官方文檔地址：https://redis.io/topics/cluster-tutorial
本例 Redis 版本 5.0.5
安裝目錄/home/shaw/server/redis5/；
若有不懂，請結合 Redis 官方文檔
集羣需要依賴到 Ruby，因此需確保已經安裝 Ruby：
sudo apt-get install ruby
gem install redis
集羣 redis.conf 最簡配置示例
# Redis 服務端口號
port 7001
# 啓動集羣
cluster-enabled yes
# 集羣配置文件
cluster-config-file nodes.conf
# 集羣超時時間
cluster-node-timeout 15000
appendonly yes
進入 Redis 安裝目錄 bin/
cd /home/shaw/server/redis5/bin/
創建集羣 Redis 的 redis.conf 配置文件
cd /home/shaw/server/redis5/bin/
mkdir cluster-test/
cd cluster-test/
mkdir 7001/ 7002/ 7003/ 7004/ 7005/ 7006/ 7007/ 7008/ 7009/
爲 7001/ 到 7009/ 目錄創建 redis.conf 文件
cd 7001/
../redis-server ./redis.conf
搭建集羣
# Redis 5.0 起版本搭建集羣命令；
sudo ./redis-cli --cluster create 127.0.0.1:7001 127.0.0.1:7002 127.0.0.1:7003 127.0.0.1:7004 127.0.0.1:7005 127.0.0.1:7006 127.0.0.1:7007 127.0.0.1:7008 127.0.0.1:7009 --cluster-replicas 2
# 注：--cluster-replicas 2 表示從服務器數量與主服務器數量的比值，例如：
# 三主三從則 --cluster-replicas 1
# 三主六從則 --cluster-replicas 2
# Redis 3 4 版本創建一個新的集羣命令
./redis-trib.rb create --replicas 1 127.0.0.1:7001 127.0.0.1:7002 127.0.0.1:7003 127.0.0.1:7004 127.0.0.1:7005 127.0.0.1:7006
# 選項 --replicas 1 表示我們希望爲集羣中的每個主節點創建一個從節點
接下來 redis-cli 會打印一份預想中的配置給你看，例如：
>>> Performing hash slots allocation on 9 nodes...
Master[0] -> Slots 0 - 5460
Master[1] -> Slots 5461 - 10922
Master[2] -> Slots 10923 - 16383
Adding replica 127.0.0.1:7005 to 127.0.0.1:7001
Adding replica 127.0.0.1:7006 to 127.0.0.1:7001
Adding replica 127.0.0.1:7007 to 127.0.0.1:7002
Adding replica 127.0.0.1:7008 to 127.0.0.1:7002
Adding replica 127.0.0.1:7009 to 127.0.0.1:7003
Adding replica 127.0.0.1:7004 to 127.0.0.1:7003
>>> Trying to optimize slaves allocation for anti-affinity
[WARNING] Some slaves are in the same host as their master
M: 9a8f09ce4fcf09c6c461faf6d5c59ace86424ab6 127.0.0.1:7001
slots:[0-5460] (5461 slots) master
M: 308c7986b97355287c692b8b6fb82212d5713f3e 127.0.0.1:7002
slots:[5461-10922] (5462 slots) master
M: 73fd1439c3470a8d815e3e1c299a80ceee189965 127.0.0.1:7003
slots:[10923-16383] (5461 slots) master
S: faa15fa024cbb0321d69f8475794b8715a786697 127.0.0.1:7004
replicates 9a8f09ce4fcf09c6c461faf6d5c59ace86424ab6
S: b6032c4949d0f1efa278ffa13871132c4234832c 127.0.0.1:7005
replicates 308c7986b97355287c692b8b6fb82212d5713f3e
S: 1623ed56e018724d318f40606952d8783560a296 127.0.0.1:7006
replicates 73fd1439c3470a8d815e3e1c299a80ceee189965
S: 9dbc952683eb73bacd4970f2d1a89d66d2bd2f21 127.0.0.1:7007
replicates 308c7986b97355287c692b8b6fb82212d5713f3e
S: 0f69b47538a2ef7a3b06b83454c6ecad2a6107bc 127.0.0.1:7008
replicates 73fd1439c3470a8d815e3e1c299a80ceee189965
S: ff326b6bcca10e3641ae5ea99b96fc94697fdcc2 127.0.0.1:7009
replicates 9a8f09ce4fcf09c6c461faf6d5c59ace86424ab6
Can I set the above configuration? (type 'yes' to accept): yes
沒有問題的話輸入 yes 並回車即可，配置成功後能看到如下提示：
>>> 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 127.0.0.1:7001)
M: 9a8f09ce4fcf09c6c461faf6d5c59ace86424ab6 127.0.0.1:7001
slots:[0-5460] (5461 slots) master
2 additional replica(s)
S: faa15fa024cbb0321d69f8475794b8715a786697 127.0.0.1:7004
slots: (0 slots) slave
replicates 9a8f09ce4fcf09c6c461faf6d5c59ace86424ab6
S: b6032c4949d0f1efa278ffa13871132c4234832c 127.0.0.1:7005
slots: (0 slots) slave
replicates 308c7986b97355287c692b8b6fb82212d5713f3e
M: 73fd1439c3470a8d815e3e1c299a80ceee189965 127.0.0.1:7003
slots:[10923-16383] (5461 slots) master
2 additional replica(s)
S: 9dbc952683eb73bacd4970f2d1a89d66d2bd2f21 127.0.0.1:7007
slots: (0 slots) slave
replicates 308c7986b97355287c692b8b6fb82212d5713f3e
S: 1623ed56e018724d318f40606952d8783560a296 127.0.0.1:7006
slots: (0 slots) slave
replicates 73fd1439c3470a8d815e3e1c299a80ceee189965
S: 0f69b47538a2ef7a3b06b83454c6ecad2a6107bc 127.0.0.1:7008
slots: (0 slots) slave
replicates 73fd1439c3470a8d815e3e1c299a80ceee189965
M: 308c7986b97355287c692b8b6fb82212d5713f3e 127.0.0.1:7002
slots:[5461-10922] (5462 slots) master
2 additional replica(s)
S: ff326b6bcca10e3641ae5ea99b96fc94697fdcc2 127.0.0.1:7009
slots: (0 slots) slave
replicates 9a8f09ce4fcf09c6c461faf6d5c59ace86424ab6
[OK] All nodes agree about slots configuration.
