1.redis 集群需要最少 3个master
创建 cluster
redis-cli --cluster create 127.0.0.1:6379 127.0.0.1:6380 127.0.0.1:6381 127.0.0.1:6382 127.0.0.1:6383 127.0.0.1:6384 --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 127.0.0.1:6382 to 127.0.0.1:6379
Adding replica 127.0.0.1:6383 to 127.0.0.1:6380
Adding replica 127.0.0.1:6384 to 127.0.0.1:6381
>>> Trying to optimize slaves allocation for anti-affinity
[WARNING] Some slaves are in the same host as their master
M: dd7a081094f3df3eac846e8c92144636c3b05777 127.0.0.1:6379
slots:[0-5460] (5461 slots) master
M: daa2f0d2d9e0ef853e0c118800d3e8022d008ab5 127.0.0.1:6380
slots:[5461-10922] (5462 slots) master
M: bd1bb520b39298d25acfeb40b347dcaa53e65629 127.0.0.1:6381
slots:[10923-16383] (5461 slots) master
S: 5b01fb6f3bfe3c2472cb351910322de77f09704d 127.0.0.1:6382
replicates daa2f0d2d9e0ef853e0c118800d3e8022d008ab5
S: 873c3f9cbe5742a5bd19fc80ff0012312191283a 127.0.0.1:6383
replicates bd1bb520b39298d25acfeb40b347dcaa53e65629
S: d5d222140c5a3d46c2e69a613ec65281d6759b2b 127.0.0.1:6384
replicates dd7a081094f3df3eac846e8c92144636c3b05777
Can I set the above configuration? (type 'yes' to accept): yes
...
...
9911:C 03 Jun 2019 16:54:00.102 * RDB: 0 MB of memory used by copy-on-write
9085:M 03 Jun 2019 16:54:00.164 * Background saving terminated with success
检查状态
redis-cli --cluster check 127.0.0.1:6379
127.0.0.1:6379 (dd7a0810...) -> 1 keys | 5461 slots | 1 slaves.
127.0.0.1:6380 (daa2f0d2...) -> 2 keys | 5462 slots | 1 slaves.
127.0.0.1:6381 (bd1bb520...) -> 1 keys | 5461 slots | 1 slaves.
[OK] 4 keys in 3 masters.
0.00 keys per slot on average.
>>> Performing Cluster Check (using node 127.0.0.1:6379)
M: dd7a081094f3df3eac846e8c92144636c3b05777 127.0.0.1:6379
slots:[0-5460] (5461 slots) master
1 additional replica(s)
S: 873c3f9cbe5742a5bd19fc80ff0012312191283a 127.0.0.1:6383
slots: (0 slots) slave
replicates bd1bb520b39298d25acfeb40b347dcaa53e65629
S: 5b01fb6f3bfe3c2472cb351910322de77f09704d 127.0.0.1:6382
slots: (0 slots) slave
replicates daa2f0d2d9e0ef853e0c118800d3e8022d008ab5
M: daa2f0d2d9e0ef853e0c118800d3e8022d008ab5 127.0.0.1:6380
slots:[5461-10922] (5462 slots) master
1 additional replica(s)
M: bd1bb520b39298d25acfeb40b347dcaa53e65629 127.0.0.1:6381
slots:[10923-16383] (5461 slots) master
1 additional replica(s)
S: d5d222140c5a3d46c2e69a613ec65281d6759b2b 127.0.0.1:6384
slots: (0 slots) slave
replicates dd7a081094f3df3eac846e8c92144636c3b05777
[OK] All nodes agree about slots configuration.
>>> Check for open slots...
>>> Check slots coverage...
[OK] All 16384 slots covered.
他们都说redis-trib 好，可惜我还不会用~
下面来看redis 集群分布的图，一种分片的主备模式。
image.png
那么用户是怎么访问到不同的master上的数据的呢？代理，当然是代理了，看图[转自：https://juejin.im/post/5b8fc5536fb9a05d2d01fb11]
image.png
