Redis集群的搭建

Redis集群的搭建

分析：

由于当集群中的某一台redis主机挂了，需要其他主机投票，当某台主机的得票数达到半数以上，其成为主机的要求，所有至少需要三台机器；又由于redis服务器要保证高可用，需要满足拥有16384个槽，若一台机器挂了，槽不完整，整个集群都不可用，所有每个主机需要一个备份机，及一共需要6台主机。

搭建伪分布式集群，可以在一台主机上运行多个redis实例。需要修改redis得端口号：7001-7006；

步骤：

1、复制多份redis实例到文件夹redis-cluster下

2、修改配置文件redis.conf

修改端口：

# Accept connections on the specified port, default is 6379 (IANA #815344).
# If port 0 is specified Redis will not listen on a TCP socket.
port 7001


改为后台启动
################################# GENERAL #####################################

# By default Redis does not run as a daemon. Use 'yes' if you need it.
# Note that Redis will write a pid file in /var/run/redis.pid when daemonized.
daemonize yes


打开集群模式：
################################ REDIS CLUSTER  ###############################
#
# ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
# WARNING EXPERIMENTAL: Redis Cluster is considered to be stable code, however
# in order to mark it as "mature" we need to wait for a non trivial percentage
# of users to deploy it in production.
# ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
#
# Normal Redis instances can't be part of a Redis Cluster; only nodes that are
# started as cluster nodes can. In order to start a Redis instance as a
# cluster node enable the cluster support uncommenting the following:
#
  cluster-enabled yes

3、复制多分redis实例：

4、修改redis.conf文件（如步骤2中），端口分别位7002、7003、7004、7005、7006；

5、启动所有实例；

cd redis01
./redis-server redis.conf
cd ..

cd redis02
./redis-server redis.conf
cd ..

cd redis03
./redis-server redis.conf
cd ..
cd redis04
./redis-server redis.conf
cd ..
cd redis05
./redis-server redis.conf
cd ..
cd redis06
./redis-server redis.conf
cd ..
~                                                                                                                                                                                                                
~

查看进程：

[root@localhost redis-cluster]# ps -ef|grep redis
root      3261     1  0 06:19 ?        00:00:00 ./redis-server 127.0.0.1:7001 [cluster]
root      3265     1  0 06:19 ?        00:00:00 ./redis-server 127.0.0.1:7002 [cluster]
root      3269     1  0 06:19 ?        00:00:00 ./redis-server 127.0.0.1:7003 [cluster]
root      3273     1  0 06:19 ?        00:00:00 ./redis-server 127.0.0.1:7004 [cluster]
root      3277     1  0 06:19 ?        00:00:00 ./redis-server 127.0.0.1:7005 [cluster]
root      3279     1  0 06:19 ?        00:00:00 ./redis-server 127.0.0.1:7006 [cluster]
root      3285  3026  0 06:19 pts/1    00:00:00 grep --color=auto redis
[root@localhost redis-cluster]# ll

6、使用ruby脚本搭建集群。需要ruby的运行环境。

安装ruby

yum install ruby

yum install rubygems

(gem install redis-3.0.0.gem)

7、运行：

./redis-trib.rb create --replicas 1 127.0.0.1:7001 127.0.0.1:7002 127.0.0.1:7003 127.0.0.1:7004 127.0.0.1:7005 127.0.0.1:7006

yes

至此，集群搭建完成；那么如何连接集群？

随便进入一个redis实例内：

执行命令：-c参数不能缺少

./redis-cli -p 7006 -c

一些集群的命令：

cluster info
cluster nodes