一,规划 redis cluster
1,cluster采用六台redis,3主3从
redis1 : ip: 172.17.0.2
redis2 : ip: 172.17.0.3
redis3 : ip: 172.17.0.4
redis4 : ip: 172.17.0.5
redis5 : ip: 172.17.0.6
redis6 : ip: 172.17.0.7
2,为什么需要6个节点?
redis主从集群最少需要6个节点
master节点至少要3个,slave节点也是3个,
因为一个redis集群要对外提供可用的服务,那么集群中必须要有过半的master节点正常工作。
所以如果想搭建一个能够允许 n 个master节点挂掉的集群,那么就要搭建2n+1个master节点的集群。
2个节点,一个宕掉,剩下的1个不超过1半(1),集群停止工作
3个节点,一个宕掉,剩下的两个超过1半(1.5),集群继续工作
4个节点,一个宕掉,剩下的3个超过1半(2个),集群继续工作
4个节点,两个宕掉,剩下的2个不超过1半(2个),集群停止工作
3个节点和4个节点,都是只允许一个节点宕掉,
可见3个是最实际的选择
说明:刘宏缔的架构森林是一个专注架构的博客,地址:https://www.cnblogs.com/architectforest
对应的源码可以访问这里获取: https://github.com/liuhongdi/
说明:作者:刘宏缔 邮箱: [email protected]
二,在每台机器上安装redis,操作相同
1,安装wget
[root@redis source]# yum install wget
2,安装gcc
[root@redis source]# yum install gcc
3,安装tcl
[root@redis source]# yum install tcl
4,安装make
[root@redis redis-5.0.7]# yum install make
5,下载redis
[root@redis source]# wget http://download.redis.io/releases/redis-5.0.7.tar.gz
6,解压redis
[root@redis source]# tar -zxvf redis-5.0.7.tar.gz
7,编译:
[root@redis source]# cd redis-5.0.7
[root@redis redis-5.0.7]# make MALLOC=libc
8,测试编译效果:
[root@redis redis-5.0.7]# make test
遇到报错:
You need tcl 8.5 or newer in order to run the Redis test
解决:我们已安装了tcl
make test找不到它是因为缺少which命令,
[root@redis redis-5.0.7]# yum install which
9,再来一次:
[root@redis redis-5.0.7]# make clean
[root@redis redis-5.0.7]# make MALLOC=libc
[root@redis redis-5.0.7]# make test
最终看到以下提示则表示编译无问题
\o/ All tests passed without errors!
10,安装
生成目录
[root@redis soft]# mkdir /usr/local/soft/redis5
[root@redis soft]# mkdir /usr/local/soft/redis5/bin
[root@redis soft]# mkdir /usr/local/soft/redis5/conf
复制文件
[root@redis soft]# cp /usr/local/source/redis-5.0.7/src/redis-cli /usr/local/soft/redis5/bin/
[root@redis soft]# cp /usr/local/source/redis-5.0.7/src/redis-server /usr/local/soft/redis5/bin/
[root@redis soft]# cp /usr/local/source/redis-5.0.7/redis.conf /usr/local/soft/redis5/conf/
三,在每台机器上配置redis,注意有区别的地方:
1,生成目录:
[root@redis soft]# mkdir /data/
[root@redis soft]# mkdir /data/redis
[root@redis soft]# mkdir /data/redis/data
[root@redis soft]# mkdir /data/redis/log
[root@redis soft]# mkdir /data/redis/cluster
说明:data存放rdb或aof
log存放日志
cluster存放cluster的配置文件nodes.conf
2,配置redis.conf
配置以下各项
#数据文件存储目录
dir /data/redis/data/ #日志级别
loglevel notice(使用这个默认值,不用变) #日志文件
logfile "/data/redis/log/redis.log" #是否以服务方式运行
daemonize yes #pid文件
pidfile /var/run/redis_6379.pid(使用这个默认值,不用变) #是否以cluster方式运行
cluster-enabled yes(此行取消注释即可) #cluster的配置缓存文件
cluster-config-file /data/redis/cluster/nodes-6379.conf #连接node的超时时间
cluster-node-timeout 15000(此行取消注释即可) #访问每台redis的密码
requirepass lhd123 #slave访问master的密码,注意与上一个相同
masterauth lhd123 #是否启用保护模式
protected-mode no #绑定ip:注意要改成自己当前机器的可访问的ip
#如果是127.0.0.1,则只能从本机访问
bind 172.17.0.2
说明:这里要注意的一点:
绑定ip:注意要改成自己当前机器的可访问的ip
四,给每台机器上的redis生成systemd启动文件,操作相同
1,生成service文件
[root@redis conf]# vi /lib/systemd/system/redis.service
内容:
[Unit]
Description=Redis
After=network.target [Service]
Type=forking
PIDFile=/var/run/redis_6379.pid
ExecStart=/usr/local/soft/redis5/bin/redis-server /usr/local/soft/redis5/conf/redis.conf
