redis + keepalived 双主模型
架构图：
1.vip默认绑定在redis主上，由redis主提供服务，redis从为备用节点。（实际上提供服务的只是vip） 2.当redis主挂掉，vip会默认漂移至redis从。由redis从提供服务，redis主已经挂掉。 3.当redis主已经恢复，redis从继续提供服务和挂载vip. 4.当redis从挂掉，vip会漂移到redis主上。当你修复好redis从，默认他会同步数据，然后变成备用节点。 5.只要redis主从不全挂，基本上是不会影响的。从而实现了双主的模型。（此双主并不是同时写数据，只是逻辑上的双主）
操作系统：centos 6.6 64bit
keepalived + redis主 ： 192.168.155.205
keepalived + redis从 ： 192.168.155.206
vip：192.168.155.207
1.两台redis环境准备工作（两台都做）
[root@web01 ~]# yum install vim gcc telnet wget lrzsz openssl openssl-devel openssl-clients ntpdate -y [root@web01 ~]# sed -i 's@SELINUX=enforcing@SELINUX=disabled@g' /etc/sysconfig/selinux [root@web01 ~]# setenforce 0 [root@web01 ~]# /etc/init.d/iptables stop [root@web01 ~]# chkconfig iptables off [root@web01 ~]# ntpdate time.nist.gov 分别修改主机名为redis_master 和 redis_slave [root@web01 ~]# vim /etc/sysconfig/network HOSTNAME=redis_master [root@web02 ~]# vim /etc/sysconfig/network HOSTNAME=redis_slave
两台机器分别重启(不重启机器也可以，使用hostname修改主机名，然后使用bash命令.)
2.两台机器分别安装redis(两台都做)
[root@redis_master ~]# wget http://download.redis.io/releases/redis-3.2.0.tar.gz [root@redis_master ~]# tar xf redis-3.2.0.tar.gz [root@redis_master ~]# mkdir -p /usr/local/redis [root@redis_master ~]# mv redis-3.2.0/* /usr/local/redis [root@redis_master redis]# cd /usr/local/redis [root@redis_master redis]# make [root@redis_master src]# cd src && make install [root@redis_master src]# cd /usr/local/redis [root@redis_master redis]# cp redis.conf /etc/ [root@redis_master redis]# mkdir -p /redis/log #日志目录 [root@redis_master redis]# mkdir -p /redis/run #pid文件目录 [root@redis_master redis]# mkdir -p /redis/data #本地快照数据库存放目录 [root@redis_master redis]# vi /etc/redis.conf #编辑 daemonize yes #设置后台启动redis [root@redis_master redis]# sysctl vm.overcommit_memory=1 [root@redis_master redis]# echo never > /sys/kernel/mm/transparent_hugepage/enabled [root@redis_master redis]# vi /etc/sysctl.conf #编辑，在最后一行添加下面代码 vm.overcommit_memory = 1 [root@redis_master redis]# sysctl -p #使设置立即生效
3.设置redis开机自动启动
vi /etc/init.d/redis #编辑，添加以下代码
#!/bin/sh
# chkconfig: 2345 90 10
# description: Redis is a persistent key-value database
# redis Startup script for redis processe
# processname: redis
redis_path="/usr/local/bin/redis-server"
redis_conf="/etc/redis.conf"
redis_pid="/redis/run/redis.pid"
# Source function library.
. /etc/rc.d/init.d/functions
[ -x $redis_path ] || exit 0
RETVAL=0
prog="redis"
# Start daemons.
start() {
if [ -e $redis_pid -a ! -z $redis_pid ];then
echo $prog" already running...."
exit 1
fi
echo -n $"Starting $prog "
# Single instance for all caches
$redis_path $redis_conf
RETVAL=$?
[ $RETVAL -eq 0 ] && {
touch /var/lock/subsys/$prog
success $"$prog"
}
echo
return $RETVAL
}
# Stop daemons.
stop() {
echo -n $"Stopping $prog "
killproc -d 10 $redis_path
echo
[ $RETVAL = 0 ] && rm -f $redis_pid /var/lock/subsys/$prog
RETVAL=$?
return $RETVAL
}
# See how we were called.
case "$1" in
start)
start
;;
stop)
stop
;;
status)
status $prog
RETVAL=$?
