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Diffstat (limited to 'clustercheck.sh')
| -rw-r--r-- | clustercheck.sh | 89 |
1 files changed, 89 insertions, 0 deletions
diff --git a/clustercheck.sh b/clustercheck.sh new file mode 100644 index 0000000..3b405dc --- /dev/null +++ b/clustercheck.sh @@ -0,0 +1,89 @@ +#!/bin/bash +# +# Script to make a proxy (ie HAProxy) capable of monitoring Galera cluster nodes properly +# +# Author: Olaf van Zandwijk <olaf.vanzandwijk@nedap.com> +# Author: Raghavendra Prabhu <raghavendra.prabhu@percona.com> +# Author: Ryan O'Hara <rohara@redhat.com> +# +# Documentation and download: https://github.com/olafz/percona-clustercheck +# +# Based on the original script from Unai Rodriguez +# + +if [ -f /etc/sysconfig/clustercheck ]; then + . /etc/sysconfig/clustercheck +fi + +MYSQL_USERNAME="${MYSQL_USERNAME-clustercheckuser}" +MYSQL_PASSWORD="${MYSQL_PASSWORD-clustercheckpassword!}" +MYSQL_HOST="${MYSQL_HOST:-127.0.0.1}" +MYSQL_PORT="${MYSQL_PORT:-3306}" +ERR_FILE="${ERR_FILE:-/dev/null}" +AVAILABLE_WHEN_DONOR=${AVAILABLE_WHEN_DONOR:-0} +AVAILABLE_WHEN_READONLY=${AVAILABLE_WHEN_READONLY:-1} +DEFAULTS_EXTRA_FILE=${DEFAULTS_EXTRA_FILE:-/etc/my.cnf} + +#Timeout exists for instances where mysqld may be hung +TIMEOUT=10 + +if [[ -r $DEFAULTS_EXTRA_FILE ]];then + MYSQL_CMDLINE="mysql --defaults-extra-file=$DEFAULTS_EXTRA_FILE -nNE \ + --connect-timeout=$TIMEOUT \ + --user=${MYSQL_USERNAME} --password=${MYSQL_PASSWORD} \ + --host=${MYSQL_HOST} --port=${MYSQL_PORT}" +else + MYSQL_CMDLINE="mysql -nNE --connect-timeout=$TIMEOUT \ + --user=${MYSQL_USERNAME} --password=${MYSQL_PASSWORD} \ + --host=${MYSQL_HOST} --port=${MYSQL_PORT}" +fi +# +# Perform the query to check the wsrep_local_state +# +WSREP_STATUS=$($MYSQL_CMDLINE -e "SHOW STATUS LIKE 'wsrep_local_state';" \ + 2>${ERR_FILE} | tail -1 2>>${ERR_FILE}) + +if [[ "${WSREP_STATUS}" == "4" ]] || [[ "${WSREP_STATUS}" == "2" && ${AVAILABLE_WHEN_DONOR} == 1 ]] +then + # Check only when set to 0 to avoid latency in response. + if [[ $AVAILABLE_WHEN_READONLY -eq 0 ]];then + READ_ONLY=$($MYSQL_CMDLINE -e "SHOW GLOBAL VARIABLES LIKE 'read_only';" \ + 2>${ERR_FILE} | tail -1 2>>${ERR_FILE}) + + if [[ "${READ_ONLY}" == "ON" ]];then + # Galera cluster node local state is 'Synced', but it is in + # read-only mode. The variable AVAILABLE_WHEN_READONLY is set to 0. + # => return HTTP 503 + # Shell return-code is 1 + echo -en "HTTP/1.1 503 Service Unavailable\r\n" + echo -en "Content-Type: text/plain\r\n" + echo -en "Connection: close\r\n" + echo -en "Content-Length: 35\r\n" + echo -en "\r\n" + echo -en "Galera cluster node is read-only.\r\n" + sleep 0.1 + exit 1 + fi + fi + # Galera cluster node local state is 'Synced' => return HTTP 200 + # Shell return-code is 0 + echo -en "HTTP/1.1 200 OK\r\n" + echo -en "Content-Type: text/plain\r\n" + echo -en "Connection: close\r\n" + echo -en "Content-Length: 32\r\n" + echo -en "\r\n" + echo -en "Galera cluster node is synced.\r\n" + sleep 0.1 + exit 0 +else + # Galera cluster node local state is not 'Synced' => return HTTP 503 + # Shell return-code is 1 + echo -en "HTTP/1.1 503 Service Unavailable\r\n" + echo -en "Content-Type: text/plain\r\n" + echo -en "Connection: close\r\n" + echo -en "Content-Length: 36\r\n" + echo -en "\r\n" + echo -en "Galera cluster node is not synced.\r\n" + sleep 0.1 + exit 1 +fi |