ExecReload=/bin/kill -s HUP $MAINPID
ExecStop=/bin/kill -s QUIT $MAINPID
PrivateTmp=true [Install]
WantedBy=multi-user.target
重载systemd服务
[root@redis conf]# systemctl daemon-reload
启动redis服务
[root@redis conf]# systemctl start redis
测试:
[root@redis conf]# /usr/local/soft/redis5/bin/redis-cli
127.0.0.1:6379> auth lhd123
OK
127.0.0.1:6379> keys *
(empty list or set)
127.0.0.1:6379> set a aaa
(error) CLUSTERDOWN Hash slot not served
系统提示hash slot还没分配,因为cluster还未创建
五,创建cluster,测试写入,(在任一台机器上操作)
1,创建cluster,在上面创建的任一台机器上操作即可
命令:
[root@redis1 /]# /usr/local/soft/redis5/bin/redis-cli -a lhd123 --cluster create 172.17.0.2:6379 172.17.0.3:6379
172.17.0.4:6379 172.17.0.5:6379 172.17.0.6:6379 172.17.0.7:6379 --cluster-replicas 1
在需要回答下面问题时:输入yes
Can I set the above configuration? (type 'yes' to accept): yes
看一个例子:
#-a: auth 访问密码
#--cluster create :用来创建集群
#--cluster-replicas :为集群中的每个主节点创建一个从节点
[root@redis1 conf]# /usr/local/soft/redis5/bin/redis-cli -a lhd123 --cluster create 172.17.0.2:6379 172.17.0.3:6379
172.17.0.4:6379 172.17.0.5:6379 172.17.0.6:6379 172.17.0.7:6379 --cluster-replicas 1 Warning: Using a password with '-a' or '-u' option on the command line interface may not be safe.
>>> Performing hash slots allocation on 6 nodes...
Master[0] -> Slots 0 - 5460
Master[1] -> Slots 5461 - 10922
Master[2] -> Slots 10923 - 16383
Adding replica 172.17.0.6:6379 to 172.17.0.2:6379
Adding replica 172.17.0.7:6379 to 172.17.0.3:6379
Adding replica 172.17.0.5:6379 to 172.17.0.4:6379
M: eb701616b26b5a350605ae3ea5f80e4fc79d84c3 172.17.0.2:6379
slots:[0-5460] (5461 slots) master
M: 5bdaafe57b1c46f61c5910d3822633a516feb4ae 172.17.0.3:6379
slots:[5461-10922] (5462 slots) master
M: e024e898a21f3f4051abfb0957046dc4a81ef947 172.17.0.4:6379
slots:[10923-16383] (5461 slots) master
S: 1ca00d6a680fc1b0d617a46996eaaefc3636fd5a 172.17.0.5:6379
replicates e024e898a21f3f4051abfb0957046dc4a81ef947
S: 9cd94c491211542dbfae96002489c9b63a5a54e7 172.17.0.6:6379
replicates eb701616b26b5a350605ae3ea5f80e4fc79d84c3
S: 6f90338cef5af2aa9f0580cd660c80d2ea5fab82 172.17.0.7:6379
replicates 5bdaafe57b1c46f61c5910d3822633a516feb4ae
Can I set the above configuration? (type 'yes' to accept): 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 172.17.0.2:6379)
M: eb701616b26b5a350605ae3ea5f80e4fc79d84c3 172.17.0.2:6379
slots:[0-5460] (5461 slots) master
1 additional replica(s)
S: 1ca00d6a680fc1b0d617a46996eaaefc3636fd5a 172.17.0.5:6379
slots: (0 slots) slave
replicates e024e898a21f3f4051abfb0957046dc4a81ef947
M: 5bdaafe57b1c46f61c5910d3822633a516feb4ae 172.17.0.3:6379
slots:[5461-10922] (5462 slots) master
1 additional replica(s)
M: e024e898a21f3f4051abfb0957046dc4a81ef947 172.17.0.4:6379
slots:[10923-16383] (5461 slots) master
1 additional replica(s)
S: 9cd94c491211542dbfae96002489c9b63a5a54e7 172.17.0.6:6379
slots: (0 slots) slave
replicates eb701616b26b5a350605ae3ea5f80e4fc79d84c3
S: 6f90338cef5af2aa9f0580cd660c80d2ea5fab82 172.17.0.7:6379
slots: (0 slots) slave
replicates 5bdaafe57b1c46f61c5910d3822633a516feb4ae
[OK] All nodes agree about slots configuration.