;;
restart)
stop
start
;;
condrestart)
if test "x`pidof redis`" != x; then
stop
start
fi
;;
*)
echo $"Usage: $0 {start|stop|status|restart|condrestart}"
exit 1
esac
exit $RETVAL
[root@redis_master redis]# chmod 755 /etc/init.d/redis #添加脚本执行权限 [root@redis_master redis]# chkconfig --add redis #添加开启启动 [root@redis_master redis]# chkconfig --level 2345 redis on #设置启动级别 [root@redis_master redis]# chkconfig --list redis #查看启动级别 [root@redis_master redis]# service redis restart #重新启动redis Stopping redis [ OK ] Starting redis [ OK ]
4.redis主从配置文件
redis_master配置文件
[root@redis_master redis]# vim /etc/redis.conf protected-mode no #必须要加的参数，在3.2版本 daemonize yes pidfile /redis/run/redis.pid port 6379 tcp-backlog 511 timeout 1800 tcp-keepalive 0 loglevel verbose logfile "/redis/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 ./ slaveof 192.168.155.206 6379 slave-read-only yes 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
redis_slave配置文件
[root@redis_slave redis]# vim /etc/redis.conf protected-mode no #必须要加的参数，在3.2版本 daemonize yes pidfile /redis/run/redis.pid port 6379 tcp-backlog 511 timeout 1800 tcp-keepalive 0 loglevel verbose logfile "/redis/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 ./ slaveof 192.168.155.205 6379 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
然后重启redis，现在redis都配置了双主，但是他们现在都不可以写入，必须要配置keepalived，有redis主，才可以写入。
小提示：经过最后面的测试，redis.conf配置文件，可以省略2个配置文件不写，也可以测试成功，配置如下：
slaveof 192.168.155.206 6379 slave-read-only yes
5.redis配置文件详解
daemonize yes #以后台daemon方式运行redis pidfile "/var/run/redis.pid" #redis以后台运行，默认pid文件路径/var/run/redis.pid port 6379 #默认端口 bind 127.0.0.1 #默认绑定本机所有ip地址，为了安全，可以只监听内网ip timeout 300 #客户端空闲n秒后断开连接,单位为秒；默认是 0 表示不断开 loglevel verbose #设置日志级别，支持四个级别：debug、notice、verbose、warning logfile stdout #日志记录方式，默认为标准输出，logs不写文件，输出到空设备/deb/null logfile "/redis/log/redis.log" #可以指定日志文件路径 databases 16 #开启数据库的数量 save 900 1 save 300 10 save 60 10000 创建本地数据库快照，格式：save * * 900秒内，执行1次写操作 300秒内，执行10次写操作 60秒内，执行10000次写操作 rdbcompression yes #启用数据库lzf压缩，也可以设置为no dbfilename dump.rdb #本地快照数据库名称 dir "/redis/6369/" #本地快照数据库存放目录 requirepass 123456 #设置redis数据库连接密码 maxclients 10000 #同一时间最大客户端连接数，0为无限制 maxmemory 1024MB #设定redis最大使用内存，值要小于物理内存，必须设置 appendonly yes #开启日志记录，相当于MySQL的binlog appendfilename "appendonly.aof" #日志文件名，注意：不是目录路径 appendfsync everysec #每秒执行同步，还有两个参数always、no一般设置为everysec，相当于MySQL事物日志的写方式 slave-serve-stale-data yes #当主master服务器挂机或主从复制在进行时，是否依然可以允许客户访问可能过期的数据。 #在"yes"情况下,slave继续向客户端提供只读服务,有可能此时的数据已经过期； #在"no"情况下，任何向此server发送的数据请求服务(包括客户端和此server的slave)都将被告知"error" slave-read-only yes #slave是否为"只读"，强烈建议为"yes" repl-ping-slave-period 10 #slave向指定的master发送ping消息的时间间隔(秒)，默认为10 repl-timeout 60 #slave与master通讯中,最大空闲时间,默认60秒.超时将导致连接关闭 repl-disable-tcp-nodelay no #slave与master的连接,是否禁用TCP nodelay选项。"yes"表示禁用 #那么socket通讯中数据将会以packet方式发送(packet大小受到socket buffer限制)。
