Redis 主从切换+Predixy

部署环境

主机名	ip
redis-zhu	192.168.244.132
redis-cong	192.168.244.128

1.配置互信

两台主机都做
通过ssh-keygen 生成公钥私钥对，拷贝到兄弟节点； 
ssh-keygen
ssh-copy ip

2.Redis 包安装及账号设置

安装Redis 包如低版本，可以直接官网下载rpm 包进行安装，会直接生成Redis 账号及组；
如较新版本需要下载源码tar.gz,解压后自行编译，同时需要手动添加Redis
安装依赖
yum -y install gcc gcc-c++ tcl
账号及组;
groupadd redis
useradd -s /sbin/nologin  -g redis redis
Redis 下载到/opt下:
wget http://download.redis.io/releases/redis-5.0.8.tar.gz
tar -xzf redis-5.0.8.tar.gz
cd redis-5.0.8
make & make install
复制配置文件到/etc
cp /opt/redis-5.0.8/redix.conf /etc
cp /opt/redis-5.0.8/sentinel.conf /etc

系统 及 Redis参数配置

系统 :

vi /etc/rc.local
echo never > /sys/kernel/mm/transparent_hugepage/enabled
echo never > /sys/kernel/mm/transparent_hugepage/defrag
echo 4096 > /proc/sys/net/core/somaxconn

vi /etc/sysctl.conf
vm.overcommit_memory = 1
net.core.somaxconn = 4096
sysctl -p

ulimit -SHn 100000

vi /etc/security/limits.conf

* soft nofile 100000
* hard nofile 100000
* soft nproc  64000
* hard nproc  64000

Redis: 参数配置

vim /etc/redix.conf
requirepass "wxIMtMRWw7104MSLitiowI4QCknkzFMV" #主上配置
masterauth "wxIMtMRWw7104MSLitiowI4QCknkzFMV"  #从上配置
bind 0.0.0.0
port 6380
maxmemory 3gb
dir "/redis/data"
save 900 1
save 300 10
save 60 10000
stop-writes-on-bgsave-error no
tcp-backlog 511
timeout 0
tcp-keepalive 300
pidfile "/var/run/redis.pid"
logfile "/var/log/redis/redis.log"

sentinel 配置：

vim /etc/sentinle.conf  #主配置
port 26380
daemonize yes
pidfile "/var/run/redis-sentinel.pid"
logfile "/opt/redis/data/sentinel.log"
dir "/tmp"
sentinel deny-scripts-reconfig yes
sentinel monitor mymaster 192.168.244.132 6380 1
sentinel config-epoch mymaster 5
sentinel leader-epoch mymaster 5
protected-mode no
sentinel current-epoch 5

++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++

vim /etc/sentinle.conf #从配置   
port 26380
daemonize yes
pidfile "/var/run/redis-sentinel.pid"
logfile "/opt/redis5/data/sentinel.log"
dir "/tmp"
sentinel deny-scripts-reconfig yes
sentinel monitor mymaster 192.168.244.132 6380 1
sentinel config-epoch mymaster 5
sentinel leader-epoch mymaster 5
protected-mode no
sentinel current-epoch 5

4.predixy 安装

同Redis ,可以直接下载编译后执行文件或是下载源码编译；配置文件拷贝到固定目录；
安装依赖
yum install libstdc++-static -y
下载predixy 
git clone https://github.com/joyieldInc/predixy.git
cd predixy
编译既可以
make
cp 执行文件到bin目录   
cp src/predixy /usr/local/bin/
cp配置文件到/etc/predixy（目录需要创建）
cp predixy/conf/* /etc/predixy/

5. 配置Predixy

vim /etc/predixy/auth.conf
Authority {
    Auth {
        Mode write
    }
    Auth {
        Mode admin
    }
}


vim  /etc/predixy/predixy.conf
Name PredixyExample
WorkerThreads 1
ClientTimeout 300
LogVerbSample 0
LogDebugSample 0
LogInfoSample 10000
LogNoticeSample 1
LogWarnSample 1
LogErrorSample 1
Include auth.conf
Include sentinel.conf
Include latency.conf





vim /etc/predixy/sentinel.conf  
SentinelServerPool {
	    Pssword wxIMtMRWw7104MSLitiowI4QCknkzFMV
        Databases 16
        Hash crc16
        HashTag {}
        Distribution modula
        MasterReadPriority 60
        StaticSlaveReadPriority 50
        DynamicSlaveReadPriority 50
        RefreshInterval 1
        ServerTimeout 1
        ServerFailureLimit 1
        ServerRetryTimeout 1
        KeepAlive 120
        Sentinels {
           + 192.168.244.132:26380
           + 192.168.244.128:26380
        }
        Group mymaster {
          + 192.168.244.132:6380
          + 192.168.244.128:6380
        }
}




MasterReadPriority: 读写分离功能，从redis master节点执行读请求的优先级，为0则禁止读redis master，不指定的话为50StaticSlaveReadPriority: 读写分离功能，从静态redis slave节点执行读请求的优先级，所谓静态节点，是指在本配置文件中显示列出的redis节点，不指定的话为0


MasterReadPriority，StaticSlaveReadPriority，DynamicSlaveReadPriority这三个参数都配成一样，就相当于负载均衡

ServerFailureLimit: 一个redis实例出现多少次才错误以后将其标记为失效，不指定的话为10ServerRetryTimeout: 一个redis实例失效后多久后去检查其是否恢复正常，不指定的话为1秒