>>> Check for open slots...
>>> Check slots coverage...
[OK] All 16384 slots covered.
2,测试写入:
# -c: Enable cluster mode,用集群模式访问
# -h: Server hostname (default: 127.0.0.1),指定要访问的主机
[root@redis1 conf]# /usr/local/soft/redis5/bin/redis-cli -a lhd123 -c -h 172.17.0.2
Warning: Using a password with '-a' or '-u' option on the command line interface may not be safe.
172.17.0.2:6379> set c bb
-> Redirected to slot [7365] located at 172.17.0.3:6379
OK
172.17.0.3:6379> set d bb
-> Redirected to slot [11298] located at 172.17.0.4:6379
OK
172.17.0.4:6379> get b
-> Redirected to slot [3300] located at 172.17.0.2:6379
"bb"
172.17.0.2:6379> get c
-> Redirected to slot [7365] located at 172.17.0.3:6379
"bb"
172.17.0.3:6379> get d
-> Redirected to slot [11298] located at 172.17.0.4:6379
"bb"
六,查看cluster信息(在任一台机器上操作)
1,查看节点列表:
以集群方式登录redis-cli后查看
172.17.0.3:6379> CLUSTER NODES
9cd94c491211542dbfae96002489c9b63a5a54e7 172.17.0.6:6379@16379 slave eb701616b26b5a350605ae3ea5f80e4fc79d84c3 0 1586861138000 1 connected
5bdaafe57b1c46f61c5910d3822633a516feb4ae 172.17.0.3:6379@16379 myself,master - 0 1586861135000 2 connected 5461-10922
6f90338cef5af2aa9f0580cd660c80d2ea5fab82 172.17.0.7:6379@16379 slave 5bdaafe57b1c46f61c5910d3822633a516feb4ae 0 1586861137000 6 connected
e024e898a21f3f4051abfb0957046dc4a81ef947 172.17.0.4:6379@16379 master - 0 1586861136668 3 connected 10923-16383
1ca00d6a680fc1b0d617a46996eaaefc3636fd5a 172.17.0.5:6379@16379 slave e024e898a21f3f4051abfb0957046dc4a81ef947 0 1586861138674 3 connected
eb701616b26b5a350605ae3ea5f80e4fc79d84c3 172.17.0.2:6379@16379 master - 0 1586861136000 1 connected 0-5460
用 check命令查看
#--cluster check: 列出群集中的机器信息
[root@redis2 /]# /usr/local/soft/redis5/bin/redis-cli --cluster check -a lhd123 172.17.0.3:6379
Warning: Using a password with '-a' or '-u' option on the command line interface may not be safe.
172.17.0.3:6379 (5bdaafe5...) -> 2 keys | 5462 slots | 1 slaves.
172.17.0.4:6379 (e024e898...) -> 3 keys | 5461 slots | 1 slaves.
172.17.0.2:6379 (eb701616...) -> 2 keys | 5461 slots | 1 slaves.
[OK] 7 keys in 3 masters.