1. Redis默认不是以守护进程的方式运行，可以通过该配置项修改，使用yes启用守护进程 daemonize no 2. 当Redis以守护进程方式运行时，Redis默认会把pid写入/var/run/redis.pid文件，可以通过pidfile指定 pidfile /var/run/redis.pid 3. 指定Redis监听端口，默认端口为6379，作者在自己的一篇博文中解释了为什么选用6379作为默认端口， 因为6379在手机按键上MERZ对应的号码，而MERZ取自意大利歌女Alessia Merz的名字 port 6379 4. 绑定的主机地址 bind 127.0.0.1 5.当 客户端闲置多长时间后关闭连接，如果指定为0，表示关闭该功能 timeout 300 6. 指定日志记录级别，Redis总共支持四个级别：debug、verbose、notice、warning，默认为verbose loglevel verbose 7. 日志记录方式，默认为标准输出，如果配置Redis为守护进程方式运行， 而这里又配置为日志记录方式为标准输出，则日志将会发送给/dev/null logfile stdout 8. 设置数据库的数量，默认数据库为0，可以使用SELECT <dbid>命令在连接上指定数据库id databases 16 9. 指定在多长时间内，有多少次更新操作，就将数据同步到数据文件，可以多个条件配合 save <seconds> <changes> Redis默认配置文件中提供了三个条件： save 900 1 save 300 10 save 60 10000 分别表示900秒（15分钟）内有1个更改，300秒（5分钟）内有10个更改以及60秒内有10000个更改。 10. 指定存储至本地数据库时是否压缩数据，默认为yes，Redis采用LZF压缩，如果为了节省CPU时间， 可以关闭该选项，但会导致数据库文件变的巨大 rdbcompression yes 11. 指定本地数据库文件名，默认值为dump.rdb dbfilename dump.rdb 12. 指定本地数据库存放目录 dir ./ 13. 设置当本机为slav服务时，设置master服务的IP地址及端口，在Redis启动时， 它会自动从master进行数据同步 slaveof <masterip> <masterport> 14. 当master服务设置了密码保护时，slav服务连接master的密码 masterauth <master-password> 15. 设置Redis连接密码，如果配置了连接密码，客户端在连接Redis时需要通过AUTH <password>命令提供密码，默认关闭 requirepass foobared 16. 设置同一时间最大客户端连接数，默认无限制，Redis可以同时打开的客户端连接数为Redis进程可以打开的最大文件描述符数， 如果设置 maxclients 0，表示不作限制。当客户端连接数到达限制时， Redis会关闭新的连接并向客户端返回max number of clients reached错误信息 maxclients 128 17. 指定Redis最大内存限制，Redis在启动时会把数据加载到内存中，达到最大内存后，Redis会先尝试清除已到期或即将到期的Key， 当此方法处理 后，仍然到达最大内存设置，将无法再进行写入操作，但仍然可以进行读取操作。 Redis新的vm机制，会把Key存放内存，Value会存放在swap区 maxmemory <bytes> 18. 指定是否在每次更新操作后进行日志记录，Redis在默认情况下是异步的把数据写入磁盘，如果不开启， 可能会在断电时导致一段时间内的数据丢失。因为 redis本身同步数据文件是按上面save条件来同步的， 所以有的数据会在一段时间内只存在于内存中。默认为no appendonly no 19. 指定更新日志文件名，默认为appendonly.aof appendfilename appendonly.aof 20. 指定更新日志条件，共有3个可选值： no：表示等操作系统进行数据缓存同步到磁盘（快） always：表示每次更新操作后手动调用fsync()将数据写到磁盘（慢，安全） everysec：表示每秒同步一次（折衷，默认值）
6.keepalived安装（两台机器都同时安装）
[root@redis_master ~]# wget http://www.keepalived.org/software/keepalived-1.2.20.tar.gz [root@redis_master ~]# tar -xf keepalived-1.2.20.tar.gz [root@redis_master ~]# cd keepalived-1.2.20 [root@redis_master keepalived-1.2.20]# ./configure --prefix=/usr/local/keepalived [root@redis_master keepalived-1.2.20]# make && make install [root@redis_master keepalived-1.2.20]# cp /usr/local/keepalived/sbin/keepalived /usr/sbin/ [root@redis_master keepalived-1.2.20]# cp /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/ [root@redis_master keepalived-1.2.20]# cp /usr/local/keepalived/etc/rc.d/init.d/keepalived /etc/init.d/ [root@redis_master keepalived-1.2.20]# cp /usr/local/keepalived/etc/keepalived/keepalived.conf /etc/keepalived/ [root@redis_master keepalived-1.2.20]# mkdir -p /etc/keepalived/log/ [root@redis_master keepalived-1.2.20]# mkdir -p /etc/keepalived/scripts/ 添加日志 [root@redis_master keepalived-1.2.20]# vim /etc/sysconfig/keepalived KEEPALIVED_OPTIONS="-D" 修改为 KEEPALIVED_OPTIONS="-D -d -S 0" [root@redis_master keepalived-1.2.20]# vi /etc/rsyslog.conf 加入如下配置： #keepalived -S 0 local0.* /var/log/keepalived.log 重启日志服务 [root@redis_master keepalived-1.2.20]# /etc/init.d/rsyslog restart 监测日志文件是否生成 [root@redis_master keepalived-1.2.20]# ll /var/log/keepalived.log -rw-------. 1 root root 0 Jun 21 19:46 /var/log/keepalived.log keepalived已经安装完毕
7.keepalived配置文件
redis主上keepalived配置文件
global_defs {
lvs_id LVS_redis 80
