Keepalived 2.0.9 + Redis5.0部署redis主从高可用
项目需要部署搭建redis主从高可用环境，对外使用VIP提供服务，以下是实现步骤：
Keepalived 实现VRRP（虚拟路由冗余）协议，从路由级别实现VIP切换，可以完全避免类似heartbeat脑裂问题，可以很好的实现主从、主备、互备方案。
实现切换逻辑如下：A和B两台机器
1）A 、B机器依次启动，A机作为主、B机为从。
2）主A挂掉，B接管业务并作为主。
3）A机起来，作为从SLAVEOF B。
4）B机挂掉，A机再切回主。在Keepalived 有两个角色：Master(一个)、Backup（多个），如果设置一个为Master，但Master挂了后再起来，必然再次业务又一次切换，这对于有状态服务是不可接受的。解决方案就是两台机器都设置为Backup，而且优先级高的Backup设置为nopreemt 不抢占主。
服务器环境：
192.168.255.198 VIP
192.168.255.64 redis-master 安装CentOS6.10 redis(5.0版本)、keepalived(2.0.9版本)
192.168.255.65 redis-slave 安装CentOS6.10 redis(5.0版本)、keepalived(2.0.9版本)部署开始，免去系统初始化、调优等步骤：
以下步骤两台机器都要安装：
1、安装redis5.0
cd /opt
wget http://download.redis.io/releases/redis-5.0.0.tar.gz
tar xvf redis-5.0.0.tar.gz
mv redis-5.0.0 /usr/local/redis
cd /usr/local/redis
make
ln -s /usr/local/redis/src/redis-cli /usr/bin/2、修改配置文件
bind 0.0.0.0
protected-mode yes
port 6380
tcp-backlog 511
timeout 0
tcp-keepalive 300
daemonize yes
supervised no
pidfile /var/run/redis_6380.pid
loglevel notice
logfile "/usr/local/redis/6380.log"
databases 16
always-show-logo yes
save 900 1
save 300 10
save 60 10000
stop-writes-on-bgsave-error yes
rdbcompression yes
rdbchecksum yes
dbfilename dump.rdb
dir /usr/local/redis/
replica-serve-stale-data yes
slaveof 192.168.255.65 6380 # slave机器设置为slaveof 192.168.255.64 6380
replica-read-only yes
repl-diskless-sync no
repl-diskless-sync-delay 5
repl-disable-tcp-nodelay no
replica-priority 100
maxclients 60000
maxmemory 30064771072
maxmemory-policy allkeys-lru
lazyfree-lazy-eviction no
lazyfree-lazy-expire no
lazyfree-lazy-server-del no
replica-lazy-flush no
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
aof-use-rdb-preamble 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-size -2
list-compress-depth 0
set-max-intset-entries 512
zset-max-ziplist-entries 128
zset-max-ziplist-value 64
hll-sparse-max-bytes 3000
stream-node-max-bytes 4096
stream-node-max-entries 100
activerehashing yes
client-output-buffer-limit normal 0 0 0
client-output-buffer-limit replica 256mb 64mb 60
client-output-buffer-limit pubsub 32mb 8mb 60
hz 10
dynamic-hz yes
aof-rewrite-incremental-fsync yes
rdb-save-incremental-fsync yes3、启动redis
/usr/local/redis/src/redis-server /usr/local/redis/redis.conf4、安装keepalived2.0.9 两台都安装
yum install popt popt-devel libnl libnl-devel libnfnetlink-devel -y #安装基础库文件
wget http://www.keepalived.org/software/keepalived-2.0.9.tar.gz
tar xvf keepalived-2.0.9.tar.gz
cd keepalived-2.0.9.tar.gz
./configure --prefix=/usr/local/keepalived --sbindir=/usr/local/keepalived/sbin
make && make install
ln -s /usr/local/sbin/keepalived /usr/sbin/
ln -s /usr/local/keepalived/etc/keepalived/ /etc/keepalived
cp /usr/local/keepalived/etc/sysconfig/keepalived /etc/sysconfig/Keepalived Master配置文件：
cat /etc/keepalived/keepalived.conf
! Configuration File for keepalived
global_defs {
router_id redis-master
}
vrrp_script chk_redis {
script "/usr/local/keepalived/scripts/redis_check.sh 127.0.0.1 6380" #监控脚本
interval 2 #监控时间
timeout 2 #超时时间
fall 3
}
vrrp_instance redis {
state BACKUP
interface em1
lvs_sync_daemon_interface em1
virtual_router_id 202
priority 150 #权重值
nopreempt #nopreempt：设置不抢占，这里只能设置在state为backup的节点上，而且这个节点的优先级必须比另外节点的高
advert_int 1
authentication { #all node must same
auth_type PASS #加密
auth_pass 1111 #密码
}
virtual_ipaddress {
192.168.255.189 #VIP地址
}
track_script {
chk_redis
}
notify_master "/usr/local/keepalived/scripts/redis_master.sh 127.0.0.1 192.168.255.64 6380"
notify_backup "/usr/local/keepalived/scripts/redis_backup.sh 127.0.0.1 192.168.255.65 6380"
notify_fault /usr/local/keepalived/scripts/redis_fault.sh
notify_stop /usr/local/keepalived/scripts/redis_stop.sh
}Keepalived Slave配置文件：
cat /etc/keepalived/keepalived.conf
! Configuration File for keepalived
global_defs {
router_id redis-slave
}
vrrp_script chk_redis{
script "/usr/local/keepalived/scripts/redis_check.sh 127.0.0.1 6380"
interval 2
timeout 2
fall 3
