Redis Cluster集群
Redis Cluster集群
一、redis-cluster设计
Redis集群搭建的方式有多种,例如使用zookeeper等,但从redis 3.0之后版本支持redis-cluster集群,Redis-Cluster采用无中心结构,每个节点保存数据和整个集群状态,每个节点都和其他所有 节点连接。其redis-cluster架构图如下:
其结构特点:
1、所有的redis节点彼此互联(PING-PONG机制),内部使用二进制协议优化传输速度和带宽。
2、节点的fail是通过集群中超过半数的节点检测失效时才生效。
3、客户端与redis节点直连,不需要中间proxy层.客户端不需要连接集群所有节点,连接集群中任何一个可用节点即可。
4、redis-cluster把所有的物理节点映射到[0-16383]slot上(不一定是平均分配),cluster 负责维护node<->slot<->value。
5、Redis集群预分好16384个桶,当需要在 Redis 集群中放置一个 key-value 时,根据 CRC16(key) mod 16384的值,决定将一个key放到哪个桶中。
1、redis cluster节点分配
现在我们是三个主节点分别是:A, B, C 三个节点,它们可以是一台机器上的三个端口,也可以是三台不同的服务器。那么,采用哈希槽 (hash slot)的方式来分配16384个slot 的话,它们三个节点分别承担的slot 区间是:
节点A覆盖0-5460;
节点B覆盖5461-10922;
节点C覆盖10923-16383.
获取数据:
如果存入一个值,按照redis cluster哈希槽的算法: CRC16('key')%16384 = 6782。 那么就会把这个key 的存储分配到 B 上了。同样,当我连接(A,B,C)任何一个节点想获取'key'这个key时,也会这样的算法,然后内部跳转到B节点上获取数据
新增一个主节点:
新增一个节点D,redis cluster的这种做法是从各个节点的前面各拿取一部分slot到D上,我会在接下来的实践中实验。大致就会变成这样:
节点A覆盖1365-5460
节点B覆盖6827-10922
节点C覆盖12288-16383
节点D覆盖0-1364,5461-6826,10923-12287
同样删除一个节点也是类似,移动完成后就可以删除这个节点了。
2、Redis Cluster主从模式
redis cluster 为了保证数据的高可用性,加入了主从模式,一个主节点对应一个或多个从节点,主节点提供数据存取,从节点则是从主节点拉取数据备份,当这个主节点挂掉后,就会有这个从节点选取一个来充当主节点,从而保证集群不会挂掉。
上面那个例子里, 集群有ABC三个主节点, 如果这3个节点都没有加入从节点,如果B挂掉了,我们就无法访问整个集群了。A和C的slot也无法访问。
所以我们在集群建立的时候,一定要为每个主节点都添加了从节点, 比如像这样, 集群包含主节点A、B、C, 以及从节点A1、B1、C1, 那么即使B挂掉系统也可以继续正确工作。
B1节点替代了B节点,所以Redis集群将会选择B1节点作为新的主节点,集群将会继续正确地提供服务。 当B重新开启后,它就会变成B1的从节点。
不过需要注意,如果节点B和B1同时挂了,Redis集群就无法继续正确地提供服务了。
二、redis集群的搭建
集群中至少应该有奇数个节点,所以至少有三个节点,每个节点至少有一个备份节点,所以下面使用6节点(主节点、备份节点由redis-cluster集群确定)。
下面使用redis-3.2.0安装,下载地址
1、安装redis节点指定端口
解压redis压缩包,编译安装
- [root@localhost redis-3.2.0]# tar xzf redis-3.2.0.tar.gz
- [root@localhost redis-3.2.0]# cd redis-3.2.0
- [root@localhost redis-3.2.0]# make
- [root@localhost redis01]# make install PREFIX=/usr/andy/redis-cluster
在redis-cluster下 修改bin文件夹为redis01,复制redis.conf配置文件
配置redis的配置文件redis.conf
daemonize yes #后台启动
port 7001 #修改端口号,从7001到7006
cluster-enabled yes #开启cluster,去掉注释
cluster-config-file nodes.conf
cluster-node-timeout 15000
appendonly yes
复制六份,修改对应的端口号
2、安装redis-trib所需的 ruby脚本
复制redis解压文件src下的redis-trib.rb文件到redis-cluster目录
- [root@localhost redis-cluster]# cp /usr/andy/redis/redis-3.2.0/src/redis-trib.rb ./
安装ruby环境:
- [root@localhost redis-cluster]# yum install ruby
- [root@localhost redis-cluster]# yum install rubygems
安装redis-trib.rb运行依赖的ruby的包redis-3.2.2.gem,下载
- [root@localhost redis-cluster]# gem install redis-3.2.2.gem
3、启动所有的redis节点
可以写一个命令脚本start-all.sh
- cd redis01
- ./redis-server redis.conf
- cd ..
- cd redis02
- ./redis-server redis.conf
- cd ..
- cd redis03
- ./redis-server redis.conf
- cd ..
- cd redis04
- ./redis-server redis.conf
- cd ..
- cd redis05
- ./redis-server redis.conf
- cd ..
- cd redis06
- ./redis-server redis.conf
- cd ..
设置权限启动
- [root@localhost redis-cluster]# chmod 777 start-all.sh
- [root@localhost redis-cluster]# ./start-all.sh
查看redis进程启动状态
- [root@localhost redis-cluster]# ps -ef | grep redis
- root 4547 1 0 23:12 ? 00:00:00 ./redis-server 127.0.0.1:7001 [cluster]
- root 4551 1 0 23:12 ? 00:00:00 ./redis-server 127.0.0.1:7002 [cluster]
- root 4555 1 0 23:12 ? 00:00:00 ./redis-server 127.0.0.1:7003 [cluster]
- root 4559 1 0 23:12 ? 00:00:00 ./redis-server 127.0.0.1:7004 [cluster]
- root 4563 1 0 23:12 ? 00:00:00 ./redis-server 127.0.0.1:7005 [cluster]
- root 4567 1 0 23:12 ? 00:00:00 ./redis-server 127.0.0.1:7006 [cluster]
- root 4840 4421 0 23:26 pts/1 00:00:00 grep --color=auto redis
可以看到redis的6个节点已经启动成功
杀死全部的几点:
- [root@localhost redis-cluster]# pkill -9 redis
4、使用redis-trib.rb创建集群
- ./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
使用create命令 --replicas 1 参数表示为每个主节点创建一个从节点,其他参数是实例的地址集合。
- [root@localhost redis-cluster]# ./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
- >>> Creating cluster
- >>> Performing hash slots allocation on 6 nodes...