0.00 keys per slot on average.
>>> Performing Cluster Check (using node 172.17.0.3:6379)
M: 5bdaafe57b1c46f61c5910d3822633a516feb4ae 172.17.0.3:6379
slots:[5461-10922] (5462 slots) master
1 additional replica(s)
S: 9cd94c491211542dbfae96002489c9b63a5a54e7 172.17.0.6:6379
slots: (0 slots) slave
replicates eb701616b26b5a350605ae3ea5f80e4fc79d84c3
S: 6f90338cef5af2aa9f0580cd660c80d2ea5fab82 172.17.0.7:6379
slots: (0 slots) slave
replicates 5bdaafe57b1c46f61c5910d3822633a516feb4ae
M: e024e898a21f3f4051abfb0957046dc4a81ef947 172.17.0.4:6379
slots:[10923-16383] (5461 slots) master
1 additional replica(s)
S: 1ca00d6a680fc1b0d617a46996eaaefc3636fd5a 172.17.0.5:6379
slots: (0 slots) slave
replicates e024e898a21f3f4051abfb0957046dc4a81ef947
M: eb701616b26b5a350605ae3ea5f80e4fc79d84c3 172.17.0.2:6379
slots:[0-5460] (5461 slots) master
1 additional replica(s)
[OK] All nodes agree about slots configuration.
>>> Check for open slots...
>>> Check slots coverage...
[OK] All 16384 slots covered.
2,查看节点的信息:
使用CLUSTER INFO命令
#CLUSTER INFO:cluster的统计信息
172.17.0.3:6379> CLUSTER INFO
cluster_state:ok
cluster_slots_assigned:16384
cluster_slots_ok:16384
cluster_slots_pfail:0
cluster_slots_fail:0
cluster_known_nodes:6
cluster_size:3
cluster_current_epoch:6
cluster_my_epoch:2
cluster_stats_messages_ping_sent:2071
cluster_stats_messages_pong_sent:1919
cluster_stats_messages_meet_sent:1
cluster_stats_messages_sent:3991
cluster_stats_messages_ping_received:1915
cluster_stats_messages_pong_received:2072
cluster_stats_messages_meet_received:4
cluster_stats_messages_received:3991
七,创建redis cluster时遇到的报错或问题:
1,创建cluster时,停在Waiting for the cluster to join不动了
1,16379这个集群管理端口被防火墙做了拦截
2, docker环境中,nodes-6379.conf 文件中redis节点id如果相同也会有这个问题
删除文件后重启
例:
[root@redis1 conf]# rm /data/redis/cluster/nodes-6379.conf
rm: remove regular file '/data/redis/cluster/nodes-6379.conf'? y
2,客户端写入时报错:
(error) MOVED
例子:
172.17.0.2:6379> set a aaa
(error) MOVED 15495 172.17.0.4:6379
解决:
因为启动redis-cli时没有设置集群模式所导致
[root@redis1 conf]# /usr/local/soft/redis5/bin/redis-cli -c -h 172.17.0.2
3,客户端写入时报错:
(error) NOAUTH Authentication required.
例子:
[root@redis1 conf]# /usr/local/soft/redis5/bin/redis-cli -c -h 172.17.0.2
172.17.0.2:6379> auth lhd123
OK
172.17.0.2:6379> set a aaaa
-> Redirected to slot [15495] located at 172.17.0.4:6379
(error) NOAUTH Authentication required.
172.17.0.4:6379> auth "lhd123"
OK
172.17.0.4:6379> set a aaaa
OK
解决:
[root@redis1 conf]# /usr/local/soft/redis5/bin/redis-cli -a lhd123 -c -h 172.17.0.2
八,查看redis版本
[root@redis1 /]# /usr/local/soft/redis5/bin/redis-server --version
Redis server v=5.0.7 sha=00000000:0 malloc=libc bits=64 build=c52ab39fadfc446c
九,查看centos版本
[root@redis1 /]# cat /etc/redhat-release
CentOS Linux release 8.1.1911 (Core)
十,针对redis cluster中node的管理,请移步这一篇:
https://www.cnblogs.com/architectforest/p/12714889.html