120 lines
4.8 KiB
Bash
Executable File
120 lines
4.8 KiB
Bash
Executable File
#!/usr/bin/env bash
|
|
|
|
# force_single_node - Manually promote a single coordinator node from a degraded cluster
|
|
# Part of the Parallel Virtual Cluster (PVC) system
|
|
#
|
|
# Copyright (C) 2018-2020 Joshua M. Boniface <joshua@boniface.me>
|
|
#
|
|
# This program is free software: you can redistribute it and/or modify
|
|
# it under the terms of the GNU General Public License as published by
|
|
# the Free Software Foundation, either version 3 of the License, or
|
|
# (at your option) any later version.
|
|
#
|
|
# This program is distributed in the hope that it will be useful,
|
|
# but WITHOUT ANY WARRANTY; without even the implied warranty of
|
|
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
|
|
# GNU General Public License for more details.
|
|
#
|
|
# You should have received a copy of the GNU General Public License
|
|
# along with this program. If not, see <https://www.gnu.org/licenses/>.
|
|
#
|
|
###############################################################################
|
|
|
|
set -o errexit
|
|
set -o pipefail
|
|
|
|
usage() {
|
|
echo -e "Manually promote a single coordinator node from a degraded cluster"
|
|
echo -e ""
|
|
echo -e "DANGER: This action will cause a permanent split-brain within the cluster"
|
|
echo -e " which will have to be corrected manually upon cluster restoration."
|
|
echo -e ""
|
|
echo -e "This script is primarily designed for small clusters in situations where 2"
|
|
echo -e "of the 3 coordinators have become unreachable or shut down. It will promote"
|
|
echo -e "the remaining lone_node to act as a standalone coordinator, allowing basic"
|
|
echo -e "cluster functionality to continue in a heavily degraded state until the"
|
|
echo -e "situation can be rectified. This should only be done in exceptional cases"
|
|
echo -e "as a disaster recovery mechanism when the remaining nodes will remain down"
|
|
echo -e "for a significant amount of time but some VMs are required to run. In general,"
|
|
echo -e "use of this script is not advisable."
|
|
echo -e ""
|
|
echo -e "Usage:"
|
|
echo -e " $0 <target_cluster> <lone_node>"
|
|
echo -e ""
|
|
echo -e "Important information:"
|
|
echo -e " * The lone_node must be a fully-qualified name that is directly reachable from"
|
|
echo -e " the local system via SSH."
|
|
echo -e " * The local user must have valid SSH access to the lone_node in the cluster."
|
|
echo -e " * The user on the cluster node must have 'sudo' access."
|
|
}
|
|
|
|
fail() {
|
|
echo -e "$@"
|
|
exit 1
|
|
}
|
|
|
|
# Arguments
|
|
if [[ -z ${1} || -z ${2} ]]; then
|
|
usage
|
|
exit 1
|
|
fi
|
|
target_cluster="${1}"
|
|
lone_node="${2}"
|
|
lone_node_shortname="${lone_node%%.*}"
|
|
|
|
# Attempt to connect to the node
|
|
ssh ${lone_node} which pvc &>/dev/null || fail "Could not SSH to the lone_node host"
|
|
|
|
echo "Verification complete."
|
|
|
|
echo -n "Allowing Ceph single-node operation... "
|
|
temp_monmap="$( ssh ${lone_node} mktemp )"
|
|
ssh ${lone_node} "sudo systemctl stop ceph-mon@${lone_node_shortname}" &>/dev/null
|
|
ssh ${lone_node} "ceph-mon -i ${lone_node_shortname} --extract-monmap ${temp_monmap}" &>/dev/null
|
|
ssh ${lone_node} "sudo cp ${tmp_monmap} /etc/ceph/monmap.orig" &>/dev/null
|
|
mon_list="$( ssh ${lone_node} strings ${temp_monmap} | sort | uniq )"
|
|
for mon in ${mon_list}; do
|
|
if [[ ${mon} == ${lone_node_shortname} ]]; then
|
|
continue
|
|
fi
|
|
ssh ${lone_node} "sudo monmaptool ${temp_monmap} --rm ${mon}" &>/dev/null
|
|
done
|
|
ssh ${lone_node} "sudo ceph-mon -i ${lone_node_shortname} --inject-monmap ${temp_monmap}" &>/dev/null
|
|
ssh ${lone_node} "sudo systemctl start ceph-mon@${lone_node_shortname}" &>/dev/null
|
|
sleep 5
|
|
ssh ${lone_node} "sudo ceph osd set noout" &>/dev/null
|
|
echo "done."
|
|
echo -e "Restoration steps:"
|
|
echo -e " sudo systemctl stop ceph-mon@${lone_node_shortname}"
|
|
echo -e " sudo ceph-mon -i ${lone_node_shortname} --inject-monmap /etc/ceph/monmap.orig"
|
|
echo -e " sudo systemctl start ceph-mon@${lone_node_shortname}"
|
|
echo -e " sudo ceph osd unset noout"
|
|
|
|
echo -n "Allowing Zookeeper single-node operation... "
|
|
temp_zoocfg="$( ssh ${lone_node} mktemp )"
|
|
ssh ${lone_node} "sudo systemctl stop zookeeper"
|
|
ssh ${lone_node} "sudo awk -v lone_node=${lone_node_shortname} '{
|
|
FS="=|:"
|
|
if ( $1 ~ /^server/ ){
|
|
if ($2 == lone_node) {
|
|
print $0
|
|
} else {
|
|
print "#" $0
|
|
}
|
|
} else {
|
|
print $0
|
|
}
|
|
}' /etc/zookeeper/conf/zoo.cfg > ${temp_zoocfg}"
|
|
ssh ${lone_node} "sudo mv /etc/zookeeper/conf/zoo.cfg /etc/zookeeper/conf/zoo.cfg.orig"
|
|
ssh ${lone_node} "sudo mv ${temp_zoocfg} /etc/zookeeper/conf/zoo.cfg"
|
|
ssh ${lone_node} "sudo systemctl start zookeeper"
|
|
echo "done."
|
|
echo -e "Restoration steps:"
|
|
echo -e " sudo systemctl stop zookeeper"
|
|
echo -e " sudo mv /etc/zookeeper/conf/zoo.cfg.orig /etc/zookeeper/conf/zoo.cfg"
|
|
echo -e " sudo systemctl start zookeeper"
|
|
ssh ${lone_node} "sudo systemctl stop ceph-mon@${lone_node_shortname}"
|
|
|
|
echo ""
|
|
ssh ${lone_node} "sudo pvc status 2>/dev/null"
|