#!/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:-idle_blocker_duration}" 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: $@" exit 1 fi fi NOTE="UNK could not find information about transactions" local TEMP=$(mktemp -t "${0##*/}.XXXXXX") || exit $? trap "rm -f '${TEMP}' >/dev/null 2>&1" EXIT case "${OPT_CHEK}" in idle_blocker_duration) OPT_WARN=${OPT_WARN:-60} OPT_CRIT=${OPT_CRIT:-600} OUTPUT=$(mysql_exec " SELECT MAX(COALESCE(p.time, 0)) AS idle_in_trx, p.id, CONCAT(p.user, '@', p.host) AS userhost FROM INFORMATION_SCHEMA.INNODB_LOCK_WAITS AS w INNER JOIN INFORMATION_SCHEMA.INNODB_TRX AS b ON b.trx_id = w.blocking_trx_id INNER JOIN INFORMATION_SCHEMA.INNODB_TRX AS r ON r.trx_id = w.requesting_trx_id LEFT JOIN INFORMATION_SCHEMA.PROCESSLIST AS p ON p.id = b.trx_mysql_thread_id AND p.command = 'Sleep' GROUP BY p.id, p.user, p.host ORDER BY idle_in_trx DESC LIMIT 1" 2>"${TEMP}") if [ "$?" != 0 ]; then if grep "Unknown table" "${TEMP}" >/dev/null 2>&1; then # The I_S tables don't exist. NOTE="OK The INFORMATION_SCHEMA.INNODB_% tables don't exist." else cat "${TEMP}" fi elif [ -z "${OUTPUT}" ]; then OUTPUT=0 fi ;; waiter_count) OPT_WARN=${OPT_WARN:-10} OPT_CRIT=${OPT_CRIT:-25} OUTPUT=$(mysql_exec " SELECT COUNT(DISTINCT REQUESTING_TRX_ID) AS cnt FROM INFORMATION_SCHEMA.INNODB_LOCK_WAITS AS w" 2>"${TEMP}") if [ "$?" != 0 ]; then if grep "Unknown table" "${TEMP}" >/dev/null 2>&1; then # The I_S tables don't exist. mysql_exec "SHOW /*!50000 ENGINE*/ INNODB STATUS\G" > "${TEMP}" || exit $? OUTPUT=$(get_waiter_count "${TEMP}") else cat "${TEMP}" fi fi ;; max_duration) OPT_WARN=${OPT_WARN:-60} OPT_CRIT=${OPT_CRIT:-600} OUTPUT=$(mysql_exec " SET @@time_zone='SYSTEM'; SELECT UNIX_TIMESTAMP() - UNIX_TIMESTAMP(t.trx_started), p.id, CONCAT(p.user, '@', p.host) FROM INFORMATION_SCHEMA.INNODB_TRX AS t JOIN INFORMATION_SCHEMA.PROCESSLIST AS p ON p.id = t.trx_mysql_thread_id ORDER BY t.trx_started LIMIT 1" 2>"${TEMP}") if [ "$?" != 0 ]; then if grep "Unknown table" "${TEMP}" >/dev/null 2>&1; then # The I_S tables don't exist. mysql_exec "SHOW /*!50000 ENGINE*/ INNODB STATUS\G" > "${TEMP}" || exit $? OUTPUT=$(get_longest_trx "${TEMP}") if [ -z "${OUTPUT}" ]; then OUTPUT=0 fi else cat "${TEMP}" fi elif [ -z "${OUTPUT}" ]; then OUTPUT=0 fi ;; *) echo "Unknown value for -C: '${OPT_CHEK}'. Consult the documentation."; exit 1; ;; esac # $OUTPUT now contains either an empty string or three words: 1) Age of # oldest transaction, 2) thread ID of oldest transaction, 3) user info. if [ -n "${OUTPUT}" ]; then LEVEL="$(echo ${OUTPUT} | awk '{print $1}')" INFO="$(echo ${OUTPUT} | awk '{print "(thread "$2" by "$3")"}')" case "${OPT_CHEK}" in idle_blocker_duration) NOTE="longest blocking idle transaction sleeps for ${LEVEL:-UNKNOWN} seconds" ;; waiter_count) NOTE="${LEVEL:-UNKNOWN} transactions in LOCK WAIT status" INFO="" ;; max_duration) NOTE="longest transaction active for ${LEVEL:-UNKNOWN} seconds" ;; esac if [ "${LEVEL:-0}" -gt "${OPT_CRIT}" ]; then NOTE="CRIT $NOTE $INFO" elif [ "${LEVEL:-0}" -gt "${OPT_WARN}" ]; then NOTE="WARN $NOTE $INFO" else NOTE="OK $NOTE" fi fi echo $NOTE } # ######################################################################## # 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" } # ######################################################################## # Gets max txn time in SHOW INNODB STATUS. File is $1. # ######################################################################## get_longest_trx() { awk ' BEGIN { maxtime = 0; thread = 0; userinfo = "nobody"; } /^TRANSACTIONS$/ { tseen = 1; } { if ( tseen == 1 && $0 ~ /^---TRANSACTION.