redis3.0 集群实战2 - 集群功能实战

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1 集群基本操作

 

1.1 查看当前集群状态

使用redis-trib.rb check功能查看对应的节点的状态：

[[email protected] bin]# ./redis-trib.rb check 127.0.0.1:7000
Connecting to node 127.0.0.1:7000: OK
Connecting to node 127.0.0.1:7002: OK
Connecting to node 127.0.0.1:7001: OK
Performing Cluster Check (using node 127.0.0.1:7000)
M: 36fce4bf6c829797c433c08b045a8c482e07fbc1 127.0.0.1:7000
   slots:0-5460 (5461 slots) master
   0 additional replica(s)
M: e89c01d7cc2a83f072f66d0c2fb1f5cd92c66888 127.0.0.1:7002
   slots:10923-16383 (5461 slots) master
   0 additional replica(s)
M: 7e46925ca9781a403facf450aa0b4b8149ad9c27 127.0.0.1:7001
   slots:5461-10922 (5462 slots) master
   0 additional replica(s)
[OK] All nodes agree about slots configuration.
    Check for open slots...
    Check slots coverage...
[OK] All 16384 slots covered.

　　

如上图所示，当前我们有三个节点7000到7002，默认总共16384个slot，平均一个节点5461个slot

或者我们也可以使用redis-cli连接上任意一个结点，执行cluster nodes查看结点状态：

[[email protected] bin]# ./redis-cli -c -p 7000 cluster nodes
e89c01d7cc2a83f072f66d0c2fb1f5cd92c66888 127.0.0.1:7002 master - 0 1440144105378 3 connected 10923-16383
36fce4bf6c829797c433c08b045a8c482e07fbc1 127.0.0.1:7000 myself,master - 0 0 1 connected 0-5460
7e46925ca9781a403facf450aa0b4b8149ad9c27 127.0.0.1:7001 master - 0 1440144106398 2 connected 5461-10922

1.2 增加一个主节点

1 启动7003的redis实例：

[[email protected] bin]# ps aux | grep redis
root       4212  0.1  0.1 140836  7252 ?        Ssl  Aug20   0:41 ./redis-server *:7000 [cluster]
root       4214  0.1  0.1 140836  7296 ?        Ssl  Aug20   0:41 ./redis-server *:7001 [cluster]
root       4218  0.1  0.1 140836  7228 ?        Ssl  Aug20   0:41 ./redis-server *:7002 [cluster]
root      10817  0.0  0.1  20160  5180 pts/0    S+   00:41   0:00 ./redis-cli -c -p 7000
root      11223  0.0  0.1 140836  7460 ?        Ssl  00:54   0:00 ./redis-server *:7003 [cluster]

　　

2 使用 redis-cli cluster nodes查看当前集群状态，跟1.1一样，7003实例还没加进来

[[email protected] bin]# ./redis-cli -c -p 7000 cluster nodes
e89c01d7cc2a83f072f66d0c2fb1f5cd92c66888 127.0.0.1:7002 master - 0 1440144105378 3 connected 10923-16383
36fce4bf6c829797c433c08b045a8c482e07fbc1 127.0.0.1:7000 myself,master - 0 0 1 connected 0-5460
7e46925ca9781a403facf450aa0b4b8149ad9c27 127.0.0.1:7001 master - 0 1440144106398 2 connected 5461-10922

　　

3 使用redis-trib.rb add-node增加结点

[[email protected] bin]# ./redis-trib.rb add-node 127.0.0.1:7003 127.0.0.1:7000
    Adding node 127.0.0.1:7003 to cluster 127.0.0.1:7000
    Connecting to node 127.0.0.1:7000: OK
    Connecting to node 127.0.0.1:7002: OK
    Connecting to node 127.0.0.1:7001: OK
    Performing Cluster Check (using node 127.0.0.1:7000)
M: 36fce4bf6c829797c433c08b045a8c482e07fbc1 127.0.0.1:7000
   slots:0-5460 (5461 slots) master
   0 additional replica(s)
M: e89c01d7cc2a83f072f66d0c2fb1f5cd92c66888 127.0.0.1:7002
   slots:10923-16383 (5461 slots) master
   0 additional replica(s)
M: 7e46925ca9781a403facf450aa0b4b8149ad9c27 127.0.0.1:7001
   slots:5461-10922 (5462 slots) master
   0 additional replica(s)
[OK] All nodes agree about slots configuration.
    Check for open slots...
    Check slots coverage...
[OK] All 16384 slots covered.
Connecting to node 127.0.0.1:7003: OK
    Send CLUSTER MEET to node 127.0.0.1:7003 to make it join the cluster.
[OK] New node added correctly.

