keepalived 实现 redis 主从自动切换
搭建 redis 主备环境记录，通过 keepalived 实现 HA。
环境规划
| redis master |
192.30.20.13 |
| redis slave |
192.30.20.14 |
| vip |
192.30.20.5 |
redis 安装
yum -y install gcc tcl tar xzvf redis-2.8.20.tar.gz cd redis-2.8.20 make PREFIX=/wls/redis MALLOC=libc make test make install cd utils/ ./install_server.sh #这一步可以自定义配置文件目录及名称、日志文件目录及名称、数据存放目录、可执行文件目录等。 cd /etc/init.d/ mv redis_6379 redis service redis status redis-cli --如下是 ./install_server.sh 的输出日志 Welcome to the redis service installer This script will help you easily set up a running redis server Please select the redis port for this instance: [6379] Selecting default: 6379 Please select the redis config file name [/etc/redis/6379.conf] /etc/redis/redis.conf Please select the redis log file name [/var/log/redis_6379.log] /var/log/redis.log Please select the data directory for this instance [/var/lib/redis/6379] /wls/redis Please select the redis executable path [/usr/local/bin/redis-server] Selected config: Port : 6379 Config file : /etc/redis/redis.conf Log file : /var/log/redis.log Data dir : /wls/redis Executable : /usr/local/bin/redis-server Cli Executable : /usr/local/bin/redis-cli Is this ok? Then press ENTER to go on or Ctrl-C to abort. Copied /tmp/6379.conf => /etc/init.d/redis_6379 Installing service... Successfully added to chkconfig! Successfully added to runlevels 345! Starting Redis server... Installation successful!
keepalived 安装
yum -y install openssl-devel tar xzvf keepalived-1.2.13.tar.gz cd keepalived-1.2.13 ./configure --sysconf=/etc --with-kernel-dir=/usr/src/linux make && make install ln -s /usr/local/sbin/keepalived /sbin/keepalived chkconfig keepalived on service keepalived status
配置文件
192.30.20.13 配置
keepalived 配置
vrrp_script 和 track_script
vrrp_script代码块是用来定义监控脚本，脚本执行时间间隔以及脚本的执行结果导致优先级变更幅度的，VRRP脚本(vrrp_script)和VRRP实例(vrrp_instance)属于同一个级别，定义好vrrp_script代码块之后，就可以在instance中使用了。
vrrp_script chk_redis {
script "/etc/keepalived/scripts/redis_check.sh" #指定执行脚本的路径
interval 1 #指定脚本的执行时间间隔
weight 10 #脚本结果导致的优先级变更：10表示优先级+10；-10则表示优先级-10
}
notify 状态
notify_master keepalived切换到master时执行的脚本
notify_backup keepalived切换到backup时执行的脚本
notify_fault keepalived出现故障时执行的脚本
notify_stop keepalived停止运行前执行的脚本
! Configuration File for keepalived
vrrp_script chk_redis {
script "/etc/keepalived/scripts/redis_check.sh"
interval 2
}
vrrp_instance VI_1 {
state MASTER
interface eth0
virtual_router_id 51
priority 101
authentication {
auth_type PASS
auth_pass redis
}
track_script {
chk_redis
}
virtual_ipaddress {
192.30.20.5
}
notify_master /etc/keepalived/scripts/redis_master.sh
notify_backup /etc/keepalived/scripts/redis_backup.sh
notify_fault /etc/keepalived/scripts/redis_fault.sh
notify_stop /etc/keepalived/scripts/redis_stop.sh
}
相关 shell 脚本
sleep 的时间要根据具体情况调整。
#for file in `ls`; do echo "-----------"$file;cat $file; echo -e "\n"; done -----------redis_backup.sh #!/bin/bash REDISCLI="/usr/local/bin/redis-cli" LOGFILE="/var/log/keepalived-redis-state.log" echo "[backup]" >> $LOGFILE date >> $LOGFILE echo "Being slave...">> $LOGFILE 2>&1 sleep 15 echo "Run SLAVEOF cmd..." >> $LOGFILE $REDISCLI SLAVEOF 192.30.20.14 6379 >> $LOGFILE 2>&1 -----------redis_check.sh #!/bin/bash ALIVE=`/usr/local/bin/redis-cli PING` if [ "$ALIVE" == "PONG" ]; then echo $ALIVE exit 0 else echo $ALIVE exit 1 fi -----------redis_fault.sh #!/bin/bash LOGFILE=/var/log/keepalived-redis-state.log echo "[fault]" >> $LOGFILE date >> $LOGFILE -----------redis_master.sh #!/bin/bash REDISCLI="/usr/local/bin/redis-cli" LOGFILE="/var/log/keepalived-redis-state.log" echo "[master]" >> $LOGFILE date >> $LOGFILE echo "Being master..." >> $LOGFILE 2>&1 echo "Run SLAVEOF cmd..." >> $LOGFILE $REDISCLI SLAVEOF 192.30.20.14 6379 >> $LOGFILE 2>&1 sleep 10 echo "Run SLAVEOF NO ONE cmd..." >> $LOGFILE $REDISCLI SLAVEOF NO ONE >> $LOGFILE 2>&1 -----------redis_stop.sh #!/bin/bash LOGFILE=/var/log/keepalived-redis-state.log echo "[stop]" >> $LOGFILE date >> $LOGFILE
