#!/usr/bin/perl use strict; my $VERSION = '0.1.1'; my $COPYRIGHT = 'Copyright (C) 2008 Jonathan Buhacoff '; my $LICENSE = 'http://www.gnu.org/licenses/gpl.txt'; my %status = ( 'OK' => 0, 'WARNING' => 1, 'CRITICAL' => 2, 'UNKNOWN' => 3 ); my $SERVICE = "MYSQL SLAVE"; # look for required modules exit $status{UNKNOWN} unless load_modules(qw/Getopt::Long DBI DBD::mysql/); Getopt::Long::Configure("bundling"); my $verbose = 0; my $help = ""; my $help_usage = ""; my $show_version = ""; my $mysql_server = ""; my $default_mysql_port = "3306"; my $mysql_port = ""; my $warntime = 15; my $criticaltime = 30; my $timeout = 60; my $username = ""; my $password = ""; my $ok; $ok = Getopt::Long::GetOptions( "V|version"=>\$show_version, "v|verbose+"=>\$verbose,"h|help"=>\$help,"usage"=>\$help_usage, "w|warning=i"=>\$warntime,"c|critical=i"=>\$criticaltime,"t|timeout=i"=>\$timeout, # mysql settings "H|hostname=s"=>\$mysql_server,"p|port=i"=>\$mysql_port, "U|username=s"=>\$username,"P|password=s"=>\$password, ); if( $show_version ) { print "$VERSION\n"; if( $verbose ) { print "Default warning threshold: $warntime seconds\n"; print "Default critical threshold: $criticaltime seconds\n"; print "Default timeout: $timeout seconds\n"; } exit $status{UNKNOWN}; } if( $help ) { exec "perldoc", $0 or print "Try `perldoc $0`\n"; exit $status{UNKNOWN}; } $help_usage = 1 unless $mysql_server and $username; if( $help_usage ) { print "Usage: $0 -H host [-p port] [-U username] [-P password] [-w ] [-c ]\n"; exit $status{UNKNOWN}; } # initialize my $report = new PluginReport; my $time_start = time; my $actual_response = undef; # connect to MySQL server $mysql_port = $default_mysql_port unless $mysql_port; eval { local $SIG{ALRM} = sub { die "exceeded timeout $timeout seconds\n" }; # NB: \n required, see `perldoc -f alarm` alarm $timeout; my $dbh = DBI->connect("DBI:mysql:host=$mysql_server;port=$mysql_port",$username,$password); # get mysql version my $version = undef; my $sth_version = $dbh->prepare("SHOW VARIABLES LIKE 'version'"); $sth_version->execute; while( my ($name,$value) = $sth_version->fetchrow_array) { $version = $value if $name eq "version"; } $report->{version} = $version || ""; $sth_version->finish; # get slave status (should only be 1 result row) my $sth_status = $dbh->prepare("SHOW SLAVE STATUS"); $sth_status->execute; while( my $status = $sth_status->fetchrow_hashref) { if( $verbose > 1 ) { foreach( keys %$status ) { print "$_ = $status->{$_} \n"; } } # mysql 3.23 has "Slave_Running" while 4.1 and above have "Slave_IO_Running" and "Slave_SQL_Running" $report->{Running} = "No"; if( $version lt "4" ) { $report->{Running} = "Yes" if $status->{Slave_Running}; $report->{file} = $status->{Log_File}; $report->{position} = $status->{Pos}; } else { $report->{Running} = "Yes" if $status->{Slave_IO_Running} eq "Yes" and $status->{Slave_SQL_Running} eq "Yes"; $report->{file} = $status->{Master_Log_File}; $report->{position} = $status->{Exec_Master_Log_Pos} . '/' . $status->{Read_Master_Log_Pos}; } $report->{behind} = $status->{Seconds_Behind_Master}; # put the master host and its bin log file and position in the report foreach( keys %$status ) { $report->{$_} = $status->{$_}; } } $sth_status->finish; # threshold for seconds behind master etc. # $report->{behind} = ... $report->{behind} ||= 0; # $report->{saomethaisdf} ... $dbh->disconnect; }; if( $@ ) { $@ = $DBI::errstr if $DBI::errstr; # these can be more helpful than "Can't call method prepare on an undefined value" $@ =~ s/\n/ /g; # the error message can be multiline but we want our output to be just one line print "$SERVICE CRITICAL - $@\n"; exit $status{CRITICAL}; } my @warning = (); my @critical = (); # overall warnings/critical cerrors push @critical, "not