- Using 3 masters:
- 127.0.0.1:7001
- 127.0.0.1:7002
- 127.0.0.1:7003
- Adding replica 127.0.0.1:7004 to 127.0.0.1:7001
- Adding replica 127.0.0.1:7005 to 127.0.0.1:7002
- Adding replica 127.0.0.1:7006 to 127.0.0.1:7003
- M: dfd510594da614469a93a0a70767ec9145aefb1a 127.0.0.1:7001
- slots:0-5460 (5461 slots) master
- M: e02eac35110bbf44c61ff90175e04d55cca097ff 127.0.0.1:7002
- slots:5461-10922 (5462 slots) master
- M: 4385809e6f4952ecb122dbfedbee29109d6bb234 127.0.0.1:7003
- slots:10923-16383 (5461 slots) master
- S: ec02c9ef3acee069e8849f143a492db18d4bb06c 127.0.0.1:7004
- replicates dfd510594da614469a93a0a70767ec9145aefb1a
- S: 83e5a8bb94fb5aaa892cd2f6216604e03e4a6c75 127.0.0.1:7005
- replicates e02eac35110bbf44c61ff90175e04d55cca097ff
- S: 10c097c429ca24f8720986c6b66f0688bfb901ee 127.0.0.1:7006
- replicates 4385809e6f4952ecb122dbfedbee29109d6bb234
- 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 127.0.0.1:7001)
- M: dfd510594da614469a93a0a70767ec9145aefb1a 127.0.0.1:7001
- slots:0-5460 (5461 slots) master
- M: e02eac35110bbf44c61ff90175e04d55cca097ff 127.0.0.1:7002
- slots:5461-10922 (5462 slots) master
- M: 4385809e6f4952ecb122dbfedbee29109d6bb234 127.0.0.1:7003
- slots:10923-16383 (5461 slots) master
- M: ec02c9ef3acee069e8849f143a492db18d4bb06c 127.0.0.1:7004
- slots: (0 slots) master
- replicates dfd510594da614469a93a0a70767ec9145aefb1a
- M: 83e5a8bb94fb5aaa892cd2f6216604e03e4a6c75 127.0.0.1:7005
- slots: (0 slots) master
- replicates e02eac35110bbf44c61ff90175e04d55cca097ff
- M: 10c097c429ca24f8720986c6b66f0688bfb901ee 127.0.0.1:7006
- slots: (0 slots) master
- replicates 4385809e6f4952ecb122dbfedbee29109d6bb234
- [OK] All nodes agree about slots configuration.
- >>> Check for open slots...
- >>> Check slots coverage...
- [OK] All 16384 slots covered.
上面显示创建成功,有3个主节点,3个从节点,每个节点都是成功连接状态。
3个主节点[M]以及分配的哈希卡槽如下:
M: dfd510594da614469a93a0a70767ec9145aefb1a 127.0.0.1:7001
slots:0-5460 (5461 slots) master
M: e02eac35110bbf44c61ff90175e04d55cca097ff 127.0.0.1:7002
slots:5461-10922 (5462 slots) master
M: 4385809e6f4952ecb122dbfedbee29109d6bb234 127.0.0.1:7003
slots:10923-16383 (5461 slots) master
3个从节点[S]以及附属的主节点如下:
S: ec02c9ef3acee069e8849f143a492db18d4bb06c 127.0.0.1:7004
replicates dfd510594da614469a93a0a70767ec9145aefb1a
S: 83e5a8bb94fb5aaa892cd2f6216604e03e4a6c75 127.0.0.1:7005
replicates e02eac35110bbf44c61ff90175e04d55cca097ff
S: 10c097c429ca24f8720986c6b66f0688bfb901ee 127.0.0.1:7006
replicates 4385809e6f4952ecb122dbfedbee29109d6bb234
以上集群安装成功了,如果安装未成功报如下错误
>>> Creating cluster
[ERR] Sorry, can't connect to node ....
需要安装最新的ruby源码,下载
- [root@localhost redis-cluster]# tar -zxvf ruby-2.3.1.tar.gz
- [root@localhost redis-cluster]# cd
- [root@localhost redis-cluster]# ./configure --prefix=/usr/local/ruby-2.3.1
- [root@localhost redis-cluster]# make && make install
- [root@localhost redis-cluster]#gem install redis
还有一种情况是,在VMware做测试的时间(都在一台服务器时),ip应该使用127.0.0.1,如果使用局域网ip,也会报节点创建失败。
三、redis集群的测试
1、测试存取值
客户端连接集群redis-cli需要带上 -c ,redis-cli -c -p 端口号
- [root@localhost redis01]# ./redis-cli -c -p 7001
- 127.0.0.1:7001> set name andy
- -> Redirected to slot [5798] located at 127.0.0.1:7002
- OK
- 127.0.0.1:7002> get name
- "andy"
- 127.0.0.1:7002>
根据redis-cluster的key值分配,name应该分配到节点7002[5461-10922]上,上面显示redis cluster自动从7001跳转到了7002节点。
我们可以测试一下7006从节点获取name值
- [root@localhost redis06]# ./redis-cli -c -p 7006
- 127.0.0.1:7006> get name
- -> Redirected to slot [5798] located at 127.0.0.1:7002
- "andy"
- 127.0.0.1:7002>
7006位7003的从节点,从上面也是自动跳转至7002获取值,这也是redis cluster的特点,它是去中心化,每个节点都是对等的,连接哪个节点都可以获取和设置数据。
四、集群节点选举
现在模拟将7002节点挂掉,按照redis-cluster原理会选举会将 7002的从节点7005选举为主节点。
- [root@localhost redis-cluster]# ps -ef | grep redis
- root 7950 1 0 12:50 ? 00:00:28 ./redis-server 127.0.0.1:7001 [cluster]
- root 7952 1 0 12:50 ? 00:00:29 ./redis-server 127.0.0.1:7002 [cluster]
- root 7956 1 0 12:50 ? 00:00:29 ./redis-server 127.0.0.1:7003 [cluster]
- root 7960 1 0 12:50 ? 00:00:29 ./redis-server 127.0.0.1:7004 [cluster]
- root 7964 1 0 12:50 ? 00:00:29 ./redis-server 127.0.0.1:7005 [cluster]
- root 7966 1 0 12:50 ? 00:00:29 ./redis-server 127.0.0.1:7006 [cluster]
- root 11346 10581 0 14:57 pts/2 00:00:00 grep --color=auto redis
- [root@localhost redis-cluster]# kill 7952
在查看集群中的7002节点
- [root@localhost redis-cluster]#
- [root@localhost redis-cluster]# ./redis-trib.rb check 127.0.0.1:7002
- [ERR] Sorry, can't connect to node 127.0.0.1:7002
- [root@localhost redis-cluster]# ./redis-trib.rb check 127.0.0.1:7005
- >>> Performing Cluster Check (using node 127.0.0.1:7005)
- M: a5db243087d8bd423b9285fa8513eddee9bb59a6 127.0.0.1:7005
- slots:5461-10922 (5462 slots) master
- 0 additional replica(s)
- S: 50ce1ea59106b4c2c6bc502593a6a7a7dabf5041 127.0.0.1:7004
- slots: (0 slots) slave
- replicates dd19221c404fb2fc4da37229de56bab755c76f2b
- M: f9886c71e98a53270f7fda961e1c5f730382d48f 127.0.0.1:7003
- slots:10923-16383 (5461 slots) master
- 1 additional replica(s)
- M: dd19221c404fb2fc4da37229de56bab755c76f2b 127.0.0.1:7001
- slots:0-5460 (5461 slots) master
- 1 additional replica(s)
- S: 8bb3ede48319b46d0015440a91ab277da9353c8b 127.0.0.1:7006
- slots: (0 slots) slave
- replicates f9886c71e98a53270f7fda961e1c5f730382d48f
- [OK] All nodes agree about slots configuration.
