#!/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 =item * C