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#!/bin/sh
# ########################################################################
# This program is part of $PROJECT_NAME$
# License: GPL License (see COPYING)
# Authors:
# Baron Schwartz, Roman Vynar
# ########################################################################
# ########################################################################
# Redirect STDERR to STDOUT; Nagios doesn't handle STDERR.
# ########################################################################
exec 2>&1
# ########################################################################
# Set up constants, etc.
# ########################################################################
STATE_OK=0
STATE_WARNING=1
STATE_CRITICAL=2
STATE_UNKNOWN=3
STATE_DEPENDENT=4
# ########################################################################
# Run the program.
# ########################################################################
main() {
# Get options
for o; do
case "${o}" in
-C) shift; OPT_CHEK="${1}"; shift; ;;
-c) shift; OPT_CRIT="${1}"; shift; ;;
--defaults-file) shift; OPT_DEFT="${1}"; shift; ;;
-H) shift; OPT_HOST="${1}"; shift; ;;
-l) shift; OPT_USER="${1}"; shift; ;;
-L) shift; OPT_LOPA="${1}"; shift; ;;
-p) shift; OPT_PASS="${1}"; shift; ;;
-P) shift; OPT_PORT="${1}"; shift; ;;
-S) shift; OPT_SOCK="${1}"; shift; ;;
-w) shift; OPT_WARN="${1}"; shift; ;;
--version) grep -A2 '^=head1 VERSION' "$0" | tail -n1; exit 0 ;;
--help) perl -00 -ne 'm/^ Usage:/ && print' "$0"; exit 0 ;;
-*) echo "Unknown option ${o}. Try --help."; exit 1; ;;
esac
done
OPT_CHEK="${OPT_CHEK:-states_count}"
if [ -e '/etc/nagios/mysql.cnf' ]; then
OPT_DEFT="${OPT_DEFT:-/etc/nagios/mysql.cnf}"
fi
if is_not_sourced; then
if [ -n "$1" ]; then
echo "WARN spurious command-line options: $@"
exit 1
fi
fi
# Get processlist into a temp file.
local TEMP=$(mktemp -t "${0##*/}.XXXXXX") || exit $?
trap "rm -f '${TEMP}' >/dev/null 2>&1" EXIT
case "${OPT_CHEK}" in
states_count)
OPT_WARN=${OPT_WARN:-16}
OPT_CRIT=${OPT_CRIT:-32}
# Capture a number of types of states, add some together, take the max,
# and compare to the threshold.
mysql_exec 'SHOW PROCESSLIST\G' > "${TEMP}"
if [ $? = 0 ]; then
UNAUTH=$(count_mysql_processlist "${TEMP}" "User" "unauthenticated user")
LOCKED1=$(count_mysql_processlist "${TEMP}" "State" "Locked")
LOCKED2=$(count_mysql_processlist "${TEMP}" "State" "Waiting for .* lock")
LOCKED3=$(count_mysql_processlist "${TEMP}" "State" "Table lock")
LOCKED4=$(count_mysql_processlist "${TEMP}" "State" "Waiting for table flush")
LOCKED5=$(count_mysql_processlist "${TEMP}" "State" "Waiting for tables")
COPYIN=$(count_mysql_processlist "${TEMP}" "State" ".*opy.* to.* table.*")
STATIS=$(count_mysql_processlist "${TEMP}" "State" "statistics")
LOCKED=$((${LOCKED1:-0} + ${LOCKED2:-0} + ${LOCKED3:-0} + ${LOCKED4:-0} + ${LOCKED5:-0}))
NOTE="${UNAUTH} unauthenticated, ${LOCKED} locked,"
NOTE="${NOTE} ${COPYIN} copy to table, ${STATIS} statistics"
MAX="$(max "${UNAUTH:-0}" "${LOCKED:-0}" "${COPYIN:-0}" "${STATIS:-0}")"
if [ "${MAX:-0}" -gt "${OPT_CRIT}" ]; then
NOTE="CRIT $NOTE"
elif [ "${MAX:-0}" -gt "${OPT_WARN}" ]; then
NOTE="WARN $NOTE"
else
NOTE="OK $NOTE"
fi
# Build the common perf data output for graph trending
PERFDATA="processes=${MAX:-0};${OPT_WARN};${OPT_CRIT};0;"
NOTE="$NOTE | $PERFDATA"
else
NOTE="UNK could not retrieve MySQL processlist"
fi
;;
max_user_conn)
OPT_WARN=${OPT_WARN:-90}
OPT_CRIT=${OPT_CRIT:-95}
# Check if @@max_user_connections is set on MySQL
MAX_USER_CONN=$(mysql_exec 'SELECT @@max_user_connections')