- >>> Check for open slots...
- >>> Check slots coverage...
- [OK] All 16384 slots covered.
- [root@localhost redis-cluster]#
可以看到集群连接不了7002节点,而7005有原来的S转换为M节点,代替了原来的7002节点。我们可以获取name值:
- [root@localhost redis01]# ./redis-cli -c -p 7001
- 127.0.0.1:7001> get name
- -> Redirected to slot [5798] located at 127.0.0.1:7005
- "andy"
- 127.0.0.1:7005>
- 127.0.0.1:7005>
从7001节点连入,自动跳转到7005节点,并且获取name值。
现在我们将7002节点恢复,看是否会自动加入集群中以及充当的M还是S节点。
- [root@localhost redis-cluster]# cd redis02
- [root@localhost redis02]# ./redis-server redis.conf
- [root@localhost redis02]#
在check一下7002节点
- [root@localhost redis-cluster]# ./redis-trib.rb check 127.0.0.1:7002
- >>> Performing Cluster Check (using node 127.0.0.1:7002)
- S: 1f07d76585bfab35f91ec711ac53ab4bc00f2d3a 127.0.0.1:7002
- slots: (0 slots) slave
- replicates a5db243087d8bd423b9285fa8513eddee9bb59a6
- M: f9886c71e98a53270f7fda961e1c5f730382d48f 127.0.0.1:7003
- slots:10923-16383 (5461 slots) master
- 1 additional replica(s)
- M: a5db243087d8bd423b9285fa8513eddee9bb59a6 127.0.0.1:7005
- slots:5461-10922 (5462 slots) master
- 1 additional replica(s)
- S: 50ce1ea59106b4c2c6bc502593a6a7a7dabf5041 127.0.0.1:7004
- slots: (0 slots) slave
- replicates dd19221c404fb2fc4da37229de56bab755c76f2b
- S: 8bb3ede48319b46d0015440a91ab277da9353c8b 127.0.0.1:7006
- slots: (0 slots) slave
- replicates f9886c71e98a53270f7fda961e1c5f730382d48f
- M: dd19221c404fb2fc4da37229de56bab755c76f2b 127.0.0.1:7001
- 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.
- [root@localhost redis-cluster]#
可以看到7002节点变成了a5db243087d8bd423b9285fa8513eddee9bb59a6 7005的从节点。
五、集群节点添加
节点新增包括新增主节点、从节点两种情况。以下分别做一下测试:
1、新增主节点
新增一个节点7007作为主节点修改配置文件
- [root@localhost redis-cluster]# cp -r redis01 redis07
- [root@localhost redis-cluster]# cd redis07/
- [root@localhost redis07]# sed -i "s/7001/7007/g" ./redis.conf
启动7007redis服务
- [root@localhost redis07]# ./redis-server redis.conf
- [root@localhost redis07]# netstat -anp | grep 7007
- tcp 0 0 127.0.0.1:17007 0.0.0.0:* LISTEN 13441/./redis-serve
- tcp 0 0 127.0.0.1:7007 0.0.0.0:* LISTEN 13441/./redis-serve
- [root@localhost redis07]#
上面可以看到,7007已经启动,现在加入集群中。添加使用redis-trib.rb的add-node命令
- ./redis-trib.rb add-node 127.0.0.1:7007 127.0.0.1:7002
add-node是加入集群节点,127.0.0.1:7007为要加入的节点,127.0.0.1:7002 表示加入的集群的一个节点,用来辨识是哪个集群,理论上那个集群的节点都可以。
执行以下add-node
- [root@localhost redis-cluster]# ./redis-trib.rb add-node 127.0.0.1:7007 127.0.0.1:7002
- >>> Adding node 127.0.0.1:7007 to cluster 127.0.0.1:7002
- >>> Performing Cluster Check (using node 127.0.0.1:7002)
- S: 1f07d76585bfab35f91ec711ac53ab4bc00f2d3a 127.0.0.1:7002
- slots: (0 slots) slave
- replicates a5db243087d8bd423b9285fa8513eddee9bb59a6
- M: f9886c71e98a53270f7fda961e1c5f730382d48f 127.0.0.1:7003
- slots:10923-16383 (5461 slots) master
- 1 additional replica(s)
- M: a5db243087d8bd423b9285fa8513eddee9bb59a6 127.0.0.1:7005
- slots:5461-10922 (5462 slots) master
- 1 additional replica(s)
- S: 50ce1ea59106b4c2c6bc502593a6a7a7dabf5041 127.0.0.1:7004
- slots: (0 slots) slave
- replicates dd19221c404fb2fc4da37229de56bab755c76f2b
- S: 8bb3ede48319b46d0015440a91ab277da9353c8b 127.0.0.1:7006
- slots: (0 slots) slave
- replicates f9886c71e98a53270f7fda961e1c5f730382d48f
- M: dd19221c404fb2fc4da37229de56bab755c76f2b 127.0.0.1:7001
- 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.
- >>> Send CLUSTER MEET to node 127.0.0.1:7007 to make it join the cluster.
- [OK] New node added correctly.