　　

4 使用redis-cli查看当前cluster的状态

[[email protected] bin]# ./redis-cli -c -p 7000 cluster nodes
    245d95199dcc1e01880b2876fcab8a75b1867b19 127.0.0.1:7003 master - 0 1440144104360 0 connected
    e89c01d7cc2a83f072f66d0c2fb1f5cd92c66888 127.0.0.1:7002 master - 0 1440144105378 3 connected 10923-16383
    36fce4bf6c829797c433c08b045a8c482e07fbc1 127.0.0.1:7000 myself,master - 0 0 1 connected 0-5460
    7e46925ca9781a403facf450aa0b4b8149ad9c27 127.0.0.1:7001 master - 0 1440144106398 2 connected 5461-10922

　　

发现新节点已经连上cluster了，成为集群一份子，并且默认是master结点。这时候，我们已经可以使用redis-cli连接到该结点查询情况

[[email protected] bin]# ./redis-cli -c -p 7003
127.0.0.1:7003> set a b
-> Redirected to slot [15495] located at 127.0.0.1:7002
OK
127.0.0.1:7002>

　　

不过redis cluster并不会自动把hash分片迁移到该结点

5 使用redis-trib.rb rehashed重新设置分片

- ./redis-trib.rb reshard 127.0.0.1:7003执行rehash
- 需要再命令行中输入slots个数（迁移的slots数目）
- 需要填写迁移目标结点的id，这里我们希望迁移到7003上，所以把7003的id写上去（通过redis-cli cluster nodes查看对应id）
- 需要填写source node，可以填上对应的source节点id，或者写all，表示从所有节点中抽取1000个出来，这里写all
- 这里redis集群会列出来模拟迁移的点，确认后，填写yes，那么开始进行实例迁移

6 查看新的分片

127.0.0.1:7000> cluster nodes
    245d95199dcc1e01880b2876fcab8a75b1867b19 127.0.0.1:7003 master - 0 1440145009719 4 connected 0-332 5461-5794 10923-11255
    e89c01d7cc2a83f072f66d0c2fb1f5cd92c66888 127.0.0.1:7002 master - 0 1440145009206 3 connected 11256-16383
    36fce4bf6c829797c433c08b045a8c482e07fbc1 127.0.0.1:7000 myself,master - 0 0 1 connected 333-5460
    7e46925ca9781a403facf450aa0b4b8149ad9c27 127.0.0.1:7001 master - 0 1440145010228 2 connected 5795-10922

　　

如上所示，可以看出，7003从剩余3个节点中抽取除了1000个slots出来，整体上抽取的相对比较均匀

 

1.3 增加一个从节点

1 启动7004的redis实例

[[email protected] bin]# ps aux | grep redis
root       4212  0.1  0.1 140836  7240 ?        Ssl  Aug20   0:46 ./redis-server *:7000 [cluster]
root       4214  0.1  0.1 140836  7296 ?        Ssl  Aug20   0:46 ./redis-server *:7001 [cluster]
root       4218  0.1  0.1 140836  7292 ?        Ssl  Aug20   0:46 ./redis-server *:7002 [cluster]
root      10817  0.0  0.1  20160  5192 pts/0    S+   00:41   0:00 ./redis-cli -c -p 7000
root      11223  0.2  0.1 140836  7356 ?        Ssl  00:54   0:05 ./redis-server *:7003     [cluster]
root      12063  0.2  0.1 140836  7464 ?        Ssl  01:34   0:00 ./redis-server *:7004 [cluster]

　　

