codis实现redis分片和在线扩展

Codis是一个开源的分布式redis解决方案，由以下四个组件组成：codis-proxy:后端redis的代理，本事实现了redis协议。codis-config:是codis的管理配置工具，用于..

Codis是一个开源的分布式redis解决方案，由以下四个组件组成：

codis-proxy:后端redis的代理，本事实现了redis协议。

codis-config:是codis的管理配置工具，用于增删redis server、操作数据迁移。

zookeeper:用来存放数据路由表和codis-proxy节点的元信息,codis-config发起的命令都会通过 zookeeper同步到各个存活的codis-proxy。

codis-server:codis项目维护的一个 redis 分支, 基于 2.8.13 开发, 加入了 slot 的支持和原子的数据迁移指令，如果要使用codis的在线扩展迁移功能的话必须使用codis自带的codis-server，codis不支持对原生redis做在线的扩展和数据迁移。

节点规划：

codis-proxy
192.168.0.100:19000

codis-config
192.168.0.100

codis-server1
192.168.0.100:6381

codis-server2192.168.0.100:6382

codis-server3192.168.0.100:6380

codis-server4192.168.0.100:6383

1、安装配置

a、首先安装golang

## 解压下载好的go软件包 $ tar xf/opt/go1.4.2.linux-amd64.tar.gz -C/usr/local/ ## 配置环境变量 在.bash_profile中加入go的相关环境变量，并使新的环境变量生效 PATH=$PATH:$HOME/bin exportGOROOT=/usr/local/go exportGOOS=linux exportGOARCH=amd64 exportGOBIN=$GOROOT/bin exportGOPATH=/opt/mygo PATH=$PATH:$GOBIN export PATH ##编写一个 测试程序验证go是否安装成功 $ cat hello.go package main import"fmt" func main() { fmt.Printf("hello, world\n") } ## 运行测试程序，输出hello,word说明go已经安装成功 $ go run hello.go hello, world

b、安装codis

## 安装工具软件 $ yum install gccmake git -y ## 下载codis,会下载到环境变量GOPATH指定的目录 $ go get github.com/wandoulabs/codis#ssdb-server config packagegithub.com/wandoulabs/codis imports github.com/wandoulabs/codis imports github.com/wandoulabs/codis: nobuildable Go source files in /opt/mygo/src/github.com/wandoulabs/codis ## 下载完成后进入/opt/mygo/src/github.com/wandoulabs/codis $ cd /opt/mygo/src/github.com/wandoulabs/codis ## 执行安装命令 $ ./bootstrap.sh ## 这一步时间稍久，会下载一些文件目录到本地，耐心等待即可

c、安装zookeeper

##　解压zookeeper $ tar xfzookeeper-3.4.6.tar.gz -C /opt/ ##　进入zk的安装目录，修改配置文件 $ cd /opt/zookeeper-3.4.6 $ cp conf/zoo_sample.cfgconf/zoo.cfg $ vim conf/zoo.cfg tickTime=2000 initLimit=10 syncLimit=5 dataDir=/data/zookeeper dataLogDir=/opt/zookeeper-3.4.6/logs clientPort=2181 ## 创建所需要的目录 mkdir /data/zookeeper -p mkdir /opt/zookeeper-3.4.6/logs ## 启动zk $ /opt/zookeeper-3.4.6/bin/zkServer.sh start JMX enabled bydefault Using config:/opt/zookeeper-3.4.6/bin/../conf/zoo.cfg Starting zookeeper... STARTED ## 验证是否启动成功,若2181端口被监听，则表示成功 $ netstat-alnut|grep 2181 tcp 0 0 :::2181 :::* LISTEN

d、配置codis

## codis中配置zk的信息 $ cd /opt/mygo/src/github.com/wandoulabs/codis/sample/ ## 修改config.ini $ vim config.ini zk=localhost:2181 product=codis_proxy proxy_id=proxy_1 net_timeout=5 dashboard_addr=localhost:18087 coordinator=zookeeper

2、启动codis

a、

## 进入相关目录 $ cd /opt/mygo/src/github.com/wandoulabs/codis/sample/ ## 启动dashboard ./start_dashboard.sh ## 验证是否成功 $ netstat -alnut|grep 18087 tcp 0 0 :::18087 :::* LISTE

：

b、初始化slots

##进入相关目录 $ cd /opt/mygo/src/github.com/wandoulabs/codis/sample/ ## 执行初始化 $ ../bin/codis-config slot init { "msg": "OK", "ret": 0 }

c、启动codis-server

## codis自带有一个启动脚本，会启动两个codis-server，监听端口为6381和6382 [root@mgs02 sample]#./start_redis.sh sleep 3s [6294] 09 Apr 14:28:02.796* Increased maximum number of open files to 10032 (it was originally set to1024). _._ _.-``__ ''-._ _.-`` `. `_. ''-._ Redis 2.8.13 (1e823fd3/1) 64 bit .-`` .-```. ```\/ _.,_ ''-._ ( ' , .-` | `, ) Running in stand alone mode |`-._`-...-` __...-.``-._|'` _.-'| Port: 6381 | `-._ `._ / _.-' | PID: 6294 `-._ `-._ `-./ _.-' _.-' |`-._`-._ `-.__.-' _.-'_.-'| | `-._`-._ _.-'_.-' | `-._ `-._`-.__.-'_.-' _.-' |`-._`-._ `-.__.-' _.-'_.-'| | `-._`-._ _.-'_.-' | `-._ `-._`-.__.-'_.-' _.-' `-._ `-.__.-' _.-' `-._ _.-' `-.__.-' [6294] 09 Apr14:28:02.814 # Server started, Redis version 2.8.13 [6294] 09 Apr14:28:02.814 # WARNING overcommit_memory is set to 0! Background save may failunder low memory condition. To fix this issue add 'vm.overcommit_memory = 1' to/etc/sysctl.conf and then reboot or run the command 'sysctlvm.overcommit_memory=1' for this to take effect. [6294] 09 Apr14:28:02.814 * The server is now ready to accept connections on port 6381 [6295] 09 Apr14:28:02.795 * Increased maximum number of open files to 10032 (it wasoriginally set to 1024). _._ _.-``__ ''-._ _.-`` `. `_. ''-._ Redis 2.8.13 (1e823fd3/1) 64 bit .-`` .-```. ```\/ _.,_ ''-._ ( ' , .-` | `, ) Running in stand alone mode |`-._`-...-` __...-.``-._|'` _.-'| Port: 6382 | `-._ `._ / _.-' | PID: 6295 `-._ `-._ `-./ _.-' _.-' |`-._`-._ `-.__.-' _.-'_.-'| | `-._`-._ _.-'_.-' | `-._ `-._`-.__.-'_.-' _.-' |`-._`-._ `-.__.-' _.-'_.-'| | `-._`-._ _.-'_.-' | `-._ `-._`-.__.-'_.-' _.-' `-._ `-.__.-' _.-' `-._ _.-' `-.__.-' [6295] 09 Apr14:28:02.811 # Server started, Redis version 2.8.13 [6295] 09 Apr14:28:02.811 # WARNING overcommit_memory is set to 0! Background save may failunder low memory condition. To fix this issue add 'vm.overcommit_memory = 1' to/etc/sysctl.conf and then reboot or run the command 'sysctlvm.overcommit_memory=1' for this to take effect. [6295] 09 Apr 14:28:02.812 * The server is nowready to accept connections on port 6382