smtp_connect_timeout 30
}
vrrp_script chk_redis {
script "sh /etc/keepalived/scripts/redis_check.sh"
interval 1
weight 2
}
vrrp_instance VI_1 {
state MASTER
interface eth1
virtual_router_id 60
unicast_src_ip 192.168.155.205
unicast_peer {
192.168.155.206
}
priority 200
advert_int 1
track_script {
chk_redis
}
virtual_ipaddress {
192.168.155.207
}
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
}
redis从上keepalived配置文件
global_defs {
lvs_id LVS_redis 80
smtp_connect_timeout 30
}
vrrp_script chk_redis {
script "sh /etc/keepalived/scripts/redis_check.sh"
interval 1
weight 2
}
vrrp_instance VI_1 {
state MASTER
interface eth1
virtual_router_id 60
priority 200
unicast_src_ip 192.168.155.206
unicast_peer {
192.168.155.205
}
advert_int 1
track_script {
chk_redis
}
virtual_ipaddress {
192.168.155.207
}
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
}
以上是keepalived配置文件。
redis_master
redis_check.sh文件如下：
#!/bin/bash
SERV=keepalived
CHECK_TIME=2
check() {
/usr/local/bin/redis-cli ping > /dev/null 2>&1
ret=$?
if [ $ret -ne 0 ];then
return $ret;
fi
}
while [ $CHECK_TIME -ne 0 ];do
let "CHECK_TIME -= 1"
check
REDIS_OK=$?
if [ $REDIS_OK -eq 0 ];then
exit $REDIS_OK
else
if [ $CHECK_TIME -eq 0 ];then
/etc/init.d/$SERV stop
exit $REDIS_OK
fi
fi
done
redis_stop.sh文件如下： #!/bin/bash ###/etc/keepalived/scripts/redis_stop.sh REDISCLI="/usr/local/bin/redis-cli " LOGFILE="/etc/keepalived/log/redis-state.log" pid=$$ echo "Run redis_stop.sh" >> $LOGFILE echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[master]" >> $LOGFILE echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[master] Being slave state..." >> $LOGFILE 2>&1 echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[slaver] Run 'SLAVEOF 192.168.155.206 6379'" >> $LOGFILE $REDISCLI SLAVEOF 192.168.155.206 6379 >> $LOGFILE 2>&1 echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[slaver] slave connect to 192.168.155.206 ok..." >> $LOGFILE
redis_fault.sh文件如下： #!/bin/bash ###/etc/keepalived/scripts/redis_fault.sh REDISCLI="/usr/local/bin/redis-cli " LOGFILE="/etc/keepalived/log/redis-state.log" pid=$$ echo "Run redis_fault.sh" >> $LOGFILE echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[master]" >> $LOGFILE echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[master] Being slave state..." >> $LOGFILE 2>&1 echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[slaver] Run 'SLAVEOF 192.168.155.206 6379'" >> $LOGFILE $REDISCLI SLAVEOF 192.168.155.206 6379 >> $LOGFILE 2>&1 echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[slaver] slave connect to 192.168.155.206 ok..." >> $LOGFILE
redis_backup.sh文件如下： #!/bin/bash ###/etc/keepalived/scripts/redis_backup.sh REDISCLI="/usr/local/bin/redis-cli " LOGFILE="/etc/keepalived/log/redis-state.log" pid=$$ echo "Run redis_backup.sh" >> $LOGFILE echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[master]" >> $LOGFILE echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[master] Being slave state..." >> $LOGFILE 2>&1 echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[slaver] Run 'SLAVEOF 192.168.155.206 6379'" >> $LOGFILE $REDISCLI SLAVEOF 192.168.155.206 6379 >> $LOGFILE 2>&1 echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[slaver] slave connect to 192.168.155.206 ok..." >> $LOGFILE