6.keepalived 安装

可以直接下载rpm,并进行安装；
yum  -y install keepalived

7.配置Keepalived

vim /etc/keepalived/keepalived.conf #主上配置
global_defs {
       notification_email {
              root@localhost
        }
        notification_email_from keepalived@localhost
        smtp_server 127.0.0.1
        smtp_connect_timeout 30 
        router_id redis-zhu
        vrrp_mcast_group4 224.0.100.100
      }       
vrrp_script check_redis_proxy {
      script "/usr/bin/check_redis_proxy.sh"
       interval 3
       weight 2
  }
  
  vrrp_instance VI_1 {
      state MASTER 
      interface eno16777736 
      virtual_router_id 6
      priority 100 
      advert_int 1 
      authentication {
          auth_type PASS 
          auth_pass 571f97b2
      }
     track_script {
         check_redis_proxy
     }
      virtual_ipaddress {
          192.168.244.144/24
      }
  }

vim /etc/keepalived/keepalived.conf #从上配置
global_defs {
       notification_email {
              root@localhost
        }
        notification_email_from keepalived@localhost
        smtp_server 127.0.0.1
        smtp_connect_timeout 30 
        router_id redis-zhu
        vrrp_mcast_group4 224.0.100.100
      }       
vrrp_script check_redis_proxy {
      script "/usr/bin/check_redis_proxy.sh"
       interval 3
       weight 2
  }
  
  vrrp_instance VI_1 {
      state BADKUP 
      interface ens33 
      virtual_router_id 6
      priority 80 
      advert_int 1 
      authentication {
          auth_type PASS 
          auth_pass 571f97b2
      }
     track_script {
         check_redis_proxy
     }
      virtual_ipaddress {
          192.168.244.144/24
      }
  }

8. Keepalived 脚本

vim /usr/bin/check_redis_proxy.sh
#!/bin/bash

PREDIXY_PID=`ps -ef |grep predixy|grep -v 'grep'|wc -l`
ps -ef |grep predixy|grep -v 'grep'|wc -l
if [ "${PREDIXY_PID}" -ge 1 ];then
	echo "predixy is Ok"
else
	systemctl start predixy
	sleep 3;
	PREDIXY_PID2=`ps -ef |grep predixy|grep -v 'grep'|wc -l`
         if  [ "${PREDIXY_PID2}" -eq 0 ];then
		systemctl stop keepalived
         fi
		
fi

9. Service 文件供参考

cat /usr/lib/systemd/system/redis.service
[Unit] 
Description=Redis
After=syslog.target nework.target

[Service]
ExecStart=/usr/bin/redis-server /etc/redis.conf  
ExecStop=/usr/bin/pkill redis-server
TimeoutStopSec=0
Restart=on-failure
User=redis
Group=redis
RuntimeDirectory=redis
RuntimeDirectoryMode=0755

# file size
LimitFSIZE=infinity
# cpu time
LimitCPU=infinity
# Virtual memory size
LimitAS=infinity
# open files
LimitNOFILE=64000
# processes/threads
LimitNPROC=64000
# stack size
LimitSTACK=1048576
# locked memory
LimitMEMLOCK=infinity
# total threads(user+kernel)
TasksMax=infinity
TasksAccounting=false
[Install]
WantedBy=multi-user.target

cat /usr/lib/systemd/system/redis-sentinel.service
[Unit]
Description=Redis-sentinel
After=syslog.target nework.target

[Service]
Type=forking
ExecStart=/usr/bin/redis-sentinel /etc/sentinel.conf  
ExecStop=/usr/bin/pkill redis-sentinel
TimeoutStopSec=0
Restart=on-failure
User=redis
Group=redis
RuntimeDirectory=redis
RuntimeDirectoryMode=0755

# file sizes
LimitFSIZE=infinity
# cpu time
LimitCPU=infinity
# virtual memory size
LimitAS=infinity
# open files
LimitNOFILE=64000
# processes/threads
LimitNPROC=64000
# stack size
LimitSTACK=1048576
# lcoked memory
LimitMEMLOCK=infinity
# total threads
TasksMax=infinity
TasksAccounting=false
[Install]
WantedBy=multi-user.target

cat  /usr/lib/systemd/system/predixy.service
[Unit]
Description=Predixy
After=syslog.target nework.target

[Service]
Type=simple
ExecStart=/usr/local/bin/predixy /etc/predixy/predixy.conf
ExecReload=/bin/kill -USR2 $MAINPID
ExecStop=/bin/kill -SIGINT $MAINPID
PrivateTmp=true

TimeoutStopSec=0
Restart=on-failure
User=redis
Group=redis
RuntimeDirectory=redis
RuntimeDirectory=0755

# file size
LimitFSIZE=infinity
# cpu time
LimitCPU=infinity
# virtual memory size
LimitAS=infinity
# open files
LimitNOFILE=64000
# processes/threads
LimitNPROC=64000
# stack size
LimitSTACK=1048576
# locked memory
LimitMEMLOCK=infinity
# total threads
TasksMax=infinity
TasksAccounting=false
[Install]
WantedBy=multi-user.target

10. 启动服务

依次启动并确认正常后，启动下一个Redis, Redis-Sentinel, Predixy, Keepalived; 
最后确认主从状态，代理状态，vip;

systemctl start keepalived
systemctl daemon-reload
systemctl enable redis.service predixy.service  sentinel.service keepalived.service
systemctl start  redis.service predixy.service  sentinel.service

注意以上两台主机都安装

Predixy 参考文档：https://github.com/joyieldInc/predixy/blob/master/doc/config_CN.md