if [ $? = 0 ]; then
if [ ${MAX_USER_CONN:-0} -gt 0 ]; then
# Capture a number of connections per user from the processlist, take the max,
# and compare to the threshold.
mysql_exec 'SHOW PROCESSLIST\G' > "${TEMP}"
if [ $? = 0 ]; then
MAX_USER=$(cat ${TEMP}|grep User|awk '{print $2}'|sort|uniq -c|sort -n|tail -1)
CNT=$(echo ${MAX_USER} | awk '{print $1}')
USER=$(echo ${MAX_USER} | awk '{print $2}')
MAX=$(expr ${CNT} \* 100 / ${MAX_USER_CONN})
NOTE="User with max connections: ${USER} (${CNT}) = ${MAX}%"
if [ "${MAX:-0}" -gt "${OPT_CRIT}" ]; then
NOTE="CRIT $NOTE"
elif [ "${MAX:-0}" -gt "${OPT_WARN}" ]; then
NOTE="WARN $NOTE"
else
NOTE="OK $NOTE"
fi
# Build the common perf data output for graph trending
PERFDATA="max_user_conn=${MAX:-0};${OPT_WARN};${OPT_CRIT};0;100"
NOTE="$NOTE | $PERFDATA"
else
NOTE="UNK could not retrieve MySQL processlist"
fi
else
NOTE="OK @@max_user_connections is not configured."
fi
else
NOTE="UNK could not retrieve @@max_user_connections"
fi
;;
*)
echo "Unknown value for -C: '${OPT_CHEK}'. Consult the documentation.";
exit 1;
;;
esac
echo $NOTE
}
# ########################################################################
# Extract a count from MySQL processlist. The arguments are:
# $1 - file with the processlist.
# $2 - the column to examine.
# $3 - the value to count.
# ########################################################################
count_mysql_processlist() {
local FILE="${1}"
local COL="${2}"
local MATCH="${3}"
grep -c "^ *${COL}: ${MATCH}" "${FILE}"
}
# ########################################################################
# Find the maximum argument, assuming nonnegative integers.
# ########################################################################
max() {
local MAX=0
for val; do
if [ "${val:-0}" -gt "${MAX}" ]; then
MAX="${val}"
fi
done
echo "${MAX:-0}"
}
# ########################################################################
# Execute a MySQL command.
# ########################################################################
mysql_exec() {
mysql ${OPT_DEFT:+--defaults-file="${OPT_DEFT}"} \
${OPT_LOPA:+--login-path="${OPT_LOPA}"} \
${OPT_HOST:+-h"${OPT_HOST}"} ${OPT_PORT:+-P"${OPT_PORT}"} \
${OPT_USER:+-u"${OPT_USER}"} ${OPT_PASS:+-p"${OPT_PASS}"} \
${OPT_SOCK:+-S"${OPT_SOCK}"} -ss -e "$1"