redis_master.sh文件如下： #!/bin/bash ###/etc/keepalived/scripts/redis_master.sh REDISCLI="/usr/local/bin/redis-cli " LOGFILE="/etc/keepalived/log/redis-state.log" pid=$$ echo "Run redis_master.sh" >> $LOGFILE echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[slaver]" >> $LOGFILE echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[slaver] Run 'SLAVEOF 192.168.88.206 6379'" >> $LOGFILE $REDISCLI SLAVEOF 192.168.155.206 6379 >> $LOGFILE 2>&1 echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[master] Run slaveof no one,close master/slave" >> $LOGFILE $REDISCLI SLAVEOF NO ONE >> $LOGFILE 2>&1 echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[master] wait other slave connect...." >> $LOGFILE
redis_slave
redis_check.sh文件如下：
#!/bin/bash
SERV=keepalived
CHECK_TIME=2
check() {
/usr/local/bin/redis-cli ping > /dev/null 2>&1
ret=$?
if [ $ret -ne 0 ];then
return $ret;
fi
}
while [ $CHECK_TIME -ne 0 ];do
let "CHECK_TIME -= 1"
check
REDIS_OK=$?
if [ $REDIS_OK -eq 0 ];then
exit $REDIS_OK
else
if [ $CHECK_TIME -eq 0 ];then
/etc/init.d/$SERV stop
exit $REDIS_OK
fi
fi
done
redis_stop.sh文件如下： #!/bin/bash ###/etc/keepalived/scripts/redis_stop.sh REDISCLI="/usr/local/bin/redis-cli " LOGFILE="/etc/keepalived/log/redis-state.log" pid=$$ echo "Run redis_stop.sh" >> $LOGFILE echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[master]" >> $LOGFILE echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[master] Being slave state..." >> $LOGFILE 2>&1 echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[slaver] Run 'SLAVEOF 192.168.155.205 6379'" >> $LOGFILE $REDISCLI SLAVEOF 192.168.155.205 6379 >> $LOGFILE 2>&1 echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[slaver] slave connect to 192.168.155.205 ok..." >> $LOGFILE
redis_fault.sh文件如下： #!/bin/bash ###/etc/keepalived/scripts/redis_fault.sh REDISCLI="/usr/local/bin/redis-cli " LOGFILE="/etc/keepalived/log/redis-state.log" pid=$$ echo "Run redis_fault.sh" >> $LOGFILE echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[master]" >> $LOGFILE echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[master] Being slave state..." >> $LOGFILE 2>&1 echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[slaver] Run 'SLAVEOF 192.168.155.205 6379'" >> $LOGFILE $REDISCLI SLAVEOF 192.168.155.205 6379 >> $LOGFILE 2>&1 echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[slaver] slave connect to 192.168.155.205 ok..." >> $LOGFILE
redis_backup.sh文件如下： #!/bin/bash ###/etc/keepalived/scripts/redis_backup.sh REDISCLI="/usr/local/bin/redis-cli " LOGFILE="/etc/keepalived/log/redis-state.log" pid=$$ echo "Run redis_backup.sh" >> $LOGFILE echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[master]" >> $LOGFILE echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[master] Being slave state..." >> $LOGFILE 2>&1 echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[slaver] Run 'SLAVEOF 192.168.155.205 6379'" >> $LOGFILE $REDISCLI SLAVEOF 192.168.155.205 6379 >> $LOGFILE 2>&1 echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[slaver] slave connect to 192.168.155.205 ok..." >> $LOGFILE