- [root@localhost redis-cluster]#
可以看到7007加入这个Cluster,并成为一个新的节点。
可以check以下7007节点状态
- [root@localhost redis-cluster]# ./redis-trib.rb check 127.0.0.1:7007
- >>> Performing Cluster Check (using node 127.0.0.1:7007)
- M: ee3efb90e5ac0725f15238a64fc60a18a71205d7 127.0.0.1:7007
- slots: (0 slots) master
- 0 additional replica(s)
- S: 8bb3ede48319b46d0015440a91ab277da9353c8b 127.0.0.1:7006
- slots: (0 slots) slave
- replicates f9886c71e98a53270f7fda961e1c5f730382d48f
- M: dd19221c404fb2fc4da37229de56bab755c76f2b 127.0.0.1:7001
- slots:0-5460 (5461 slots) master
- 1 additional replica(s)
- M: f9886c71e98a53270f7fda961e1c5f730382d48f 127.0.0.1:7003
- slots:10923-16383 (5461 slots) master
- 1 additional replica(s)
- S: 1f07d76585bfab35f91ec711ac53ab4bc00f2d3a 127.0.0.1:7002
- slots: (0 slots) slave
- replicates a5db243087d8bd423b9285fa8513eddee9bb59a6
- M: a5db243087d8bd423b9285fa8513eddee9bb59a6 127.0.0.1:7005
- slots:5461-10922 (5462 slots) master
- 1 additional replica(s)
- S: 50ce1ea59106b4c2c6bc502593a6a7a7dabf5041 127.0.0.1:7004
- slots: (0 slots) slave
- replicates dd19221c404fb2fc4da37229de56bab755c76f2b
- [OK] All nodes agree about slots configuration.
- >>> Check for open slots...
- >>> Check slots coverage...
- [OK] All 16384 slots covered.
- [root@localhost redis-cluster]#
M: ee3efb90e5ac0725f15238a64fc60a18a71205d7 127.0.0.1:7007
slots: (0 slots) master
0 additional replica(s)
上面信息可以看到有4个M节点,3个S节点,7007成为了M主节点,它没有附属的从节点,而且Cluster并未给7007分配哈希卡槽(0 slots)。
可以从客户端连接集群查看一下,集群节点的连接情况
- [root@localhost redis-cluster]# cd redis07/
- [root@localhost redis07]# ./redis-cli -c -p 7007
- 127.0.0.1:7007> cluster nodes
- 8bb3ede48319b46d0015440a91ab277da9353c8b 127.0.0.1:7006 slave f9886c71e98a53270f7fda961e1c5f730382d48f 0 1462955393326 3 connected
- dd19221c404fb2fc4da37229de56bab755c76f2b 127.0.0.1:7001 master - 0 1462955388247 1 connected 0-5460
- ee3efb90e5ac0725f15238a64fc60a18a71205d7 127.0.0.1:7007 myself,master - 0 0 0 connected
- f9886c71e98a53270f7fda961e1c5f730382d48f 127.0.0.1:7003 master - 0 1462955390270 3 connected 10923-16383
- 1f07d76585bfab35f91ec711ac53ab4bc00f2d3a 127.0.0.1:7002 slave a5db243087d8bd423b9285fa8513eddee9bb59a6 0 1462955394334 7 connected
- a5db243087d8bd423b9285fa8513eddee9bb59a6 127.0.0.1:7005 master - 0 1462955392309 7 connected 5461-10922
- 50ce1ea59106b4c2c6bc502593a6a7a7dabf5041 127.0.0.1:7004 slave dd19221c404fb2fc4da37229de56bab755c76f2b 0 1462955389663 1 connected
- 127.0.0.1:7007>
redis-cluster在新增节点时并未分配卡槽,需要我们手动对集群进行重新分片迁移数据,需要重新分片命令 reshard
redis-trib.rb reshard 127.0.0.1:7005
这个命令是用来迁移slot节点的,后面的127.0.0.1:7005是表示是哪个集群,端口填[7000-7007]都可以,执行结果如下:
- [root@localhost redis-cluster]# ./redis-trib.rb reshard 127.0.0.1:7005
- >>> Performing Cluster Check (using node 127.0.0.1:7005)
- M: a5db243087d8bd423b9285fa8513eddee9bb59a6 127.0.0.1:7005
- slots:5461-10922 (5462 slots) master
- 1 additional replica(s)
- S: 50ce1ea59106b4c2c6bc502593a6a7a7dabf5041 127.0.0.1:7004
- slots: (0 slots) slave
- replicates dd19221c404fb2fc4da37229de56bab755c76f2b
- M: f9886c71e98a53270f7fda961e1c5f730382d48f 127.0.0.1:7003
- slots:10923-16383 (5461 slots) master
- 1 additional replica(s)
- S: 1f07d76585bfab35f91ec711ac53ab4bc00f2d3a 127.0.0.1:7002
- slots: (0 slots) slave
- replicates a5db243087d8bd423b9285fa8513eddee9bb59a6
- M: ee3efb90e5ac0725f15238a64fc60a18a71205d7 127.0.0.1:7007
- slots: (0 slots) master
- 0 additional replica(s)
- M: dd19221c404fb2fc4da37229de56bab755c76f2b 127.0.0.1:7001
- slots:0-5460 (5461 slots) master
- 1 additional replica(s)
- S: 8bb3ede48319b46d0015440a91ab277da9353c8b 127.0.0.1:7006
- slots: (0 slots) slave
- replicates f9886c71e98a53270f7fda961e1c5f730382d48f
- [OK] All nodes agree about slots configuration.
- >>> Check for open slots...
- >>> Check slots coverage...
- [OK] All 16384 slots covered.
- How many slots do you want to move (from 1 to 16384)?
它提示我们需要迁移多少slot到7007上,我们平分16384个哈希槽给4个节点:16384/4 = 4096,我们需要移动4096个槽点到7007上。
- [OK] All 16384 slots covered.
- How many slots do you want to move (from 1 to 16384)? 4096
- What is the receiving node ID?
需要输入7007的节点id,ee3efb90e5ac0725f15238a64fc60a18a71205d7
- Please enter all the source node IDs.
- Type 'all' to use all the nodes as source nodes for the hash slots.
- Type 'done' once you entered all the source nodes IDs.
