redis-cluster部署

redis cluster: 自动，master+slave复制和读写分离，master+slave高可用和主备切换，支持多个master的hash slot支持数据分布式存储

2.在三台机器上启动6个redis实例

正式环境下，建议都是说在6台机器上去搭建，至少3台机器，保证，每个master都跟自己的slave不在同一台机器上，如果是6台自然更好，一个master+一个slave就死了

mkdir -p /etc/redis-cluster

mkdir -p /var/log/redis

mkdir -p /var/redis/7001

port 7001

cluster-enabled yes

cluster-config-file /etc/redis-cluster/node-7001.conf

cluster-node-timeout 15000

daemonize yes

pidfile /var/run/redis_7001.pid

dir /var/redis/7001

logfile /var/log/redis/7001.log

bind 192.168.31.187

appendonly yes

3.安装脚本

yum install -y ruby

yum install -y rubygems

gem install redis

如果出现ruby版本太低（通过https://www.jianshu.com/p/7a625eb8cde0进行升级）

cp /usr/local/redis-3.2.8/src/redis-trib.rb /usr/local/bin

redis-trib.rb create --replicas 1 192.168.31.187:7001 192.168.31.187:7002 192.168.31.19:7003 192.168.31.19:7004 192.168.31.227:7005 192.168.31.227:7006

redis-trib.rb check 192.168.31.187:7001

4.新增机器 （在其中一台机子上新增）master水平扩容

mkdir -p /var/redis/7007

port 7007

cluster-enabled yes

cluster-config-file /etc/redis-cluster/node-7007.conf

cluster-node-timeout 15000

daemonize yes

pidfile /var/run/redis_7007.pid

dir /var/redis/7007

logfile /var/log/redis/7007.log

bind 192.168.31.227

appendonly yes

redis-trib.rb add-node 192.168.31.227:7007 192.168.31.187:7001

redis-trib.rb check 192.168.31.187:7001

reshard一些数据过去

resharding的意思就是把一部分hash slot从一些node上迁移到另外一些node上

redis-trib.rb reshard 192.168.31.187:7001

要把之前3个master上，总共4096个hashslot迁移到新的第四个master上去

How many slots do you want to move (from 1 to 16384)?

1000

5、添加node作为slave

eshop-cache03

mkdir -p /var/redis/7008

port 7008

cluster-enabled yes

cluster-config-file /etc/redis-cluster/node-7008.conf

cluster-node-timeout 15000

daemonize yes

pidfile /var/run/redis_7008.pid

dir /var/redis/7008

logfile /var/log/redis/7008.log

bind 192.168.31.227

appendonly yes

redis-trib.rb add-node --slave --master-id 28927912ea0d59f6b790a50cf606602a5ee48108 192.168.31.227:7008 192.168.31.187:7001

6.删除node

先用resharding将数据都移除到其他节点，确保node为空之后，才能执行remove操作

redis-trib.rb del-node 192.168.31.187:7001 bd5a40a6ddccbd46a0f4a2208eb25d2453c2a8db