#!/bin/bash
# ########################################################################
# 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 "${o}" in
-c) shift; OPT_CRIT="${1}"; shift; ;;
--defaults-file) shift; OPT_DEFT="${1}"; shift; ;;
-H) shift; OPT_HOST="${1}"; shift; ;;
-i) shift; OPT_INTERVAL="${1}"; shift; ;;
-l) shift; OPT_USER="${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; ;;
-T) shift; OPT_TABLE="${1}"; shift; ;;
-w) shift; OPT_WARN="${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 ${o}. Try --help."; exit 1; ;;
esac
done
OPT_INTERVAL=${OPT_INTERVAL:-0}
OPT_TABLE="${OPT_TABLE:-percona.checksums}"
if [ -e '/etc/nagios/mysql.cnf' ]; then
OPT_DEFT="${OPT_DEFT:-/etc/nagios/mysql.cnf}"
fi
if is_not_sourced; then
if [ -n "$1" ]; then
echo "WARN spurious command-line options: $ _æ_ "
exit 1
fi
fi
NOTE="UNK couldn't query the checksum table"
# Set up a temp file to hold error messages from MySQL.
TEMP=$(mktemp -t "${0##*/}.XXXXXX") || exit $?
trap "rm -f '${TEMP}' >/dev/null 2>&1" EXIT
# Get the query from the documentation and execute it.
SQL=$(get_magic_query "${0}" checksum_diff_query)
PROBLEMS=$(mysql_exec "${SQL/CHECKSUM_TABLE/${OPT_TABLE}}" 2>"${TEMP}")
if [ $? = 0 ]; then
if [ "${PROBLEMS}" ]; then
NOTE="pt-table-checksum found ${PROBLEMS}"
if [ "${OPT_CRIT}" ]; then
NOTE="CRIT $NOTE"
else
NOTE="WARN $NOTE"
fi
else
NOTE="OK pt-table-checksum found no out-of-sync tables"
if [ "${OPT_INTERVAL}" -gt 0 ]; then
RECENT_CHUNKS=$(mysql_exec "SELECT IF(COALESCE(MAX(ts), NOW()) > NOW() - INTERVAL ${OPT_INTERVAL} DAY, 1, 0) FROM ${OPT_TABLE}")
if [ "${RECENT_CHUNKS}" = 0 ]; then
NOTE="pt-table-checksum was not run over last ${OPT_INTERVAL} days"
if [ "${OPT_CRIT}" ]; then
NOTE="CRIT $NOTE"
else
NOTE="WARN $NOTE"
fi
fi
fi
fi
else
if grep "Table '${OPT_TABLE}' doesn't exist" "${TEMP}" >/dev/null 2>&1; then
NOTE="UNK table '${OPT_TABLE}' doesn't exist"
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"
}
# ########################################################################
# Retrieve a paragraph from the given file, which includes MAGIC_$2 as a
# pattern.
# ########################################################################
get_magic_query() {
perl -00 -ne"m/MAGIC_$2/ && print" "$1"
}
# ########################################################################
# Determine whether this program is being executed directly, or sourced/included
# from another file.
# ########################################################################
is_not_sourced() {
[ "${0##*/}" = "pmp-check-pt-table-checksum" ] || [ "${0##*/}" = "bash" -a "$_" = "$0" ]
}
# ########################################################################
# Execute the program if it was not included from another file.
# This makes it possible to include without executing, and thus test.
# ########################################################################
if is_not_sourced; then
OUTPUT=$(main "$ _æ_ ")
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-pt-table-checksum - Alert when pt-table-checksum finds data differences on a replica.
=head1 SYNOPSIS
Usage: pmp-check-pt-table-checksum [OPTIONS]
Options:
-c CRIT Raise a critical error instead of a warning.
--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.
-i INTERVAL Interval over which to ensure pt-table-checksum was run,
in days; default - not to check.
-T TABLE The checksum table; default percona.checksums
-w WARN Warning threshold; ignored.
--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 whether MySQL replication has drifted out of sync
with the master's data, according to checks performed by the pt-table-checksum
tool in Percona Toolkit. It uses the following query to determine whether the
server's data matches its master's:
SELECT /* MAGIC_checksum_diff_query */
CONCAT(
COUNT(*),
' chunks differ in ',
COUNT(DISTINCT CONCAT(db, tbl)),
' tables, including ',
MIN(CONCAT(db, '.', tbl)))
FROM CHECKSUM_TABLE
WHERE master_cnt <> this_cnt OR master_crc <> this_crc
OR ISNULL(master_crc) <> ISNULL(this_crc)
HAVING COUNT(*) > 0
The word CHECKSUM_TABLE is replaced by the value of the -T option. If the table
specified by -T does not exist, unknown is raised.
Optionally, you can specify an interval in days over which to ensure pt-table-checksum
was run. It is useful in cases when the cron job doing the checksumming suddenly
stopped working. This option will have an effect when no diffs are found and the
checksum table is not empty.
Alerts are raised at a WARNING level by default, but specifying the -c option
with any value will change this to CRITICAL instead.
=head1 PRIVILEGES
This plugin executes the following commands against MySQL:
=over
=item *
C