NoSQL之Redis群集部署
文章目录
Redis 集群简介
Redis Cluster 即 Redis 集群，是 Redis 官方在 3.0
版本推出的一套分布式存储方案。完全去中心化，由多个节点组成，所有节点彼此互联。Redis
客户端可以直接连接任何一节点获取集群中的键值对，不需要中间代理，如果该节点不存在用户所指定的键值，其内部会自动把客户端重定向到键值所在的节点。Redis 集群是一个网状结构，每个节点都通过 TCP 连接跟其他每个节点连接。在一个有 N 个节点的集群中，每个节点都有 N-1 个流出的
TCP 连接，和 N-1 个流入的连接，这些 TCP 连接会永久保持。
数据分区
Redis 集群会将用户数据分散保存至各个节点中，突破单机 Redis 内存最大存储容量。集群引入了 哈希槽slot的概念，其搭建完成后会生
16384 个哈希槽slot，同时会根据节点的数量大致均等的将 16384
个哈希槽映射到不同的节点上。当用户存储key-value时，集群会先对key进行 CRC16 校验然后对 16384
取模来决定key-value放置哪个槽，从而实现自动分割数据到不同的节点上。
数据冗余
Redis
集群支持主从复制和故障恢复。集群使用了主从复制模型，每个主节点master应至少有一个从节点slave。假设某个主节点故障，其所有子节点会广播一个数据包给集群里的其他主节点来请求选票，一旦某个从节点收到了大多数主节点的回应，那么它就赢得了选举，被推选为主节点，负责处理之前旧的主节点负责的哈希槽。
一：部署Redis群集
1.1：主从服务器部署Redis
依据 Redis Cluster 内部故障转移实现原理，Redis 集群至少需要 3 个主节点，而每个主节点至少有 1 从节点，因此搭建一个集群至少包含 6 个节点，三主三从，并且分别部署在不同机器上。
由于条件有限我们只能在两台创建一个伪群集
//主从服务器的部署都是一样的，在此仅展示主服务器的部署
[root@master1 ~]# yum install gcc gcc-c++ make -y //安装环境组件编译器
[root@master1 redis]# tar zxvf redis-5.0.7.tar.gz -C /opt //redis源码包可以直接到官网下载
[root@master1 redis]# cd /opt/redis-5.0.7/
[root@master1 redis-5.0.7]# make '//直接进行make'
[root@master1 redis-5.0.7]# make PREFIX=/usr/local/redis/ install //指定redis目录并安装
[root@master1 redis-5.0.7]# cd utils/'//回到redis源码包解压目录'
[root@master1 utils]# ./install_server.sh '//执行脚本进行配置'
Welcome to the redis service installer
This script will help you easily set up a running redis server
Please select the redis port for this instance: [6379] '//选择redis默认接口，直接回车'
Selecting default: 6379
Please select the redis config file name [/etc/redis/6379.conf] '//选择redis默认配置文件名称，直接回车'
Selected default - /etc/redis/6379.conf
Please select the redis log file name [/var/log/redis_6379.log] '//选择默认redis日志文件名称，直接回车'
Selected default - /var/log/redis_6379.log
Please select the data directory for this instance [/var/lib/redis/6379] '//选择默认接口的默认数据文件，直接回车'
Selected default - /var/lib/redis/6379
Please select the redis executable path [] /usr/local/redis/bin/redis-server '//选择redis可执行文件路径，需要手动输入此路径：/usr/local/redis/bin/redis-server'
Selected config: '//选择的配置清单展示'
Port : 6379
Config file : /etc/redis/6379.conf
Log file : /var/log/redis_6379.log
Data dir : /var/lib/redis/6379
Executable : /usr/local/redis/bin/redis-server
Cli Executable : /usr/local/redis/bin/redis-cli
Is this ok? Then press ENTER to go on or Ctrl-C to abort. '//直接回车完成配置'
Copied /tmp/6379.conf => /etc/init.d/redis_6379
Installing service...
Successfully added to chkconfig!
Successfully added to runlevels 345!
Starting Redis server...
Installation successful!