}
# ########################################################################
# Determine whether this program is being executed directly, or sourced/included
# from another file.
# ########################################################################
is_not_sourced() {
[ "${0##*/}" = "pmp-check-mysql-processlist" ] || [ "${0##*/}" = "bash" -a "$_" = "$0" ]
}
# ########################################################################
# Execute the program if it was not included from another file.
# This makes it possible to include without executing, and thus test.
# ########################################################################
if is_not_sourced; then
OUTPUT=$(main "$@")
EXITSTATUS=$STATE_UNKNOWN
case "${OUTPUT}" in
UNK*) EXITSTATUS=$STATE_UNKNOWN; ;;
OK*) EXITSTATUS=$STATE_OK; ;;
WARN*) EXITSTATUS=$STATE_WARNING; ;;
CRIT*) EXITSTATUS=$STATE_CRITICAL; ;;
esac
echo "${OUTPUT}"
exit $EXITSTATUS
fi
# ############################################################################
# Documentation
# ############################################################################
: <<'DOCUMENTATION'
=pod
=head1 NAME
pmp-check-mysql-processlist - Alert when MySQL processlist has dangerous patterns.
=head1 SYNOPSIS
Usage: pmp-check-mysql-processlist [OPTIONS]
Options:
-C CHECK What to alert on; default states_count.
Other options: max_user_conn.
-c CRIT Critical threshold; default varies.
--defaults-file FILE Only read mysql options from the given file.
Defaults to /etc/nagios/mysql.cnf if it exists.
-H HOST MySQL hostname.
-l USER MySQL username.
-L LOGIN-PATH Use login-path to access MySQL (with MySQL client 5.6).
-p PASS MySQL password.
-P PORT MySQL port.
-S SOCKET MySQL socket file.
-w WARN Warning threshold; default varies.
--help Print help and exit.
--version Print version and exit.
Options must be given as --option value, not --option=value or -Ovalue.
Use perldoc to read embedded documentation with more details.
=head1 DESCRIPTION
This Nagios plugin examines MySQL processlist in several ways,
depending on the value of the -C option:
=over
=item states_count
Alerts when there are too many processes in various states.
The list of checks is as follows:
Unauthenticated users appear when DNS resolution is slow, and can be a warning
sign of DNS performance problems that could cause a sudden denial of service to
the server.
Locked processes are the signature of MyISAM tables, but can also appear for
other reasons.
Too many processes copying to various kinds of temporary tables at one time is a
typical symptom of a storm of poorly optimized queries.
Too many processes in the "statistics" state is a signature of InnoDB
concurrency problems causing query execution plan generation to take too long.
The thresholds should be given as count. The default critical level is 32,
and warning is 16.
=item max_user_conn
Alerts when C<@@max_user_connections> is configured on MySQL and any user reaches
this limit. The output of this check will display the user with maximum
connections consumed, its count and percentage of the actual limit.
The thresholds should be given as percentage. The default critical level is 95,
and warning is 90.
=back
Examples:
# /usr/lib64/nagios/plugins/pmp-check-mysql-processlist
OK 0 unauthenticated, 0 locked, 0 copy to table, 0 statistics | processes=0;16;32;0;
# /usr/lib64/nagios/plugins/pmp-check-mysql-processlist -C max_user_conn
OK User with max connections: myappuser (70) = 2% | max_user_conn=2;90;95;0;100
=head1 PRIVILEGES
This plugin executes the following commands against MySQL:
=over
=item *
C<SHOW PROCESSLIST;>
=item *
C<SELECT @@max_user_connections;>
=back
This plugin executes no UNIX commands that may need special privileges.
=head1 COPYRIGHT, LICENSE, AND WARRANTY
This program is copyright 2012-$CURRENT_YEAR$ Baron Schwartz, 2012-$CURRENT_YEAR$ Percona Inc.
Feedback and improvements are welcome.
THIS PROGRAM IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED
WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
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, version 2. 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., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA.
=head1 VERSION
$PROJECT_NAME$ pmp-check-mysql-processlist $VERSION$
=cut
DOCUMENTATION
|