- Source node #1:
redis-trib 会向你询问重新分片的源节点(source node),即,要从特点的哪个节点中取出 4096 个哈希槽,还是从全部节点提取4096个哈希槽, 并将这些槽移动到7007节点上面。
如果我们不打算从特定的节点上取出指定数量的哈希槽,那么可以向redis-trib输入 all,这样的话, 集群中的所有主节点都会成为源节点,redis-trib从各个源节点中各取出一部分哈希槽,凑够4096个,然后移动到7007节点上:
- Source node #1:all
然后开始从别的主节点迁移哈希槽,并且确认。
- Moving slot 1343 from dd19221c404fb2fc4da37229de56bab755c76f2b
- Moving slot 1344 from dd19221c404fb2fc4da37229de56bab755c76f2b
- Moving slot 1345 from dd19221c404fb2fc4da37229de56bab755c76f2b
- Moving slot 1346 from dd19221c404fb2fc4da37229de56bab755c76f2b
- Moving slot 1347 from dd19221c404fb2fc4da37229de56bab755c76f2b
- Moving slot 1348 from dd19221c404fb2fc4da37229de56bab755c76f2b
- Moving slot 1349 from dd19221c404fb2fc4da37229de56bab755c76f2b
- Moving slot 1350 from dd19221c404fb2fc4da37229de56bab755c76f2b
- Moving slot 1351 from dd19221c404fb2fc4da37229de56bab755c76f2b
- Moving slot 1352 from dd19221c404fb2fc4da37229de56bab755c76f2b
- Moving slot 1353 from dd19221c404fb2fc4da37229de56bab755c76f2b
- Moving slot 1354 from dd19221c404fb2fc4da37229de56bab755c76f2b
- Moving slot 1355 from dd19221c404fb2fc4da37229de56bab755c76f2b
- Moving slot 1356 from dd19221c404fb2fc4da37229de56bab755c76f2b
- Moving slot 1357 from dd19221c404fb2fc4da37229de56bab755c76f2b
- Moving slot 1358 from dd19221c404fb2fc4da37229de56bab755c76f2b
- Moving slot 1359 from dd19221c404fb2fc4da37229de56bab755c76f2b
- Moving slot 1360 from dd19221c404fb2fc4da37229de56bab755c76f2b
- Moving slot 1361 from dd19221c404fb2fc4da37229de56bab755c76f2b
- Moving slot 1362 from dd19221c404fb2fc4da37229de56bab755c76f2b
- Moving slot 1363 from dd19221c404fb2fc4da37229de56bab755c76f2b
- Moving slot 1364 from dd19221c404fb2fc4da37229de56bab755c76f2b
- Do you want to proceed with the proposed reshard plan (yes/no)? yes
确认之后,redis-trib就开始执行分片操作,将哈希槽一个一个从源主节点移动到7007目标主节点。
重新分片结束后我们可以check以下节点的分配情况。
- [root@localhost redis-cluster]# ./redis-trib.rb check 127.0.0.1:7001
- >>> Performing Cluster Check (using node 127.0.0.1:7001)
- M: dd19221c404fb2fc4da37229de56bab755c76f2b 127.0.0.1:7001
- slots:1365-5460 (4096 slots) master
- 1 additional replica(s)
- M: ee3efb90e5ac0725f15238a64fc60a18a71205d7 127.0.0.1:7007
- slots:0-1364,5461-6826,10923-12287 (4096 slots) master
- 0 additional replica(s)
- M: a5db243087d8bd423b9285fa8513eddee9bb59a6 127.0.0.1:7005
- slots:6827-10922 (4096 slots) master
- 1 additional replica(s)
- S: 8bb3ede48319b46d0015440a91ab277da9353c8b 127.0.0.1:7006
- slots: (0 slots) slave
- replicates f9886c71e98a53270f7fda961e1c5f730382d48f
- M: f9886c71e98a53270f7fda961e1c5f730382d48f 127.0.0.1:7003
- slots:12288-16383 (4096 slots) master
- 1 additional replica(s)
- S: 1f07d76585bfab35f91ec711ac53ab4bc00f2d3a 127.0.0.1:7002
- slots: (0 slots) slave
- replicates a5db243087d8bd423b9285fa8513eddee9bb59a6
- S: 50ce1ea59106b4c2c6bc502593a6a7a7dabf5041 127.0.0.1:7004
- slots: (0 slots) slave
- replicates dd19221c404fb2fc4da37229de56bab755c76f2b
- [OK] All nodes agree about slots configuration.
- >>> Check for open slots...
- >>> Check slots coverage...
- [OK] All 16384 slots covered.
- [root@localhost redis-cluster]#
slots:0-1364,5461-6826,10923-12287 (4096 slots) master
可以看到7007节点分片的哈希槽片不是连续的,间隔的移动。
- [root@localhost redis-cluster]# cd redis07/
- [root@localhost redis07]# ./redis-cli -c 7007
- Could not connect to Redis at 127.0.0.1:6379: Connection refused
- [root@localhost redis07]# ./redis-cli -c -p 7007
- 127.0.0.1:7007> keys *
- 1) "name"
- 2) "age"
- 127.0.0.1:7007>
- 127.0.0.1:7007>
可以看到将7001的age[741]和name[5798]移动到7007节点上,
主节点7007添加成功。
2、新增从节点
新增一个节点7008节点,使用add-node --slave命令。
- [root@localhost redis-cluster]# cp -r redis01/ redis08
- [root@localhost redis-cluster]# cd redis08/
- [root@localhost redis08]# sed -i "s/7001/7008/g" ./redis.conf
- [root@localhost redis08]# ./redis-server redis.conf
redis-trib增加从节点的命令为:
- ./redis-trib.rb add-node --slave --master-id $[nodeid] 127.0.0.1:7008 127.0.0.1:7000
nodeid为要加到master主节点的node id,127.0.0.1:7008为新增的从节点,127.0.0.1:7000为集群的一个节点(集群的任意节点都行),用来辨识是哪个集群;如果没有给定那个主节点--master-id的话,redis-trib将会将新增的从节点随机到从节点较少的主节点上。
现在我们添加一下7008,看是否会自动加到没有从节点的7007主节点上。
- [root@localhost redis-cluster]# ./redis-trib.rb add-node --slave 127.0.0.1:7008 127.0.0.1:7001>>> Adding node 127.0.0.1:7008 to cluster 127.0.0.1:7001
- >>> Performing Cluster Check (using node 127.0.0.1:7001)
- M: dd19221c404fb2fc4da37229de56bab755c76f2b 127.0.0.1:7001
- slots:1365-5460 (4096 slots) master
- 1 additional replica(s)
- M: ee3efb90e5ac0725f15238a64fc60a18a71205d7 127.0.0.1:7007
- slots:0-1364,5461-6826,10923-12287 (4096 slots) master
- 0 additional replica(s)
- M: a5db243087d8bd423b9285fa8513eddee9bb59a6 127.0.0.1:7005
- slots:6827-10922 (4096 slots) master
- 1 additional replica(s)
- S: 8bb3ede48319b46d0015440a91ab277da9353c8b 127.0.0.1:7006
- slots: (0 slots) slave
- replicates f9886c71e98a53270f7fda961e1c5f730382d48f
- M: f9886c71e98a53270f7fda961e1c5f730382d48f 127.0.0.1:7003
- slots:12288-16383 (4096 slots) master
- 1 additional replica(s)
- S: 1f07d76585bfab35f91ec711ac53ab4bc00f2d3a 127.0.0.1:7002
- slots: (0 slots) slave
- replicates a5db243087d8bd423b9285fa8513eddee9bb59a6
- S: 50ce1ea59106b4c2c6bc502593a6a7a7dabf5041 127.0.0.1:7004
- slots: (0 slots) slave
- replicates dd19221c404fb2fc4da37229de56bab755c76f2b
- [OK] All nodes agree about slots configuration.
- >>> Check for open slots...
- >>> Check slots coverage...
- [OK] All 16384 slots covered.
- Automatically selected master 127.0.0.1:7007
- >>> Send CLUSTER MEET to node 127.0.0.1:7008 to make it join the cluster.
