redis集群主从slave调整成master redis集群主从配置

转载

mob64ca14137e4f 2024-04-19 10:27:45

redis主从和MySQL主从目的差不多，但redis主从配置很简单，主要在从节点配置文件指定主节点ip和端口：slaveof 192.168.1.197 6379，然后启动主从，主从就搭建好了redis主从中如果主节点发生故障，不会自动切换，需要借助redis的Sentinel或者keepalive来实现主的故障转移

redis集群是一个无中心的分布式redis存储架构，可以在多个节点之间进行数据共享，解决了redis高可用、可扩展等问题，redis集群提供了以下两个好处
1、将数据自动切分(split)到多个节点
2、当集群中的某一个节点故障时，redis还可以继续处理客户端的请求。
一个 Redis 集群包含 16384 个哈希槽（hash slot），数据库中的每个数据都属于这16384个哈希槽中的一个。集群使用公式 CRC16(key) % 16384 来计算键 key 属于哪个槽。集群中的每一个节点负责处理一部分哈希槽。
集群中的主从复制
集群中的每个节点都有1个至N个复制品，其中一个为主节点，其余的为从节点，如果主节点下线了，集群就会把这个主节点的一个从节点设置为新的主节点，继续工作。这样集群就不会因为一个主节点的下线而无法正常工作

下面开始搭建redis集群

由于最小的redis集群需要3个主节点，一台机器可运行多个redis实例，我搭建时使用两台机器，6个redis实例，其中三个主节点，三个从节点作为备份
网上很多使用单台服务器开6个端口，操作差不多，只是配置基本相对简单点，多台服务器更接近生产环境

redis 6个节点的ip和端口对应关系

server1:
 192.168.1.198:7000
 192.168.1.198:7001
 192.168.1.198:7002
 server2：
 192.168.1.199:7003
 192.168.1.199:7004
 192.168.1.199:7005

1、安装需要的依赖包

[python] view plain copy

1. [root@localhost ~]# yum install gcc gcc-c++ kernel-devel automake autoconf libtool make wget tcl vim ruby rubygems unzip git -y

2、两台机器分别下载redis并安装

[python] view plain copy

1. [root@localhost src]# cd /usr/local/
2. [root@localhost local]# wget http://download.redis.io/releases/redis-3.0.6.tar.gz
3. [root@localhost local]# tar xzf redis-3.0.6.tar.gz
4. [root@localhost local]# cd redis-3.0.6
5. [root@localhost redis-3.0.6]# make

3、创建集群需要的目录

server1执行：

[python] view plain copy

1. mkdir -p /usr/local/cluster  
2. cd /usr/local/cluster  
3. mkdir 7000  
4. mkdir 7001  
5. mkdir 7002

server2执行：

[python] view plain copy

1. mkdir -p /usr/local/cluster  
2. cd /usr/local/cluster  
3. mkdir 7003  
4. mkdir 7004  
5. mkdir 7005  
 4、修改配置文件redis.conf
 cp /usr/local/redis-3.0.6/redis.conf  /usr/local/cluster
 cd /usr/local/cluster
 vi redis.conf

[python] view plain copy

##注意每个实例的端口号不同

1. port 7000  
2. daemonize yes  
3. cluster-enabled yes  
4. cluster-config-file nodes.conf  
5. cluster-node-timeout 5000  
6. appendonly yes

##修改完redis.conf配置文件中的这些配置项之后把这个配置文件分别拷贝到7000/7001/7002/7003/7004/7005节点目录下
server1执行：

[python] view plain copy

1. cp /usr/local/cluster/redis.conf /usr/local/cluster/7000  
2. cp /usr/local/cluster/redis.conf /usr/local/cluster/7001  
3. cp /usr/local/cluster/redis.conf /usr/local/cluster/7002

server2执行：

[python] view plain copy

1. cp /usr/local/cluster/redis.conf /usr/local/cluster/7003  
2. cp /usr/local/cluster/redis.conf /usr/local/cluster/7004  
3. cp /usr/local/cluster/redis.conf /usr/local/cluster/7005