>>> Check for open slots...
>>> Check slots coverage...
[OK] All 16384 slots covered.
其中 [OK] All 16384 slots covered. 表示集羣中的 16384 個槽都有至少一個主節點在處理， 集羣運作正常。
使用 redis-cli 檢測集羣功能；
$ ./redis-cli -c -p 7001
127.0.0.1:7001> set foo bar
-> Redirected to slot [12182] located at 127.0.0.1:7003
OK
127.0.0.1:7003> set hello world
-> Redirected to slot [866] located at 127.0.0.1:7001
OK
127.0.0.1:7001> get foo
-> Redirected to slot [12182] located at 127.0.0.1:7003
"bar"
127.0.0.1:7003> get hello
-> Redirected to slot [866] located at 127.0.0.1:7001
"world"
127.0.0.1:7001>
查看集羣節點
./redis-cli -p 7001 cluster nodes
73fd1439c3470a8d815e3e1c299a80ceee189965 127.0.0.1:7003@17003 master - 0 1559721805000 3 connected 10923-16383
b6032c4949d0f1efa278ffa13871132c4234832c 127.0.0.1:7005@17005 slave 308c7986b97355287c692b8b6fb82212d5713f3e 0 1559721803000 5 connected
9dbc952683eb73bacd4970f2d1a89d66d2bd2f21 127.0.0.1:7007@17007 slave 308c7986b97355287c692b8b6fb82212d5713f3e 0 1559721806769 7 connected
9a8f09ce4fcf09c6c461faf6d5c59ace86424ab6 127.0.0.1:7001@17001 myself,master - 0 1559721803000 1 connected 0-5460
faa15fa024cbb0321d69f8475794b8715a786697 127.0.0.1:7004@17004 slave 9a8f09ce4fcf09c6c461faf6d5c59ace86424ab6 0 1559721805000 4 connected
1623ed56e018724d318f40606952d8783560a296 127.0.0.1:7006@17006 slave 73fd1439c3470a8d815e3e1c299a80ceee189965 0 1559721804756 6 connected
0f69b47538a2ef7a3b06b83454c6ecad2a6107bc 127.0.0.1:7008@17008 slave 73fd1439c3470a8d815e3e1c299a80ceee189965 0 1559721803000 8 connected
ff326b6bcca10e3641ae5ea99b96fc94697fdcc2 127.0.0.1:7009@17009 slave 9a8f09ce4fcf09c6c461faf6d5c59ace86424ab6 0 1559721805764 9 connected
308c7986b97355287c692b8b6fb82212d5713f3e 127.0.0.1:7002@17002 master - 0 1559721803000 2 connected 5461-10922
添加一個新的主節點
./redis-cli --cluster add-node 127.0.0.1:7011 127.0.0.1:7001
./redis-cli -p 7001 cluster nodes | grep master
73fd1439c3470a8d815e3e1c299a80ceee189965 127.0.0.1:7003@17003 master - 0 1559724583000 3 connected 10923-16383
9a8f09ce4fcf09c6c461faf6d5c59ace86424ab6 127.0.0.1:7001@17001 myself,master - 0 1559724574000 1 connected 0-5460
# 其他都有分配到哈希槽，而 127.0.0.1:7011@17011 沒有；
28c02cdcf91e19c808213c386741f8cf2391c00c 127.0.0.1:7011@17011 master - 0 1559724581723 0 connected
308c7986b97355287c692b8b6fb82212d5713f3e 127.0.0.1:7002@17002 master - 0 1559724582000 2 connected 5461-10922
新節點現在已經連接上了集羣， 成爲集羣的一份子， 並且可以對客戶端的命令請求進行轉向了， 但是和其他主節點相比， 新節點還有兩點區別：
- 新節點沒有包含任何數據， 因爲它沒有包含任何哈希槽.
- 儘管新節點沒有包含任何哈希槽， 但它仍然是一個主節點， 所以在集羣需要將某個從節點升級爲新的主節點時， 這個新節點不會被選中。
重新分配
./redis-cli --cluster reshard 127.0.0.1:7001
添加一個從節點
方法一：
# 添加節點 7010 並將其設置爲 7001 的子節點
./redis-cli --cluster add-node 127.0.0.1:7010 127.0.0.1:7001 --cluster-slave
方法二：
# 添加節點 7010 並將其設置爲 7001 的子節點
./redis-cli --cluster add-node 127.0.0.1:7010 127.0.0.1:7001 --cluster-slave --cluster-master-id 9a8f09ce4fcf09c6c461faf6d5c59ace86424ab6
移除一個節點
只要使用 del-node 命令即可
./redis-cli --cluster del-node 127.0.0.1:7001 `<node-id>`