2 使用redis-trib.rb add-node增加7004节点

[[email protected] bin]# ./redis-trib.rb add-node 127.0.0.1:7004 127.0.0.1:7000
Adding node 127.0.0.1:7004 to cluster 127.0.0.1:7000
Connecting to node 127.0.0.1:7000: OK
Connecting to node 127.0.0.1:7002: OK
Connecting to node 127.0.0.1:7003: OK
Connecting to node 127.0.0.1:7001: OK
Performing Cluster Check (using node 127.0.0.1:7000)
M: 36fce4bf6c829797c433c08b045a8c482e07fbc1 127.0.0.1:7000 slots:333-5460 (5128 slots) master 0 additional replica(s)
M: e89c01d7cc2a83f072f66d0c2fb1f5cd92c66888 127.0.0.1:7002 slots:11256-16383 (5128 slots) master 0 additional replica(s)
M: 245d95199dcc1e01880b2876fcab8a75b1867b19 127.0.0.1:7003 slots:0-332,5461-5794,10923-11255 (1000 slots) master 0 additional replica(s)
M: 7e46925ca9781a403facf450aa0b4b8149ad9c27 127.0.0.1:7001 slots:5795-10922 (5128 slots) master 0 additional replica(s)

　　

[OK] All nodes agree about slots configuration. Check for open slots... Check slots coverage... [OK] All 16384 slots covered. Connecting to node 127.0.0.1:7004: OK Send CLUSTER MEET to node 127.0.0.1:7004 to make it join the cluster. [OK] New node added correctly.

3 查看当前集群nodes状态

[[email protected] bin]# ./redis-cli -c -p 7000 cluster nodes
36fce4bf6c829797c433c08b045a8c482e07fbc1 127.0.0.1:7000 myself,master - 0 0 1 connected 333-5460
e89c01d7cc2a83f072f66d0c2fb1f5cd92c66888 127.0.0.1:7002 master - 0 1440147387481 3 connected 11256-16383
245d95199dcc1e01880b2876fcab8a75b1867b19 127.0.0.1:7003 master - 0 1440147389014 4 connected 0-332 5461-5794 10923-11255
f26de43ddafc2e8e000132c3b53473d42906b429 127.0.0.1:7004 master - 0 1440147387991 0 connected
7e46925ca9781a403facf450aa0b4b8149ad9c27 127.0.0.1:7001 master - 0 1440147388501 2 connected 5795-10922

　　

默认在增加节点的时候都是master节点，因此刚加进去的7004节点也是master

4 将7004转成7001的slave节点





# 使用redis-cli连接到7004上，查看当前node的状态


[[email protected] bin]# ./redis-cli -p 7004 -c
127.0.0.1:7004> cluster nodes
    f26de43ddafc2e8e000132c3b53473d42906b429 127.0.0.1:7004 myself,master - 0 0 0 connected
    245d95199dcc1e01880b2876fcab8a75b1867b19 127.0.0.1:7003 master - 0 1440147476431 4 connected 0-332 5461-5794 10923-11255
    36fce4bf6c829797c433c08b045a8c482e07fbc1 127.0.0.1:7000 master - 0 1440147476944 1 connected 333-5460
    7e46925ca9781a403facf450aa0b4b8149ad9c27 127.0.0.1:7001 master - 0 1440147477452 2 connected 5795-10922
    e89c01d7cc2a83f072f66d0c2fb1f5cd92c66888 127.0.0.1:7002 master - 0 1440147475924 3 connected 11256-16383



# 使用cluster replicate <id>命令将7004设置为7001的从节点，其中id为7001的节点id
127.0.0.1:7004> cluster replicate 7e46925ca9781a403facf450aa0b4b8149ad9c27
OK

# 再次查看cluster nodes
127.0.0.1:7004> cluster nodes
    f26de43ddafc2e8e000132c3b53473d42906b429 127.0.0.1:7004 myself,slave 7e46925ca9781a403facf450aa0b4b8149ad9c27 0 0 0 connected
    245d95199dcc1e01880b2876fcab8a75b1867b19 127.0.0.1:7003 master - 0 1440147500851 4 connected 0-332 5461-5794 10923-11255
    36fce4bf6c829797c433c08b045a8c482e07fbc1 127.0.0.1:7000 master - 0 1440147499834 1 connected 333-5460
    7e46925ca9781a403facf450aa0b4b8149ad9c27 127.0.0.1:7001 master - 0 1440147500849 2 connected 5795-10922
    e89c01d7cc2a83f072f66d0c2fb1f5cd92c66888 127.0.0.1:7002 master - 0 1440147500338 3 connected 11256-16383

# 当前7004已经成功成为7001的从节点了








1.4 主从自动切换


    

  1. 