running $report->{Last_Error}" if $report->{Running} ne "Yes"; push @critical, "$report->{behind} secs behind master" if $report->{behind} > 30; push @warning, "$report->{behind} secs behind master" if $report->{behind} > 0; #push @warning, "connection time more than $warntime" if( $time_connected - $time_start > $warntime ); #push @critical, "connection time more than $criticaltime" if( $time_connected - $time_start > $criticaltime ); #push @critical, "response was $actual_response but expected $expect_response" if ( $actual_response ne $expect_response ); # on the number line, we need to test 6 cases: # 0-----w-----c-----> # 0, 0=c, w<=lagtext(qw/file position/); my $long_report = join("", map { "$_: $report->{$_}\n" } qw/version Master_Host Log_File Pos/ ); if( scalar @critical ) { my $crit_alerts = join(", ", @critical); print "$SERVICE CRITICAL - $crit_alerts; $short_report\n"; print $long_report if $verbose; exit $status{CRITICAL}; } if( scalar @warning ) { my $warn_alerts = join(", ", @warning); print "$SERVICE WARNING - $warn_alerts; $short_report\n"; print $long_report if $verbose; exit $status{WARNING}; } print "$SERVICE OK - $short_report\n"; print $long_report if $verbose; exit $status{OK}; # utility to load required modules. exits if unable to load one or more of the modules. sub load_modules { my @missing_modules = (); foreach( @_ ) { eval "require $_"; push @missing_modules, $_ if $@; } if( @missing_modules ) { print "Missing perl modules: @missing_modules\n"; return 0; } return 1; } # NAME # PluginReport # SYNOPSIS # $report = new PluginReport; # $report->{label1} = "value1"; # $report->{label2} = "value2"; # print $report->text(qw/label1 label2/); package PluginReport; sub new { my ($proto,%p) = @_; my $class = ref($proto) || $proto; my $self = bless {}, $class; $self->{$_} = $p{$_} foreach keys %p; return $self; } sub text { my ($self,@labels) = @_; my @report = map { "$_ $self->{$_}" } grep { defined $self->{$_} } @labels; my $text = join(", ", @report); return $text; } package main; 1; __END__ =pod =head1 NAME check_mysql_slave - connects to a mysql replication slave and checks its status =head1 SYNOPSIS check_mysql_slave -H slave.server.net -U nagios -P passwd check_mysql_slave -H slave.server.net -U nagios -P passwd -p 3306 check_mysql_slave --help =head1 OPTIONS =over =item --warning Currently not used. There are other nagios plugins that will check if a server is responding to connections. May be used in the future to specify how many bytes or seconds behind the master a slave may be. Also known as: -w =item --critical Currently not used. There are other nagios plugins that will check if a server is responding to connections. May be used in the future to specify how many bytes or seconds behind the master a slave may be. Also known as: -c =item --timeout Abort with critical status if it takes longer than to connect to the mysql server. Default is 60 seconds. Also known as: -t =item --hostname Address or name of the MySQL slave server. Examples: mysql5.server.net, localhost, 192.168.1.100 Also known as: -H =item --port Service port on the MySQL server. Default is 3306. Also known as: -p =item --username =item --password Username and password to use when connecting to the MySQL server. Also known as: -U -P =item --verbose Display additional information. Useful for troubleshooting. Use together with --version to see the default warning and critical timeout values. Also known as: -v =item --version Display plugin version and exit. Also known as: -V =item --help Display this documentation and exit. Does not work in the ePN version. Also known as: -h =item --usage Display a short usage instruction and exit. =back =head1 EXAMPLES =head2 Command line example Check a slave