "Can't write to $LOGFILE: $!";
+        open(STDERR, ">>$LOGFILE") or die "Can't write to $LOGFILE: $!";
+    }
     defined(my $pid = fork())  or die "Can't fork: $!";
     $pid && exit(0);
     setsid()           or die "Can't start a new session: $!";
@@ -506,14 +591,17 @@ sub daemonize {
 
     # Reopen logfiles and reparse weights on HUP
     $SIG{'HUP'} = sub {
-        open(STDOUT, ">>$LOGFILE") or die "Can't reopen $LOGFILE: $!";
-        open(STDERR, ">>$LOGFILE") or die "Can't reopen $LOGFILE: $!";
+        if ($LOGFILE ne "syslog") {
+          open(STDOUT, ">>$LOGFILE") or die "Can't reopen $LOGFILE: $!";
+          open(STDERR, ">>$LOGFILE") or die "Can't reopen $LOGFILE: $!";
+        }
         write_log("Logfile reopened");
         load_weights();
         load_credentials();
     }
 }
 
+# Ensure pidfile cleanup on exit
 END {
     remove_pidfile();
 }

ubuntu/poolmon.conf

+description "Poolmon Dovecot Director Monitoring Daemon"
+
+start on startup
+stop on runlevel [016]
+
+kill timeout 3
+expect fork
+
+respawn
+
+exec poolmon -l syslog -c /etc/poolmon-credentials.conf