- Waiting for the cluster to join.
- >>> Configure node as replica of 127.0.0.1:7007.
- [OK] New node added correctly.
- [root@localhost redis-cluster]#
可以看到自动选择了127.0.0.1:7007为master主节点,并且添加成功。
可以check一下7008:
- [root@localhost redis-cluster]# ./redis-trib.rb check 127.0.0.1:7008
- >>> Performing Cluster Check (using node 127.0.0.1:7008)
- S: 2ab1b061c36f30ae35604e9a171ae3afdc3c87e5 127.0.0.1:7008
- slots: (0 slots) slave
- replicates ee3efb90e5ac0725f15238a64fc60a18a71205d7
- M: a5db243087d8bd423b9285fa8513eddee9bb59a6 127.0.0.1:7005
- slots:6827-10922 (4096 slots) master
- 1 additional replica(s)
- M: dd19221c404fb2fc4da37229de56bab755c76f2b 127.0.0.1:7001
- slots:1365-5460 (4096 slots) master
- 1 additional replica(s)
- S: 8bb3ede48319b46d0015440a91ab277da9353c8b 127.0.0.1:7006
- slots: (0 slots) slave
- replicates f9886c71e98a53270f7fda961e1c5f730382d48f
- M: ee3efb90e5ac0725f15238a64fc60a18a71205d7 127.0.0.1:7007
- slots:0-1364,5461-6826,10923-12287 (4096 slots) master
- 1 additional replica(s)
- S: 50ce1ea59106b4c2c6bc502593a6a7a7dabf5041 127.0.0.1:7004
- slots: (0 slots) slave
- replicates dd19221c404fb2fc4da37229de56bab755c76f2b
- M: f9886c71e98a53270f7fda961e1c5f730382d48f 127.0.0.1:7003
- slots:12288-16383 (4096 slots) master
- 1 additional replica(s)
- S: 1f07d76585bfab35f91ec711ac53ab4bc00f2d3a 127.0.0.1:7002
- slots: (0 slots) slave
- replicates a5db243087d8bd423b9285fa8513eddee9bb59a6
- [OK] All nodes agree about slots configuration.
- >>> Check for open slots...
- >>> Check slots coverage...
- [OK] All 16384 slots covered.
- [root@localhost redis-cluster]#
可以看到7008作为了7007的从节点。
再测试一下指定主节点添加从节点,给7007增加7009从节点。
- [root@localhost redis-cluster]# cp -r redis01/ redis09
- [root@localhost redis-cluster]# cd redis09
- [root@localhost redis09]# sed -i "s/7001/7009/g" ./redis.conf
- [root@localhost redis09]# ./redis-server redis.conf
添加7007主节点上
- [root@localhost redis-cluster]# ./redis-trib.rb add-node --slave --master-id ee3efb90e5ac0725f15238a64fc60a18a71205d7 127.0.0.1:7009 127.0.0.1:7001
- >>> Adding node 127.0.0.1:7009 to cluster 127.0.0.1:7001
- >>> Performing Cluster Check (using node 127.0.0.1:7001)
- M: dd19221c404fb2fc4da37229de56bab755c76f2b 127.0.0.1:7001
- slots:1365-5460 (4096 slots) master
- 1 additional replica(s)
- S: 2ab1b061c36f30ae35604e9a171ae3afdc3c87e5 127.0.0.1:7008
- slots: (0 slots) slave
- replicates ee3efb90e5ac0725f15238a64fc60a18a71205d7
- M: ee3efb90e5ac0725f15238a64fc60a18a71205d7 127.0.0.1:7007
- slots:0-1364,5461-6826,10923-12287 (4096 slots) master
- 1 additional replica(s)
- M: a5db243087d8bd423b9285fa8513eddee9bb59a6 127.0.0.1:7005
- slots:6827-10922 (4096 slots) master
- 1 additional replica(s)
- S: 8bb3ede48319b46d0015440a91ab277da9353c8b 127.0.0.1:7006
- slots: (0 slots) slave
- replicates f9886c71e98a53270f7fda961e1c5f730382d48f
- M: f9886c71e98a53270f7fda961e1c5f730382d48f 127.0.0.1:7003
- slots:12288-16383 (4096 slots) master
- 1 additional replica(s)
- S: 1f07d76585bfab35f91ec711ac53ab4bc00f2d3a 127.0.0.1:7002
- slots: (0 slots) slave
- replicates a5db243087d8bd423b9285fa8513eddee9bb59a6
- S: 50ce1ea59106b4c2c6bc502593a6a7a7dabf5041 127.0.0.1:7004
- slots: (0 slots) slave
- replicates dd19221c404fb2fc4da37229de56bab755c76f2b
- [OK] All nodes agree about slots configuration.
- >>> Check for open slots...
- >>> Check slots coverage...
- [OK] All 16384 slots covered.
- >>> Send CLUSTER MEET to node 127.0.0.1:7009 to make it join the cluster.
- Waiting for the cluster to join.
- >>> Configure node as replica of 127.0.0.1:7007.
- [OK] New node added correctly.