[root@master1 utils]# ln -s /usr/local/redis/bin/* /usr/local/bin '//将redis命令创建软连接，便于系统识别'
[root@master1 utils]# netstat -ntap |grep 6379
tcp 0 0 127.0.0.1:6379 0.0.0.0:* LISTEN
1.2：主从服务器文件修改
[root@master1 utils]# vim /etc/redis/6379.conf //修改主配置文件
#bind 127.0.0.1 '//注释第70行的监听127地址 表示监听所有地址
protected-mode no '//去掉第89行注释关闭安全保护'
port 6379 '//去掉第93行注释,开启端口6379'
daemonize yes '//去掉第137行注释,以独立进程启动'
cluster-enabled yes '//去掉第833行注释,开启群集功能 注意顶行写'
cluster-config-file nodes-6379.conf '//去掉第841行注释,群集名称文件设置'
cluster-node-timeout 15000 '//去掉第847行注释,群集超时时间设置'
appendonly yes '//去掉第700行注释,开启aof持久化'
[root@master1 utils]# cd /var/lib/redis/6379/
[root@master1 6379]# /etc/init.d/redis_6379 restart '//重启redis服务'
[root@master1 6379]# ls
appendonly.aof dump.rdb nodes-6379.conf '//生成了三个文件，appendonly.aof是AOF持久化文件，dump.rdb是RDB快照文件，nodes-6379.conf是节点首次启动生成的配置文件'
1.3：主服务器安装rvm，RUBY控制集软件
[root@master01 opt]# gpg --keyserver hkp://keys.gnupg.net --recv-keys 409B6B1796C275462A1703113804BB82D39DC0E3
gpg: 已创建目录‘/root/.gnupg’
gpg: 新的配置文件‘/root/.gnupg/gpg.conf’已建立
gpg: 警告：在‘/root/.gnupg/gpg.conf’里的选项于此次运行期间未被使用
gpg: 钥匙环‘/root/.gnupg/secring.gpg’已建立
gpg: 钥匙环‘/root/.gnupg/pubring.gpg’已建立
gpg: 下载密钥‘D39DC0E3’，从 hkp 服务器 keys.gnupg.net
'//把脚本文件拷贝到opt'
[root@master01 opt]# rz -E
rz waiting to receive.
[root@master01 opt]# ls
redis-5.0.7 redis-5.0.7.tar.gz rh rvm-installer.sh shuai.sh
'//增加执行权限'
[root@master01 opt]# chmod +x rvm-installer.sh
'//执行脚本'
[root@master01 opt]# ./rvm-installer.sh
'//执行环境变量'
[root@master01 opt]# source /etc/profile.d/rvm.sh
'//列出Ruby可安装的版本'
[root@master01 opt]# rvm list known
'//安装Ruby2.4.10'
[root@master01 opt]# rvm install 2.4.10
'//使用Ruby2.4.10版本'
rvm user 2.4.10
'//再次安装Redis'
gem install redis
1.4：主从服务器自行添加两张网卡（模拟6个节点）
//查看新增网卡
[root@master01 opt]# ifconfig
ens36: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 20.0.0.8 netmask 255.255.255.0 broadcast 20.0.0.255
inet6 fe80::45d1:cf4f:e061:4ff1 prefixlen 64 scopeid 0x20<link>
ether 00:0c:29:84:c1:ed txqueuelen 1000 (Ethernet)
RX packets 317 bytes 39238 (38.3 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 171 bytes 22632 (22.1 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
ens37: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 20.0.0.9 netmask 255.255.255.0 broadcast 20.0.0.255
inet6 fe80::10b1:3e47:969:95 prefixlen 64 scopeid 0x20<link>
ether 00:0c:29:84:c1:f7 txqueuelen 1000 (Ethernet)
RX packets 122 bytes 22029 (21.5 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 35 bytes 6456 (6.3 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
//关闭防火墙重启服务
[root@master01 opt]# systemctl restart network
[root@master01 opt]# systemctl stop firewalld.service
[root@master01 opt]# setenforce 0
[root@localhost opt]# ifconfig
'//查看网卡信息'
ens36: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 20.0.0.10 netmask 255.255.255.0 broadcast 20.0.0.255
inet6 fe80::b6a4:8fa8:6f93:b5fa prefixlen 64 scopeid 0x20<link>
ether 00:0c:29:bd:4f:6d txqueuelen 1000 (Ethernet)
RX packets 94 bytes 15273 (14.9 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 35 bytes 6496 (6.3 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
ens37: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 20.0.0.11 netmask 255.255.255.0 broadcast 20.0.0.255
inet6 fe80::7d35:a3bf:dc95:8809 prefixlen 64 scopeid 0x20<link>
ether 00:0c:29:bd:4f:63 txqueuelen 1000 (Ethernet)
RX packets 85 bytes 13072 (12.7 KiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 35 bytes 6496 (6.3 KiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
'//重启网卡'
[root@localhost ~]# service network restart
Restarting network (via systemctl): [ 确定 ]
[root@localhost ~]# systemctl stop firewalld.service
[root@localhost ~]# setenforce 0
1.5：主服务器上创建群集
'//配置监听所有的端口'
[root@master01 opt]# vim /etc/redis/6379.conf
bind 20.0.0.41 20.0.0.8 20.0.0.9
'//重启服务'
[root@master01 opt]# /etc/init.d/redis_6379 restart
'//'
[root@master01 opt]# redis-cli --cluster create 20.0.0.41:6379 20.0.0.8:6379 20.0.0.9:6379 20.0.0.42:6379 20.0.0.10:6379 20.0.0.11:6379 --cluster-replicas 1
>>> Performing hash slots allocation on 6 nodes...