##注意：拷贝完成之后要分别修改7001/7002/7003/7004/7005目录下面redis.conf文件中的port参数，分别改为对应的文件夹的名称

5、分别启动这6个redis实例，并查看是否成功：ps -ef|grep redis
server1执行：

[python] view plain copy

1. [root@localhost cluster]# cd /usr/local/cluster/7000
2. [root@localhost 7000]# redis-server redis.conf
3. [root@localhost 7000]# cd /usr/local/cluster/7001
4. [root@localhost 7001]# redis-server redis.conf
5. [root@localhost 7001]# cd /usr/local/cluster/7002
6. [root@localhost 7002]# redis-server redis.conf
7. [root@localhost 7002]# ps -ef|grep redis
8. root      2741     1  0 09:39 ?        00:00:00 redis-server *:7000 [cluster]  
9. root      2747     1  0 09:40 ?        00:00:00 redis-server *:7001 [cluster]  
10. root      2751     1  0 09:40 ?        00:00:00 redis-server *:7002 [cluster]  
11. root      2755  2687  0 09:40 pts/0    00:00:00 grep redis

server2执行：

[python] view plain copy

1. [root@localhost cluster]# cd /usr/local/cluster/7003
2. [root@localhost 7003]# redis-server redis.conf
3. [root@localhost 7003]# cd /usr/local/cluster/7004
4. [root@localhost 7004]# redis-server redis.conf
5. [root@localhost 7004]# cd /usr/local/cluster/7005
6. [root@localhost 7005]# redis-server redis.conf
7. [root@localhost 7005]# ps -ef|grep redis
8. root      1619     1  0 09:40 ?        00:00:00 redis-server *:7003 [cluster]  
9. root      1623     1  0 09:40 ?        00:00:00 redis-server *:7004 [cluster]  
10. root      1627     1  0 09:41 ?        00:00:00 redis-server *:7005 [cluster]  
11. root      1631  1563  0 09:41 pts/0    00:00:00 grep redis

6、执行redis的创建集群命令创建集群（注意ip地址和端口号）

[python] view plain copy

1. [root@localhost cluster]# cd /usr/local/redis-3.0.6/src
2. [root@localhost src]# ./redis-trib.rb  create --replicas 1 192.168.1.198:7000 192.168.1.198:7001 192.168.1.198:7002 192.168.1.199:7003 192.168.1.199:7004 192.168.1.199:7005

6.1到这一步因为前面第1步装了依赖包，未提示ruby和rubygems的错误，但还是会报错，提示不能加载redis，是因为缺少redis和ruby的接口，使用gem 安装
错误内容：

/usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `gem_original_require': no such file to load -- redis (LoadError)
         from /usr/lib/ruby/site_ruby/1.8/rubygems/custom_require.rb:31:in `require'
         from ./redis-trib.rb:25

