I'm using percona-clustercheck (which comes with Percona's XtraDB Cluster packages) with xinetd and I'm getting an error when trying to curl the clustercheck service.
/usr/bin/clustercheck:
#!/bin/bash
#
# Script to make a proxy (ie HAProxy) capable of monitoring Percona XtraDB Cluster nodes properly
#
# Author: Olaf van Zandwijk <
[email protected]>
# Documentation and download: https://github.com/olafz/percona-clustercheck
#
# Based on the original script from Unai Rodriguez
#
MYSQL_USERNAME="clustercheckuser"
MYSQL_PASSWORD="clustercheckpassword!"
ERR_FILE="/dev/null"
AVAILABLE_WHEN_DONOR=0
#
# Perform the query to check the wsrep_local_state
#
WSREP_STATUS=`mysql --user=${MYSQL_USERNAME} --password=${MYSQL_PASSWORD} -e "SHOW STATUS LIKE 'wsrep_local_state';" 2>${ERR_FILE} | awk '{if (NR!=1){print $2}}' 2>${ERR_FILE}`
if [[ "${WSREP_STATUS}" == "4" ]] || [[ "${WSREP_STATUS}" == "2" && ${AVAILABLE_WHEN_DONOR} == 1 ]]
then
# Percona XtraDB Cluster node local state is 'Synced' => return HTTP 200
/bin/echo -en "HTTP/1.1 200 OK\r\n"
/bin/echo -en "Content-Type: text/plain\r\n"
/bin/echo -en "\r\n"
/bin/echo -en "Percona XtraDB Cluster Node is synced.\r\n"
/bin/echo -en "\r\n"
exit 0
else
# Percona XtraDB Cluster node local state is not 'Synced' => return HTTP 503
/bin/echo -en "HTTP/1.1 503 Service Unavailable\r\n"
/bin/echo -en "Content-Type: text/plain\r\n"
/bin/echo -en "\r\n"
/bin/echo -en "Percona XtraDB Cluster Node is not synced.\r\n"
/bin/echo -en "\r\n"
exit 1
fi
/etc/xinetd.mysqlchk:
# default: on
# description: mysqlchk
service mysqlchk
{
# this is a config for xinetd, place it in /etc/xinetd.d/
disable = no
flags = REUSE
socket_type = stream
port = 9200
wait = no
user = nobody
server = /usr/bin/clustercheck
log_on_failure += USERID
only_from = 10.0.0.0/8 127.0.0.1
# recommended to put the IPs that need
# to connect exclusively (security purposes)
per_source = UNLIMITED
}
When attempting to curl the service, I get a valid response (HTTP 200, text) but a 'connection reset by peer' notice at the end:
HTTP/1.1 200 OK
Content-Type: text/plain
Percona XtraDB Cluster Node is synced.
curl: (56) Recv failure: Connection reset by peer
Unfortunately, Amazon
ELB appears to see this as a failed check, not a succeeded one.
How can I get clustercheck to exit gracefully in a manner that curl doesn't see a connection failure?