Master[0] -> Slots 0 - 5460
Master[1] -> Slots 5461 - 10922
Master[2] -> Slots 10923 - 16383
Adding replica 20.0.0.10:6379 to 20.0.0.41:6379
Adding replica 20.0.0.11:6379 to 20.0.0.8:6379
Adding replica 20.0.0.42:6379 to 20.0.0.9:6379
M: 0bf9a12ac900d640c37b4dca4beecdb9bf71392d 20.0.0.41:6379
slots:[0-5460] (5461 slots) master
M: 0bf9a12ac900d640c37b4dca4beecdb9bf71392d 20.0.0.8:6379
slots:[5461-10922] (5462 slots) master
M: 0bf9a12ac900d640c37b4dca4beecdb9bf71392d 20.0.0.9:6379
slots:[10923-16383] (5461 slots) master
S: fa928bf59976325d9cd19a5bb64b629acf8c5c89 20.0.0.42:6379
replicates 0bf9a12ac900d640c37b4dca4beecdb9bf71392d
S: fa928bf59976325d9cd19a5bb64b629acf8c5c89 20.0.0.10:6379
replicates 0bf9a12ac900d640c37b4dca4beecdb9bf71392d
S: fa928bf59976325d9cd19a5bb64b629acf8c5c89 20.0.0.11:6379
replicates 0bf9a12ac900d640c37b4dca4beecdb9bf71392d
Can I set the above configuration? (type 'yes' to accept): yes '//输入yes'
>>> Nodes configuration updated
>>> Assign a different config epoch to each node
>>> Sending CLUSTER MEET messages to join the cluster
Waiting for the cluster to join
>>> Performing Cluster Check (using node 20.0.0.41:6379)
M: 0bf9a12ac900d640c37b4dca4beecdb9bf71392d 20.0.0.41:6379
slots:[0-16383] (16384 slots) master
1 additional replica(s)
S: fa928bf59976325d9cd19a5bb64b629acf8c5c89 20.0.0.42:6379
slots: (0 slots) slave
replicates 0bf9a12ac900d640c37b4dca4beecdb9bf71392d
[OK] All nodes agree about slots configuration.
>>> Check for open slots...
>>> Check slots coverage...
[OK] All 16384 slots covered.
//登录
[root@master01 opt]# redis-cli -c -h 20.0.0.41
20.0.0.41:6379> quit
[root@master01 opt]# redis-cli -c -h 20.0.0.8
20.0.0.8:6379> quit
[root@master01 opt]# redis-cli -c -h 20.0.0.9
//群集验证
[root@master01 opt]# redis-cli -c -h 20.0.0.41 '//登录到14的数据库'
20.0.0.41:6379> set name lisi '//创建一个键值'
OK
20.0.0.41:6379> get name '//查看name键的值'
"lisi"
20.0.0.41:6379> exit '//退出'
[root@master01 opt]# redis-cli -c -h 20.0.0.8
20.0.0.8:6379> keys *
1) "name"
20.0.0.8:6379> get name '//查看name键的值'
"lisi"
[root@master01 opt]# redis-cli -c -h 20.0.0.9 '//登录到9的数据库'
20.0.0.9:6379> keys * '//查看键'
1) "name"
20.0.0.9:6379> get name '//查看键的值'
"lisi"
[root@master01 opt]# redis-cli -c -h 20.0.0.42 '//登录从服务器的42数据库'
20.0.0.42:6379> keys *
1) "name"
20.0.0.42:6379> get name
-> Redirected to slot [5798] located at 20.0.0.41:6379 '//可以看出从主服务器41数据库读写的'
"lisi"
[root@master01 opt]# redis-cli -c -h 20.0.0.10 '//可以看出主从的数据都是同步的'
20.0.0.10:6379> keys *
1) "name"
20.0.0.10:6379> get name
-> Redirected to slot [5798] located at 20.0.0.41:6379
"lisi"
20.0.0.41:6379> exit
[root@master01 opt]# redis-cli -c -h 20.0.0.11
20.0.0.11:6379> keys *
1) "name"
20.0.0.11:6379> get name
-> Redirected to slot [5798] located at 20.0.0.41:6379
"lisi"
20.0.0.41:6379> '//你会发现自动切换到41数据库'
//设置主服务器41数据库失效时间为50s
20.0.0.41:6379> expire name 50
(integer) 1
20.0.0.41:6379> ttl name '//查看失效时间'
(integer) 44
20.0.0.41:6379> ttl name
(integer) 41
20.0.0.41:6379> keys * '//查看键值已经没了'
(empty list or set)
//登录从服务器42数据库
[root@master01 opt]# redis-cli -c -h 20.0.0.42
20.0.0.42:6379> keys * '//可以看到数据已经没了'
(empty list or set)