    查看当前集群状态
    

    

    [[email protected] bin]# ./redis-cli -p 7000 -c cluster nodes
36fce4bf6c829797c433c08b045a8c482e07fbc1 127.0.0.1:7000 myself,master - 0 0 5 connected 0-5794 10923-11255
e89c01d7cc2a83f072f66d0c2fb1f5cd92c66888 127.0.0.1:7002 master - 0 1440402734058 3 connected 11256-16383
245d95199dcc1e01880b2876fcab8a75b1867b19 127.0.0.1:7003 slave 36fce4bf6c829797c433c08b045a8c482e07fbc1 0 1440402733548 5 connected
f26de43ddafc2e8e000132c3b53473d42906b429 127.0.0.1:7004 slave 7e46925ca9781a403facf450aa0b4b8149ad9c27 0 1440402734573 2 connected
7e46925ca9781a403facf450aa0b4b8149ad9c27 127.0.0.1:7001 master - 0 1440402735085 2 connected 5795-10922
    

    

    如图所示，当前7000,7001,7002三个为主，7003为7000的slave，7004位7001的slave
    

    2. 

  2. 

    构造数据
    

    

    # 构造数据
for ((i=0;i<1000;i++)); do ./redis-cli -p 7000 -c set "key$i" "$i";done

# 查看数据分片情况：
[[email protected] bin]# ./redis-cli -p 7000 -c dbsize
    (integer) 369
[[email protected] bin]# ./redis-cli -p 7001 -c dbsize
    (integer) 316
[[email protected] bin]# ./redis-cli -p 7002 -c dbsize
    (integer) 316

# 发现基本上比较均匀1000个key平均分到三个分片上了

    

    

    　　
    

    3. 

  3. 

    kill主节点
    

    

    # 我们把7000的redis-server kill掉，看看是否能自动迁移到7003
[[email protected] bin]# ps aux | grep redis | grep 7000
root      11223  0.2  0.2 140836  9408 ?        Ssl  Aug23   0:47 ./redis-server *:7000 [cluster]
[[email protected] bin]# kill -9 11223
[[email protected] bin]# ps aux | grep redis 
root       4212  0.2  0.2 140836  9196 ?        Ssl  Aug23   1:27 ./redis-server *:7003 [cluster]
root       4214  0.2  0.1 140836  7412 ?        Ssl  Aug23   1:27 ./redis-server *:7001 [cluster]
root       4218  0.2  0.1 140836  7352 ?        Ssl  Aug23   1:26 ./redis-server *:7002 [cluster]
root      12649  0.2  0.2 140836  9552 ?        Ssl  Aug23   0:39 ./redis-server *:7004 [cluster]

    

    

    　　
    

    4. 

  4. 

    查看当前节点状态
    

    

    [[email protected] bin]# ./redis-cli -p 7001 -c cluster nodes
    f26de43ddafc2e8e000132c3b53473d42906b429 127.0.0.1:7004 slave 7e46925ca9781a403facf450aa0b4b8149ad9c27 0 1440403755252 2 connected
    7e46925ca9781a403facf450aa0b4b8149ad9c27 127.0.0.1:7001 myself,master - 0 0 2 connected 5795-10922
    36fce4bf6c829797c433c08b045a8c482e07fbc1 127.0.0.1:7000 master,fail - 1440403749785 1440403749179 5 disconnected
    245d95199dcc1e01880b2876fcab8a75b1867b19 127.0.0.1:7003 master - 0 1440403756767 6 connected 0-5794 10923-11255
    e89c01d7cc2a83f072f66d0c2fb1f5cd92c66888 127.0.0.1:7002 master - 0 1440403756260 3 connected 11256-16383

# 发现7003已经自动成为主了

    

    

    　　
    

    5. 

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