解决：gem install redis
6.2 再次执行第6步的命令，正常执行，提示是否允许修改配置文件，输入yes，然后整个集群配置完成！

[python] view plain copy

1. [root@localhost src]# ./redis-trib.rb  create --replicas 1 192.168.1.198:7000 192.168.1.198:7001 192.168.1.198:7002 192.168.1.199:7003 192.168.1.199:7004 192.168.1.199:7005
2. >>> Creating cluster  
3. >>> Performing hash slots allocation on 6 nodes...  
4. Using 3 masters:  
5. 192.168.1.199:7003  
6. 192.168.1.198:7000  
7. 192.168.1.199:7004  
8. Adding replica 192.168.1.198:7001 to 192.168.1.199:7003  
9. Adding replica 192.168.1.199:7005 to 192.168.1.198:7000  
10. Adding replica 192.168.1.198:7002 to 192.168.1.199:7004  
11. M: 2f70e9f2b4a06a846e46d7034a54e0fe6971beea 192.168.1.198:7000  
12.    slots:5461-10922 (5462 slots) master  
13. S: e60f49920cf8620927b200b0001892d08067d065 192.168.1.198:7001  
14.    replicates 02f1958bd5032caca2fd47a56362c8d562d7e621  
15. S: 26101db06b5c2d4431ca8308cf43d51f6939b4fc 192.168.1.198:7002  
16.    replicates 6c4f18b9e8729c3ab5d43b00b0bc1e2ee976f299  
17. M: 02f1958bd5032caca2fd47a56362c8d562d7e621 192.168.1.199:7003  
18.    slots:0-5460 (5461 slots) master  
19. M: 6c4f18b9e8729c3ab5d43b00b0bc1e2ee976f299 192.168.1.199:7004  
20.    slots:10923-16383 (5461 slots) master  
21. S: ebb27bd0a48b67a4f4e0584be27c1c909944e935 192.168.1.199:7005  
22.    replicates 2f70e9f2b4a06a846e46d7034a54e0fe6971beea  
23. Can I set the above configuration? (type 'yes'
24. >>> Nodes configuration updated  
25. >>> Assign a different config epoch to each node  
26. >>> Sending CLUSTER MEET messages to join the cluster  
27. Waiting for the cluster to join...  
28. >>> Performing Cluster Check (using node 192.168.1.198:7000)  
29. M: 2f70e9f2b4a06a846e46d7034a54e0fe6971beea 192.168.1.198:7000  
30.    slots:5461-10922 (5462 slots) master  
31. M: e60f49920cf8620927b200b0001892d08067d065 192.168.1.198:7001  
32.    slots: (0 slots) master  
33.    replicates 02f1958bd5032caca2fd47a56362c8d562d7e621  
34. M: 26101db06b5c2d4431ca8308cf43d51f6939b4fc 192.168.1.198:7002  
35.    slots: (0 slots) master  
36.    replicates 6c4f18b9e8729c3ab5d43b00b0bc1e2ee976f299  
37. M: 02f1958bd5032caca2fd47a56362c8d562d7e621 192.168.1.199:7003  
38.    slots:0-5460 (5461 slots) master  
39. M: 6c4f18b9e8729c3ab5d43b00b0bc1e2ee976f299 192.168.1.199:7004  
40.    slots:10923-16383 (5461 slots) master  
41. M: ebb27bd0a48b67a4f4e0584be27c1c909944e935 192.168.1.199:7005  
42.    slots: (0 slots) master  
43.    replicates 2f70e9f2b4a06a846e46d7034a54e0fe6971beea  
44. [OK] All nodes agree about slots configuration.  
45. >>> Check for open slots...  
46. >>> Check slots coverage...  
47. [OK] All 16384 slots covered.

7、测试集群

server1上登录redis客户端并执行

[python] view plain copy

1. [root@localhost src]# redis-cli -c -p 7000
2. 127.0.0.1:7000> get key  
3. -> Redirected to slot [12539] located at 192.168.1.199:7004  
4. "val"
5. 192.168.1.199:7004> set name test  
6. -> Redirected to slot [5798] located at 192.168.1.198:7000  
7. OK  
8. 192.168.1.198:7000> set adress shanghai  
9. -> Redirected to slot [1562] located at 192.168.1.199:7003  
10. OK  
11. 192.168.1.199:7003>

server2上登录redis客户端并执行

[python] view plain copy

1. [root@localhost src]# redis-cli -c -p 7003
2. 127.0.0.1:7003> set key val  
3. -> Redirected to slot [12539] located at 192.168.1.199:7004  
4. OK  
5. 192.168.1.199:7004> get keyv  
6. "val"
7. 192.168.1.199:7004> set key2 val2  
8. -> Redirected to slot [4998] located at 192.168.1.199:7003  
9. OK  
10. 192.168.1.199:7003> get key2  
11. "val2"
12. 192.168.1.199:7003>

从中可以发现存时是分布式存储，取时也是从集群中取，测试成功

8、redis cluster 架构

1)redis-cluster架构图

redis集群主从slave调整成master redis集群主从配置_redis