}
vrrp_instance redis {
state BACKUP
interface eth0
lvs_sync_daemon_interface eth0
virtual_router_id 202
priority 100
nopreempt
advert_int 1
authentication {
auth_type PASS
auth_pass 1111
}
virtual_ipaddress {
192.168.255.189
}
track_script {
chk_redis
}
notify_master "/usr/local/keepalived/scripts/redis_master.sh 127.0.0.1 192.168.255.64 6380"
notify_backup "/usr/local/keepalived/scripts/redis_backup.sh 127.0.0.1 192.168.255.65 6380"
notify_fault /usr/local/keepalived/scripts/redis_fault.sh
notify_stop /usr/local/keepalived/scripts/redis_stop.sh
}以上的keepalived.conf文件中的切换模式设置为nopreempt，意思是：
不抢占VIP资源，此种模式要是所有的节点都必须设置为state BACKUP模式
需要注意无论主备服务器都需要设置为BACKUP，与以往KeepAlived的配置不同，其目的就是防止主服务器恢复后重新抢回VIP，导致Redis切换从而影响稳定
创建脚本目录：
mkdir -p /usr/local/keepalived/scripts创建脚本文件：
vim /usr/local/keepalived/scripts/redis_backup.sh
#!/bin/bash
REDISCLI="/usr/local/redis/src/redis-cli"
LOGFILE="/var/log/keepalived-redis-state.log"
echo "[BACKUP]" >> $LOGFILE
date >> $LOGFILE
echo "Being slave...." >> $LOGFILE 2>&1
echo "Run SLAVEOF cmd ..." >> $LOGFILE 2>&1
$REDISCLI SLAVEOF $2 $3 >> $LOGFILE
sleep 100 #延迟100秒以后待数据同步完成后再取消同步状态
exit(0)
vim /usr/local/keepalived/scripts/redis_check.sh
#!/bin/bash
ALIVE=`/usr/local/redis/src/redis-cli -h $1 -p $2 PING`
LOGFILE="/var/log/keepalived-redis-check.log"
echo "[CHECK]" >> $LOGFILE
date >> $LOGFILE
if [ $ALIVE == "PONG" ]; then :
echo "Success: redis-cli -h $1 -p $2 PING $ALIVE" >> $LOGFILE 2>&1
exit 0
else
echo "Failed:redis-cli -h $1 -p $2 PING $ALIVE " >> $LOGFILE 2>&1
exit 1
fivim /usr/local/keepalived/scripts/redis_fault.sh
#!/bin/bash
LOGFILE="/var/log/keepalived-redis-state.log"
echo "[fault]" >> $LOGFILE
date >> $LOGFILEvim /usr/local/keepalived/scripts/redis_master.sh
#!/bin/bash
REDISCLI="/usr/local/redis/src/redis-cli -h $1 -p $3"
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 $2 $3 >> $LOGFILE 2>&1
#echo "SLAVEOF $2 cmd can't excute ... " >> $LOGFILE
sleep 10 #延迟10秒以后待数据同步完成后再取消同步状态
echo "Run SLAVEOF NO ONE cmd ..." >> $LOGFILE
$REDISCLI SLAVEOF NO ONE >> $LOGFILE 2>&1vim /usr/local/keepalived/scripts/redis_stop.sh
#!/bin/bash
LOGFILE="/var/log/keepalived-redis-state.log"
echo "[stop]" >> $LOGFILE
date >> $LOGFILE给脚本执行权限：
chmod +x /usr/local/keepalived/scripts/ -R脚本同步至slave：
scp -r scripts 192.168.255.65:/usr/local/keepalived/两台机器依次启动keepalived、redis：
/usr/local/keepalived/sbin/keepalived -D
/usr/local/redis/src/redis-server /usr/local/redis/redis.conf查看redis、keepalived进程是否启动
ps -ef | grep redis-server
root 2654 1 0 17:22 ? 00:00:05 /usr/local/redis/src/redis-server 0.0.0.0:6380
root 12140 2731 0 18:49 pts/0 00:00:00 grep redis-server
[root@sso-redis-a opt]# ps -ef | grep keep
root 2644 1 0 17:22 ? 00:00:00 /usr/local/keepalived/sbin/keepalived -D
root 2645 2644 0 17:22 ? 00:00:00 /usr/local/keepalived/sbin/keepalived -D
root 11987 2731 0 18:48 pts/0 00:00:00 grep keep将redis、keepalived服务加入开机启动
echo '/usr/local/keepalived/sbin/keepalived -D' >> /etc/rc.d/rc.local
echo '/usr/local/redis/src/redis-server /usr/local/redis/redis.conf' >> /etc/rc.d/rc.local
chmod +x /etc/rc.d/rc.local查看IP地址，VIP已经起来：
ip addr
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: em1: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq state UP qlen 1000
link/ether 14:18:77:52:28:11 brd ff:ff:ff:ff:ff:ff
inet 192.168.255.64/24 brd 192.168.255.255 scope global em1
inet 192.168.255.189/32 scope global em1
inet6 fe80::1618:77ff:fe52:2811/64 scope link
valid_lft forever preferred_lft forever查看redis状态
redis-cli -h 192.168.255.189.230 -p 6380 INFO|grep role
role:master
redis-cli -h 192.168.255.189.64 -p 6380 INFO|grep role
role:master
redis-cli -h 192.168.255.189.65 -p 6380 INFO|grep role
role:slave在master 64上set数据，65会有，主从生效
重启64机器，vip会在2秒内漂移到65上，同时65提升到master，在65插入数据，64服务器起来以后会自动同步。
依次类推，至此redis双机搭建完毕。
via: https://www.cnblogs.com/kevingrace/p/9001975.html
Tag标签:「redis keepalived 高可用」更新时间:「2021-11-04 17:16:40」阅读次数:「782」