Einleitung
Mit diesem Skript ist es möglich die Failover-IP zu wechseln.
Usage
Der aktuelle Status abrufen:
./script database get
Die failover-IP auf die IP 10.0.1.1 umrouten:
./script database set 10.0.1.1
Datenbankserver beispiel
/etc/failover/resources/database
resource database
ip 10.0.0.1
failover_ip 10.0.1.1 10.0.1.2
user <user>
password <password>
script /etc/failover/script/startmysql
Das Skript
#!/bin/bash
#
# fail.sh v0.3 - shfmnt'ed and shellcheck'ed version by https://github.com/thomasmerz
#
para=$1
parb=$2
parc=$3
# is curl installed?
curl="$(command -v curl)"
if [ -z "$curl" ]; then
echo "Curl is not properly configured"
exit 1
fi
# Where is the robot at?
uri="https://robot-ws.your-server.de/failover.yaml"
# check if first argument is an ip
# if it is an ip, we do not need a config
if echo "$para" | grep -qE "\b(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\.(25[0-5]|2[0-4][0-9]|[01]?[0-9][0-9]?)\b" 2>/dev/null; then
if [ "$parb" == "set-and-exec" ]; then
echo "Option {set-and-exec} only available for configured services"
exit 1
elif [ -z "$parb" ]; then
echo "$0 now needs one of the following options:"
echo "usage: $0 $para {get|set} <failover-IP>"
exit 1
fi
if [ -z "$parc" ] && [ "$parb" == "set" ]; then
echo "You have to specify the IP address of the failover server"
exit 1
fi
ip=$para
stty -echo
echo "username:"
read -r user
echo "password:"
read -r pass
stty echo
else
# where will I find the config files
resourcedir="/etc/failover/resources"
resources=$(cat $resourcedir/* 2>/dev/null | grep "resource" | awk '{ print $2 }')
if [ -z "$resources" ]; then
echo "There are no properly configured resources in $resourcedir"
exit 1
fi
# check if the service is properly configured in $resourcedir
if [ -z "$para" ]; then
echo "You have to specify a service or enter an IP"
echo "configured services are:"
echo "$resources"
exit 1
fi
if ! echo "$resources" | grep -q "$para"; then
echo "$para not available"
echo "configured services are:"
echo "$resources"
exit 1
fi
ip=$(grep "^ip" "$resourcedir/$para" | awk '{ print $2 }')
if [ -z "$ip" ]; then
echo "There is no IP-address set for resource $para in $resourcedir/$para"
exit 1
fi
user=$(grep "user" "$resourcedir/$para" | awk '{ print $2 }')
pass=$(grep "password" "$resourcedir/$para" | awk '{ print $2 }')
if [ -z "$user" ]; then
echo "There is no username set for resource $para in $resourcedir/$para"
exit 1
fi
if [ -z "$pass" ]; then
echo "There is no password set for user $user in $resourcedir/$para"
exit 1
fi
fi
case "$parb" in
get)
get=$("$curl" -s -u "$user:$pass" "$uri/$ip")
if echo "$get" | grep "^error" >/dev/null 2>&1; then
echo "There is a communication error. Hetzner returned"
echo "$get"
exit 1
elif [ -z "$get" ]; then
echo "There was no response from Hetzner"
exit 1
elif echo "$get" | grep "ip" >/dev/null 2>&1 && echo "$get" | grep "server_ip" >/dev/null 2>&1 && echo "$get" | grep "active_server_ip" >/dev/null 2>&1; then
:
else
echo "This script does not know how to handle Hetzner's answer:"
echo "$get"
exit 1
fi
yamlip=$(echo "$get" | grep "^ ip" | awk '{ print $2 }')
yamlserverip=$(echo "$get" | grep "^ server_ip" | awk '{ print $2 }')
yamlactiveip=$(echo "$get" | grep "^ active_server_ip" | awk '{print $2 }')
echo "This is the active configuration of the service $para"
echo "IP address of the service: $yamlip"
echo "failover IP was ordered for: $yamlserverip"
echo "currently the IP is routed to: $yamlactiveip"
if [ "$ip" != "$para" ]; then echo "the configured failover server(s) is/are: $(grep "^failover_ip" "$resourcedir/$para" | sed -e 's/failover_ip //g')"; fi
;;
set)
if [ -z "$parc" ]; then
echo "You have to specify the IP address of the failover server"
echo "the configured failover server(s) is/are: $(grep "^failover_ip" "$resourcedir/$para" | sed -e 's/failover_ip //g')"
exit 1
fi
echo "Waiting for a response..."
set=$("$curl" -s -u "$user:$pass" "$uri/$ip" -d active_server_ip="$parc")
if echo "$set" | grep "^error" >/dev/null 2>&1; then
if echo "$set" | grep "^ status: 409" >/dev/null 2>&1; then
echo "Looks like you tried to route the failover IP to the currently selected server"
exit 1
elif echo "$set" | grep "^ status: 500" >/dev/null 2>&1; then
echo "There seems to be an error with the rerouting request on Hetzner's part"
echo "Try again later"
exit 1
elif echo "$set" | grep "^ status: 404" >/dev/null 2>&1; then
echo "Hetzner returned Error 404"
echo "Most likely the failover IP for the service is faulty"
exit 1
fi
echo "An unknown error occurred"
exit 1
elif echo "$set" | grep "^failover" >/dev/null 2>&1; then
yamlip=$(echo "$set" | grep "^ ip" | awk '{ print $2 }')
yamlserverip=$(echo "$set" | grep "^ server_ip:" | awk '{ print $2 }')
yamlactiveip=$(echo "$set" | grep "^ active_server_ip" | awk '{ print $2 }')
echo "This is the changed configuration of the service $para"
echo "IP address of the service: $yamlip"
echo "failover IP was ordered for: $yamlserverip"
echo "currently the IP is routed to: $yamlactiveip"
if [ "$ip" != "$para" ]; then echo "the configured failover server(s) is/are: $(grep "^failover_ip" "$resourcedir/$para" | sed -e 's/failover_ip //g')"; fi
fi
;;
set-and-exec)
script=$(grep "script" "$resourcedir/$para" | awk '{ print $2 }')
if [ -z "$script" ]; then
echo "There is no script set in $resourcedir/$para"
exit 1
elif [ -x "$script" ]; then
if ./"$0" "$para" set "$parc"; then $script; else exit 1; fi
elif [ -f "$script" ]; then
echo "Script is not executable"
exit 1
fi
;;
*)
if [ -n "$parb" ]; then
echo "$parb is an unknown option"
fi
echo -e "$0 needs one of the following options"
echo "usage: $0 <service> {get|set|set-and-exec} <failover-IP>"
exit 1
;;
esac