redis_master.sh文件如下： #!/bin/bash ###/etc/keepalived/scripts/redis_master.sh REDISCLI="/usr/local/bin/redis-cli " LOGFILE="/etc/keepalived/log/redis-state.log" pid=$$ echo "Run redis_master.sh" >> $LOGFILE echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[slaver]" >> $LOGFILE echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[slaver] Run 'SLAVEOF 192.168.88.205 6379'" >> $LOGFILE $REDISCLI SLAVEOF 192.168.155.205 6379 >> $LOGFILE 2>&1 echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[master] Run slaveof no one,close master/slave" >> $LOGFILE $REDISCLI SLAVEOF NO ONE >> $LOGFILE 2>&1 echo "`date +'%Y-%m-%d:%H:%M:%S'`|$pid|state:[master] wait other slave connect...." >> $LOGFILE
[root@redis_master scripts]# cd /etc/keepalived/scripts/ [root@redis_master scripts]# chmod +x * [root@redis_master scripts]# /etc/init.d/keepalivded restart
测试阶段：
1. redis主从都启动keepalived
redis_master [root@redis_master scripts]# ip a 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000 link/ether 00:0c:29:d6:63:b6 brd ff:ff:ff:ff:ff:ff inet 192.168.155.205/24 brd 192.168.155.255 scope global eth1 inet 192.168.155.207/32 scope global eth1 inet6 fe80::20c:29ff:fed6:63b6/64 scope link valid_lft forever preferred_lft forever
redis_slave [root@redis_slave scripts]# ip a 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000 link/ether 00:0c:29:46:38:94 brd ff:ff:ff:ff:ff:ff inet 192.168.155.206/24 brd 192.168.155.255 scope global eth1 inet6 fe80::20c:29ff:fe46:3894/64 scope link valid_lft forever preferred_lft forever
2. 测试主从同步
redis_master [root@redis_master scripts]# redis-cli 127.0.0.1:6379> set laopo hyl OK 127.0.0.1:6379> get laopo "hyl" 127.0.0.1:6379>
redis_slave [root@redis_slave ~]# redis-cli 127.0.0.1:6379> get laopo "hyl" 127.0.0.1:6379>
redis主从已经测试成功
可以多设置几个值（在down之前）：
127.0.0.1:6379> set 11 22 OK 127.0.0.1:6379> set 22 33 OK 127.0.0.1:6379> set 33 44 OK 127.0.0.1:6379> set 44 55 OK 127.0.0.1:6379> get 11 "22" 127.0.0.1:6379> get 22 "33" 127.0.0.1:6379> get 33 "44" 127.0.0.1:6379> get 44 "55"
3.测试redis主down
redis_master [root@redis_master ~]# /etc/init.d/redis stop [root@redis_master ~]# ip a 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000 link/ether 00:0c:29:d6:63:b6 brd ff:ff:ff:ff:ff:ff inet 192.168.155.205/24 brd 192.168.155.255 scope global eth1 inet6 fe80::20c:29ff:fed6:63b6/64 scope link valid_lft forever preferred_lft forever [root@redis_master ~]# ss -ln State Recv-Q Send-Q Local Address:Port Peer Address:Port LISTEN 0 128 :::22 :::* LISTEN 0 128 *:22 *:* LISTEN 0 100 ::1:25 :::* LISTEN 0 100 127.0.0.1:25 *:* LISTEN 0 50 *:3306 *:*