redis 配置（基本是默认配置）
除了 “appendonly yes”和 "pidfile /var/run/redis.pid" 这两个配置项之外，其它都默认了，master 和 slave 节点一样。
#cat /etc/redis/redis.conf | grep -v ^# | grep -v ^$ daemonize yes pidfile /var/run/redis.pid port 6379 tcp-backlog 511 timeout 0 tcp-keepalive 0 loglevel notice logfile /var/log/redis.log databases 16 save 900 1 save 300 10 save 60 10000 stop-writes-on-bgsave-error yes rdbcompression yes rdbchecksum yes dbfilename dump.rdb dir /wls/redis slave-serve-stale-data yes slave-read-only yes repl-diskless-sync no repl-diskless-sync-delay 5 repl-disable-tcp-nodelay no slave-priority 100 appendonly yes appendfilename "appendonly.aof" appendfsync everysec no-appendfsync-on-rewrite no auto-aof-rewrite-percentage 100 auto-aof-rewrite-min-size 64mb aof-load-truncated yes lua-time-limit 5000 slowlog-log-slower-than 10000 slowlog-max-len 128 latency-monitor-threshold 0 notify-keyspace-events "" hash-max-ziplist-entries 512 hash-max-ziplist-value 64 list-max-ziplist-entries 512 list-max-ziplist-value 64 set-max-intset-entries 512 zset-max-ziplist-entries 128 zset-max-ziplist-value 64 hll-sparse-max-bytes 3000 activerehashing yes client-output-buffer-limit normal 0 0 0 client-output-buffer-limit slave 256mb 64mb 60 client-output-buffer-limit pubsub 32mb 8mb 60 hz 10 aof-rewrite-incremental-fsync yes
192.30.20.14 配置
keepalived 配置
! Configuration File for keepalived
vrrp_script chk_redis {
script "/etc/keepalived/scripts/redis_check.sh"
interval 2
}
vrrp_instance VI_1 {
state BACKUP
interface eth0
virtual_router_id 51
priority 100
authentication {
auth_type PASS
auth_pass redis
}
track_script {
chk_redis
}
virtual_ipaddress {
192.30.20.5
}
notify_master /etc/keepalived/scripts/redis_master.sh
notify_backup /etc/keepalived/scripts/redis_backup.sh
notify_fault /etc/keepalived/scripts/redis_fault.sh
notify_stop /etc/keepalived/scripts/redis_stop.sh
}
相关 shell 脚本
#for file in `ls`; do echo "-----------"$file;cat $file; echo -e "\n"; done -----------redis_backup.sh #!/bin/bash REDISCLI="/usr/local/bin/redis-cli" LOGFILE="/var/log/keepalived-redis-state.log" echo "[backup]" >> $LOGFILE date >> $LOGFILE echo "Being slave..." >> $LOGFILE 2>&1 sleep 15 echo "Run SLAVEOF cmd..." >> $LOGFILE $REDISCLI SLAVEOF 192.30.20.13 6379 >> $LOGFILE 2>&1 -----------redis_check.sh #!/bin/bash ALIVE=`/usr/local/bin/redis-cli PING` if [ "$ALIVE" == "PONG" ]; then echo $ALIVE exit 0 else echo $ALIVE exit 1 fi -----------redis_fault.sh #!/bin/bash LOGFILE=/var/log/keepalived-redis-state.log echo "[fault]" >> $LOGFILE date >> $LOGFILE -----------redis_master.sh #!/bin/bash REDISCLI="/usr/local/bin/redis-cli" LOGFILE="/var/log/keepalived-redis-state.log" echo "[master]" >> $LOGFILE date >> $LOGFILE echo "Being master..." >> $LOGFILE 2>&1 echo "Run SLAVEOF cmd..." >> $LOGFILE $REDISCLI SLAVEOF 192.30.20.13 6379 >> $LOGFILE 2>&1 sleep 10 echo "Run SLAVEOF NO ONE cmd..." >> $LOGFILE $REDISCLI SLAVEOF NO ONE >> $LOGFILE 2>&1 -----------redis_stop.sh #!/bin/bash LOGFILE=/var/log/keepalived-redis-state.log echo "[stop]" >> $LOGFILE date >> $LOGFILE