- [root@localhost redis-cluster]#
显示从节点7009节点添加到7007主节点,可以看一下7007的从节点,如下:
- [root@localhost redis-cluster]# cd ./redis07
- [root@localhost redis07]# ./redis-cli -c -p 7007 cluster nodes | grep ee3efb90e5ac0725f15238a64fc60a18a71205d7
- 1f51443ede952b98724fea2a12f61fe710ab6cb1 127.0.0.1:7009 slave ee3efb90e5ac0725f15238a64fc60a18a71205d7 0 1462962710266 8 connected
- ee3efb90e5ac0725f15238a64fc60a18a71205d7 127.0.0.1:7007 myself,master - 0 0 8 connected 0-1364 5461-6826 10923-12287
- 2ab1b061c36f30ae35604e9a171ae3afdc3c87e5 127.0.0.1:7008 slave ee3efb90e5ac0725f15238a64fc60a18a71205d7 0 1462962711607 8 connected
- [root@localhost redis07]#
maser 7007有2个slave 7008,7009。
我们测试一下7007节点挂掉,看7008和7009那个成为主节点。
- [root@localhost redis-cluster]# ps -ef | grep redis
- root 7950 1 0 12:50 ? 00:02:05 ./redis-server 127.0.0.1:7001 [cluster]
- root 7956 1 0 12:50 ? 00:02:11 ./redis-server 127.0.0.1:7003 [cluster]
- root 7960 1 0 12:50 ? 00:01:47 ./redis-server 127.0.0.1:7004 [cluster]
- root 7964 1 0 12:50 ? 00:02:07 ./redis-server 127.0.0.1:7005 [cluster]
- root 7966 1 0 12:50 ? 00:01:46 ./redis-server 127.0.0.1:7006 [cluster]
- root 12070 1 0 15:14 ? 00:01:08 ./redis-server 127.0.0.1:7002 [cluster]
- root 13441 1 0 16:09 ? 00:01:25 ./redis-server 127.0.0.1:7007 [cluster]
- root 15939 1 0 17:41 ? 00:00:20 ./redis-server 127.0.0.1:7008 [cluster]
- root 16623 1 0 18:07 ? 00:00:10 ./redis-server 127.0.0.1:7009 [cluster]
- root 17295 10581 0 18:37 pts/2 00:00:00 grep --color=auto redis
- [root@localhost redis-cluster]# kill -9 13441
- [root@localhost redis-cluster]# cd ./redis08
- [root@localhost redis08]# ./redis-cli -c -p 7008
- 127.0.0.1:7008> get name
- -> Redirected to slot [5798] located at 127.0.0.1:7009
- "andy"
- 127.0.0.1:7009> cluster nodes
- ee3efb90e5ac0725f15238a64fc60a18a71205d7 127.0.0.1:7007 master,fail - 1462963082317 1462963080194 8 disconnected
- 50ce1ea59106b4c2c6bc502593a6a7a7dabf5041 127.0.0.1:7004 slave dd19221c404fb2fc4da37229de56bab755c76f2b 0 1462963170968 1 connected
- f9886c71e98a53270f7fda961e1c5f730382d48f 127.0.0.1:7003 master - 0 1462963168525 3 connected 12288-16383
- dd19221c404fb2fc4da37229de56bab755c76f2b 127.0.0.1:7001 master - 0 1462963164466 1 connected 1365-5460
- 2ab1b061c36f30ae35604e9a171ae3afdc3c87e5 127.0.0.1:7008 slave 1f51443ede952b98724fea2a12f61fe710ab6cb1 0 1462963167508 9 connected
- 1f51443ede952b98724fea2a12f61fe710ab6cb1 127.0.0.1:7009 myself,master - 0 0 9 connected 0-1364 5461-6826 10923-12287
- 1f07d76585bfab35f91ec711ac53ab4bc00f2d3a 127.0.0.1:7002 slave a5db243087d8bd423b9285fa8513eddee9bb59a6 0 1462963170564 7 connected
- 8bb3ede48319b46d0015440a91ab277da9353c8b 127.0.0.1:7006 slave f9886c71e98a53270f7fda961e1c5f730382d48f 0 1462963167915 3 connected
- a5db243087d8bd423b9285fa8513eddee9bb59a6 127.0.0.1:7005 master - 0 1462963169538 7 connected 6827-10922
- 127.0.0.1:7009>
可以看到7009代替7007成了主节点。
重启7007之后,会自动变成7009的从节点。
- [root@localhost redis-cluster]# cd redis07
- [root@localhost redis07]# ./redis-server redis.conf
- [root@localhost redis07]# cd ../
- [root@localhost redis-cluster]# ./redis-trib.rb check 127.0.0.1:7007
- >>> Performing Cluster Check (using node 127.0.0.1:7007)
- S: ee3efb90e5ac0725f15238a64fc60a18a71205d7 127.0.0.1:7007
- slots: (0 slots) slave
- replicates 1f51443ede952b98724fea2a12f61fe710ab6cb1
- S: 50ce1ea59106b4c2c6bc502593a6a7a7dabf5041 127.0.0.1:7004
- slots: (0 slots) slave
- replicates dd19221c404fb2fc4da37229de56bab755c76f2b
- M: 1f51443ede952b98724fea2a12f61fe710ab6cb1 127.0.0.1:7009
- slots:0-1364,5461-6826,10923-12287 (4096 slots) master
- 2 additional replica(s)
- S: 8bb3ede48319b46d0015440a91ab277da9353c8b 127.0.0.1:7006
- slots: (0 slots) slave
- replicates f9886c71e98a53270f7fda961e1c5f730382d48f
- M: dd19221c404fb2fc4da37229de56bab755c76f2b 127.0.0.1:7001
- slots:1365-5460 (4096 slots) master
- 1 additional replica(s)
- M: a5db243087d8bd423b9285fa8513eddee9bb59a6 127.0.0.1:7005
- slots:6827-10922 (4096 slots) master
- 1 additional replica(s)
- S: 1f07d76585bfab35f91ec711ac53ab4bc00f2d3a 127.0.0.1:7002
- slots: (0 slots) slave
- replicates a5db243087d8bd423b9285fa8513eddee9bb59a6
- M: f9886c71e98a53270f7fda961e1c5f730382d48f 127.0.0.1:7003
- slots:12288-16383 (4096 slots) master
- 1 additional replica(s)
- S: 2ab1b061c36f30ae35604e9a171ae3afdc3c87e5 127.0.0.1:7008
- slots: (0 slots) slave
- replicates 1f51443ede952b98724fea2a12f61fe710ab6cb1
- [OK] All nodes agree about slots configuration.
- >>> Check for open slots...
- >>> Check slots coverage...
- [OK] All 16384 slots covered.
- [root@localhost redis-cluster]#
验证了之前的测试。
六、节点的移除
和节点添加一样,移除节点也有移除主节点,从节点。
1、移除主节点
移除节点使用redis-trib的del-node命令,
- redis-trib del-node 127.0.0.1:7002 ${node-id}
127.0.0.1:7002位集群节点,node-id为要删除的主节点。 和添加节点不同,移除节点node-id是必需的,测试删除7001主节点:
- [root@localhost redis-cluster]# ./redis-trib.rb del-node 127.0.0.1:7001 <span style="font-size: 14px;">dd19221c404fb2fc4da37229de56bab755c76f2b</span>
- >>> Removing node <span style="font-size: 14px;">dd19221c404fb2fc4da37229de56bab755c76f2b</span> from cluster 127.0.0.1:7002
- [ERR] Node 127.0.0.1:7001 is not empty! Reshard data away and try again.
- [root@localhost redis-cluster]#
redis cluster提示7001已经有数据了,不能够被删除,需要将他的数据转移出去,也就是和新增主节点一样需重新分片。
- [root@localhost redis-cluster]# ./redis-trib.rb reshard 127.0.0.1:7002
执行以后会提示我们移除的大小,因为7001占用了4096个槽点
- >>> Check for open slots...
- >>> Check slots coverage...
- [OK] All 16384 slots covered.
- How many slots do you want to move (from 1 to 16384)?
输入4096
提示移动的node id,填写7009的node id。
- How many slots do you want to move (from 1 to 16384)? 4096
- What is the receiving node ID?
需要移动到全部主节点上还是单个主节点
- Please enter all the source node IDs.
- Type 'all' to use all the nodes as source nodes for the hash slots.
- Type 'done' once you entered all the source nodes IDs.