redis_slave [root@redis_slave ~]# ip a 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000 link/ether 00:0c:29:46:38:94 brd ff:ff:ff:ff:ff:ff inet 192.168.155.206/24 brd 192.168.155.255 scope global eth1 inet 192.168.155.207/32 scope global eth1 inet6 fe80::20c:29ff:fe46:3894/64 scope link valid_lft forever preferred_lft forever [root@redis_slave ~]# ss -ln State Recv-Q Send-Q Local Address:Port Peer Address:Port LISTEN 0 128 :::22 :::* LISTEN 0 128 *:22 *:* LISTEN 0 100 ::1:25 :::* LISTEN 0 100 127.0.0.1:25 *:* LISTEN 0 50 *:3306 *:* LISTEN 0 128 *:6379 *:* LISTEN 0 128 :::6379 :::*
vip已经漂移至 redis_slave，测试redis主从是否切换；
redis_slave [root@redis_slave ~]# redis-cli 127.0.0.1:6379> set 123 123 OK 127.0.0.1:6379> get 123 "123" 127.0.0.1:6379> get 11 "22" 127.0.0.1:6379> get 22 "33" 127.0.0.1:6379> get 33 "44" 再down之前，多设置几个键值 127.0.0.1:6379> set 1010 1010 OK 127.0.0.1:6379> set 2020 2020 OK 127.0.0.1:6379> set 3030 3030 OK 127.0.0.1:6379> get 1010 "1010" 127.0.0.1:6379> get 2020 "2020" 127.0.0.1:6379> get 3030 "3030"
redis_master [root@redis_master ~]# /etc/init.d/redis start [root@redis_master ~]# /etc/init.d/keepalived start Starting keepalived: [ OK ] [root@redis_master ~]# redis-cli 127.0.0.1:6379> get 123 "123" 127.0.0.1:6379> get 11 "22" 127.0.0.1:6379> get 33 "44" 127.0.0.1:6379> get 44 "55" 127.0.0.1:6379> get 1010 "1010" 127.0.0.1:6379> get 2020 "2020" 127.0.0.1:6379> get 3030 "3030"
redis数据不会丢失，redis从立马会接管vip提供服务。redis主从角色互调。
4.redis主恢复后，一直处于slave状态，如果redis从down掉，redis主是否会重新夺取vip，并且数据自动同步回来。
redis_slave [root@redis_slave ~]# /etc/init.d/redis stop [root@redis_slave ~]# /etc/init.d/redis start [root@redis_slave ~]# /etc/init.d/keepalived start Starting keepalived: [ OK ] [root@redis_slave ~]# i a bash: i: command not found [root@redis_slave ~]# ip a 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000 link/ether 00:0c:29:46:38:94 brd ff:ff:ff:ff:ff:ff inet 192.168.155.206/24 brd 192.168.155.255 scope global eth1 inet6 fe80::20c:29ff:fe46:3894/64 scope link valid_lft forever preferred_lft forever vip已经漂移至redis_master
redis_master [root@redis_master ~]# ip a 1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00 inet 127.0.0.1/8 scope host lo inet6 ::1/128 scope host valid_lft forever preferred_lft forever 2: eth1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000 link/ether 00:0c:29:d6:63:b6 brd ff:ff:ff:ff:ff:ff inet 192.168.155.205/24 brd 192.168.155.255 scope global eth1 inet 192.168.155.207/32 scope global eth1 inet6 fe80::20c:29ff:fed6:63b6/64 scope link valid_lft forever preferred_lft forever vip又重新绑定在redis_master主上
测试现在redis主从是否同步数据，和之前的数据是否存在；
redis_master [root@redis_master ~]# redis-cli 127.0.0.1:6379> set last 111 OK 127.0.0.1:6379> get last "111" 127.0.0.1:6379> get 1010 "1010" 127.0.0.1:6379> get 2020 "2020" 127.0.0.1:6379> get 11 "22" 127.0.0.1:6379> get 22 "33" 127.0.0.1:6379> get 33 "44"
redis_slave [root@redis_slave ~]# redis-cli 127.0.0.1:6379> get last "111" 127.0.0.1:6379> get 11 "22" 127.0.0.1:6379> get 22 "33" 127.0.0.1:6379> get 123 "123" 127.0.0.1:6379> get 1010 "1010" 127.0.0.1:6379> get 2020 "2020" 127.0.0.1:6379>
数据不会丢失，全部都同步上。
redis+keepalived 主主模型，其实redis现在不支持主主，只是我们可以理解为redis主主。可以很智能的自动切换，redis主从。主要2台redis不同时挂掉，就不会丢失数据及对数据造成影响。
此方案，已经在线上使用，大家可以参考下文档。
原创文章，作者：Net20_赤羽，如若转载，请注明出处：http://www.178linux.com/19183