*[0-9] sec/ ) { if ( $2 ~ /,/ ) { time = $4; } else { time = $5; } } if ( tseen == 1 && $0 ~ /^MySQL thread id/ ) { if ( time > maxtime ) { maxtime = time; thread = substr($4, 1, length($4) - 1); match($0, /query id [0-9]+ .+/); userinfo = substr($0, RSTART, RLENGTH); split(userinfo, a, " "); userinfo = a[5]"@"a[4]; } } } END { print maxtime, thread, userinfo; } ' "${1}" } # ######################################################################## # Counts the number of LOCK WAIT in SHOW INNODB STATUS. File is $1. # ######################################################################## get_waiter_count() { awk ' BEGIN { lock_waits = 0; } /^TRANSACTIONS$/ { tseen = 1; } { if ( tseen == 1 && $0 ~ /TRX HAS BEEN WAITING/ ) { lock_waits++; } } END { print lock_waits; } ' "${1}" } # ######################################################################## # Determine whether this program is being executed directly, or sourced/included # from another file. # ######################################################################## is_not_sourced() { [ "${0##*/}" = "pmp-check-mysql-innodb" ] || [ "${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-innodb - Alert on problems inside InnoDB. =head1 SYNOPSIS Usage: pmp-check-mysql-innodb [OPTIONS] Options: -C CHECK What to alert on; default idle_blocker_duration. Other options: waiter_count, max_duration. -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 alerts on various aspects of InnoDB status in several ways, depending on the value of the -C option: =over =item idle_blocker_duration This is the default behavior. It alerts when a long-running transaction is blocking another, and the blocker is idle (Sleep). The threshold is based on how long the transaction has been idle. Long-running idle transactions that have acquired locks but not released them are a frequent cause of application downtime due to lock wait timeouts and rollbacks, especially because applications are often not designed to handle such errors correctly. The problem is usually due to another error that causes a transaction not to be committed, such as performing very long tasks in the application while holding the transaction open. This check examines the INFORMATION_SCHEMA tables included with InnoDB version 1.0 and newer. The default critical level is 600, and warning is 60. If the tables do not exist, the exit status is OK, with a note that the tables do not exist. =item waiter_count Alerts if too many transactions are in LOCK WAIT status. Uses information from SHOW ENGINE INNODB STATUS if the INFORMATION_SCHEMA tables are not available. The default critical level is 25, and warning is 10. =item max_duration Alerts if any transaction is too old. Uses information from SHOW ENGINE INNODB STATUS if the INFORMATION_SCHEMA tables are not available. The default critical level is 600, and warning is 60. =back =head1 PRIVILEGES This plugin executes the following commands against MySQL: =over =item * C. =item * C