redis 配置（基本是默认配置）
#cat /etc/redis/redis.conf | grep -v ^# | grep -v ^$ daemonize yes pidfile /var/run/redis.pid port 6379 tcp-backlog 511 timeout 0 tcp-keepalive 0 loglevel notice logfile /var/log/redis.log databases 16 save 900 1 save 300 10 save 60 10000 stop-writes-on-bgsave-error yes rdbcompression yes rdbchecksum yes dbfilename dump.rdb dir /wls/redis slave-serve-stale-data yes slave-read-only yes repl-diskless-sync no repl-diskless-sync-delay 5 repl-disable-tcp-nodelay no slave-priority 100 appendonly yes appendfilename "appendonly.aof" appendfsync everysec no-appendfsync-on-rewrite no auto-aof-rewrite-percentage 100 auto-aof-rewrite-min-size 64mb aof-load-truncated yes lua-time-limit 5000 slowlog-log-slower-than 10000 slowlog-max-len 128 latency-monitor-threshold 0 notify-keyspace-events "" hash-max-ziplist-entries 512 hash-max-ziplist-value 64 list-max-ziplist-entries 512 list-max-ziplist-value 64 set-max-intset-entries 512 zset-max-ziplist-entries 128 zset-max-ziplist-value 64 hll-sparse-max-bytes 3000 activerehashing yes client-output-buffer-limit normal 0 0 0 client-output-buffer-limit slave 256mb 64mb 60 client-output-buffer-limit pubsub 32mb 8mb 60 hz 10 aof-rewrite-incremental-fsync yes
添加密码认证后需要修改的地方
1. redis 命令
# 如下添加了 -a password
cat /etc/init.d/redis
#!/bin/sh
#Configurations injected by install_server below....
EXEC=/usr/local/bin/redis-server
CLIEXEC=/usr/local/bin/redis-cli
PIDFILE=/var/run/redis.pid
CONF="/etc/redis/redis.conf"
REDISPORT="6379"
###############
# SysV Init Information
# chkconfig: - 58 74
# description: redis_6379 is the redis daemon.
### BEGIN INIT INFO
# Provides: redis_6379
# Required-Start: $network $local_fs $remote_fs
# Required-Stop: $network $local_fs $remote_fs
# Default-Start: 2 3 4 5
# Default-Stop: 0 1 6
# Should-Start: $syslog $named
# Should-Stop: $syslog $named
# Short-Description: start and stop redis_6379
# Description: Redis daemon
### END INIT INFO
case "$1" in
start)
if [ -f $PIDFILE ]
then
echo "$PIDFILE exists, process is already running or crashed"
else
echo "Starting Redis server..."
$EXEC $CONF
fi
;;
stop)
if [ ! -f $PIDFILE ]
then
echo "$PIDFILE does not exist, process is not running"
else
PID=$(cat $PIDFILE)
echo "Stopping ..."
$CLIEXEC -a password -p $REDISPORT shutdown
while [ -x /proc/${PID} ]
do
echo "Waiting for Redis to shutdown ..."
sleep 1
done
echo "Redis stopped"
fi
;;
status)
PID=$(cat $PIDFILE)
if [ ! -x /proc/${PID} ]
then
echo 'Redis is not running'
else
echo "Redis is running ($PID)"
fi
;;
restart)
$0 stop
$0 start
;;
*)
echo "Please use start, stop, restart or status as first argument"
;;
esac
2. 配置文件
more /etc/redis/redis.conf |grep -E "masterauth|requirepass"
# If the master is password protected (using the "requirepass" configuration
masterauth password
requirepass password
3. keepalived 脚本
[root@payun scripts]# ls -l
total 20
-rwxr-xr-x 1 root root 295 Oct 20 11:12 redis_backup.sh
-rwxr-xr-x 1 root root 151 Oct 20 11:48 redis_check.sh
-rwxr-xr-x 1 root root 102 Sep 19 12:13 redis_fault.sh
-rwxr-xr-x 1 root root 396 Oct 20 11:12 redis_master.sh
-rwxr-xr-x 1 root root 99 Sep 18 21:05 redis_stop.sh
[root@payun scripts]#
[root@payun scripts]# cat *.sh | grep -E "REDISCLI|redis-cli" | grep -v ^REDISCLI
$REDISCLI -a password SLAVEOF 172.30.20.13 6379 >> $LOGFILE 2>&1
ALIVE=`/usr/local/bin/redis-cli -a password PING`
$REDISCLI -a password SLAVEOF 172.30.20.13 6379 >> $LOGFILE 2>&1
$REDISCLI -a password SLAVEOF NO ONE >> $LOGFILE 2>&1
[root@payun scripts]#