listening on the standard MySQL port from the command line: $ check_mysql_slave -H slave.server.net -U nagios -P 'password' MYSQL SLAVE OK - file bin.000003, position 41267/41267 =head2 Nagios configuration example I prefer to define this service on each slave: define command { command_name check_mysql_slave command_line $USER1$/check_mysql_slave -H $HOSTADDRESS$ -p 3306 -U $ARG1$ -P $ARG2$ } define service { use your-service-template host_name slave.server.net service_description MySQL Replication Slave check_command check_mysql_slave!nagios!password } But of course you could make the port number an argument and even define all your slave replication services on the master mysql host and use the slave server's hostname as an argument instead of HOSTADDRESS, like this: command_line $USER1$/check_mysql_slave -H $ARG1$ -p $ARG2$ -U $ARG3$ -P $ARG4$ check_command check_mysql_slave!slave.server.net!3306!nagios!password =head2 Nagios Embedded-Perl (ePN) example The usage is the same, but use the embedded-perl version of the plugin: command_line $USER1$/check_mysql_slave_epn -H $ARG1$ -p $ARG2$ -U $ARG3$ -P $ARG4$ =head1 EXIT CODES This plugin complies with the Nagios plug-in specification: 0 OK The plugin was able to check the service and it appeared to be functioning properly 1 Warning The plugin was able to check the service, but it appeared to be above some "warning" threshold or did not appear to be working properly 2 Critical The plugin detected that either the service was not running or it was above some "critical" threshold 3 Unknown Invalid command line arguments were supplied to the plugin or the plugin was unable to check the status of the given hosts/service =head1 NAGIOS PLUGIN NOTES Nagios plugin reference: http://nagiosplug.sourceforge.net/developer-guidelines.html This plugin does NOT use Nagios DEFAULT_SOCKET_TIMEOUT (provided by utils.pm as $TIMEOUT) because the path to utils.pm must be specified completely in this program and forces users to edit the source code if their install location is different (if they realize this is the problem). You can view the default timeout for this module by using the --verbose and --version options together. The short form is -vV. Other than that, it attempts to follow published guidelines for Nagios plugins. =head1 SECURITY AND MYSQL PRIVILEGES This section concerns mysql administrators who want to grant only minimal privileges to the nagios plugin (since its username and password are stored in the nagios config!). The plugin executes the following commands on slave servers: SHOW VARIABLES LIKE 'version'; SHOW SLAVE STATUS; I recommend using the following minimal grants for the nagios plugin: =head2 MySQL version 3.23 GRANT PROCESS ON *.* TO 'nagios'@'nagios.server.net' identified by 'password'; =head2 MySQL version 4.1 GRANT SUPER,REPLICATION CLIENT ON *.* TO 'nagios'@'nagios.server.net' identified by 'password'; =head2 MySQL version 5.0 GRANT SUPER,REPLICATION CLIENT ON *.* TO 'nagios'@'nagios.server.net' identified by 'password'; =head1 PERL MODULE NOTES This plugin requires the following perl modules: Getopt::Long DBI DBD::mysql The manual for DBD::mysql states that a database is required in the connection string. This is not true if you are only using global privileges such as usage, process, super, or replication client without trying to open a specific database. =head1 CHANGES Tue Aug 19 17:46:02 PDT 2008 + version 0.1 Wed Aug 20 07:58:16 PDT 2008 + added helpful DBI error messages (access denied, incompatible versions, etc) + version 0.1.1 =head1 AUTHOR Jonathan Buhacoff =head1 COPYRIGHT AND LICENSE Copyright (C) 2008 Jonathan Buhacoff This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA http://www.gnu.org/licenses/gpl.txt =cut