- Source node #1:
将4096个槽点移动到7009上,填写7001的node id :dd19221c404fb2fc4da37229de56bab755c76f2b
- Source node #1:dd19221c404fb2fc4da37229de56bab755c76f2b
- Source node #2:done
- Do you want to proceed with the proposed reshard plan (yes/no)? yes
确认之后会一个一个将7001的卡槽移到到7009上。
- [root@localhost redis-cluster]# ./redis-trib.rb check 127.0.0.1:7009
- >>> Performing Cluster Check (using node 127.0.0.1:7009)
- M: 1f51443ede952b98724fea2a12f61fe710ab6cb1 127.0.0.1:7009
- slots:0-6826,10923-12287 (8192 slots) master
- 3 additional replica(s)
- S: ee3efb90e5ac0725f15238a64fc60a18a71205d7 127.0.0.1:7007
- slots: (0 slots) slave
- replicates 1f51443ede952b98724fea2a12f61fe710ab6cb1
- S: 50ce1ea59106b4c2c6bc502593a6a7a7dabf5041 127.0.0.1:7004
- slots: (0 slots) slave
- replicates 1f51443ede952b98724fea2a12f61fe710ab6cb1
- M: f9886c71e98a53270f7fda961e1c5f730382d48f 127.0.0.1:7003
- slots:12288-16383 (4096 slots) master
- 1 additional replica(s)
- M: dd19221c404fb2fc4da37229de56bab755c76f2b 127.0.0.1:7001
- slots: (0 slots) master
- 0 additional replica(s)
- S: 2ab1b061c36f30ae35604e9a171ae3afdc3c87e5 127.0.0.1:7008
- slots: (0 slots) slave
- replicates 1f51443ede952b98724fea2a12f61fe710ab6cb1
- S: 1f07d76585bfab35f91ec711ac53ab4bc00f2d3a 127.0.0.1:7002
- slots: (0 slots) slave
- replicates a5db243087d8bd423b9285fa8513eddee9bb59a6
- S: 8bb3ede48319b46d0015440a91ab277da9353c8b 127.0.0.1:7006
- slots: (0 slots) slave
- replicates f9886c71e98a53270f7fda961e1c5f730382d48f
- M: a5db243087d8bd423b9285fa8513eddee9bb59a6 127.0.0.1:7005
- slots:6827-10922 (4096 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.
- [root@localhost redis-cluster]#
可以看到7001有0个卡槽,而7009有8192个卡槽。
在执行移除操作
- [root@localhost redis-cluster]# ./redis-trib.rb del-node 127.0.0.1:7002 dd19221c404fb2fc4da37229de56bab755c76f2b
- >>> Removing node dd19221c404fb2fc4da37229de56bab755c76f2b from cluster 127.0.0.1:7002
- >>> Sending CLUSTER FORGET messages to the cluster...
- >>> SHUTDOWN the node.
- [root@localhost redis-cluster]#
已经删除了7001节点。
- [root@localhost redis-cluster]# ./redis-trib.rb check 127.0.0.1:7001
- [ERR] Sorry, can't connect to node 127.0.0.1:7001
- [root@localhost redis-cluster]# ./redis-trib.rb check 127.0.0.1:7009
- >>> Performing Cluster Check (using node 127.0.0.1:7009)
- M: 1f51443ede952b98724fea2a12f61fe710ab6cb1 127.0.0.1:7009
- slots:0-6826,10923-12287 (8192 slots) master
- 3 additional replica(s)
- S: ee3efb90e5ac0725f15238a64fc60a18a71205d7 127.0.0.1:7007
- slots: (0 slots) slave
- replicates 1f51443ede952b98724fea2a12f61fe710ab6cb1
- S: 50ce1ea59106b4c2c6bc502593a6a7a7dabf5041 127.0.0.1:7004
- slots: (0 slots) slave
- replicates 1f51443ede952b98724fea2a12f61fe710ab6cb1
- M: f9886c71e98a53270f7fda961e1c5f730382d48f 127.0.0.1:7003
- slots:12288-16383 (4096 slots) master
- 1 additional replica(s)
- S: 2ab1b061c36f30ae35604e9a171ae3afdc3c87e5 127.0.0.1:7008
- slots: (0 slots) slave
- replicates 1f51443ede952b98724fea2a12f61fe710ab6cb1
- S: 1f07d76585bfab35f91ec711ac53ab4bc00f2d3a 127.0.0.1:7002
- slots: (0 slots) slave
- replicates a5db243087d8bd423b9285fa8513eddee9bb59a6
- S: 8bb3ede48319b46d0015440a91ab277da9353c8b 127.0.0.1:7006
- slots: (0 slots) slave
- replicates f9886c71e98a53270f7fda961e1c5f730382d48f
- M: a5db243087d8bd423b9285fa8513eddee9bb59a6 127.0.0.1:7005
- slots:6827-10922 (4096 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.
- [root@localhost redis-cluster]#
可以看到7001已经连接不了;而7001的从节点7004自动分配到了7009主节点中,7009现在3个从节点。
2、移除从节点
比如删除7009的7008节点:
- [root@localhost redis-cluster]# ./redis-trib.rb del-node 127.0.0.1:7009 2ab1b061c36f30ae35604e9a171ae3afdc3c87e5
- >>> Removing node 2ab1b061c36f30ae35604e9a171ae3afdc3c87e5 from cluster 127.0.0.1:7009
- >>> Sending CLUSTER FORGET messages to the cluster...
- >>> SHUTDOWN the node.
- [root@localhost redis-cluster]# ./redis-trib.rb check 127.0.0.1:7008
- [ERR] Sorry, can't connect to node 127.0.0.1:7008
- [root@localhost redis-cluster]#
删除从节点比较方便,现在redis-cluster中有3个主节点,4个从节点,如下:
- [root@localhost redis-cluster]# ./redis-trib.rb check 127.0.0.1:7009
- >>> Performing Cluster Check (using node 127.0.0.1:7009)
- M: 1f51443ede952b98724fea2a12f61fe710ab6cb1 127.0.0.1:7009
- slots:0-6826,10923-12287 (8192 slots) master
- 2 additional replica(s)
- S: ee3efb90e5ac0725f15238a64fc60a18a71205d7 127.0.0.1:7007
- slots: (0 slots) slave
- replicates 1f51443ede952b98724fea2a12f61fe710ab6cb1
- S: 50ce1ea59106b4c2c6bc502593a6a7a7dabf5041 127.0.0.1:7004
- slots: (0 slots) slave
- replicates 1f51443ede952b98724fea2a12f61fe710ab6cb1
- M: f9886c71e98a53270f7fda961e1c5f730382d48f 127.0.0.1:7003
- slots:12288-16383 (4096 slots) master
- 1 additional replica(s)
- S: 1f07d76585bfab35f91ec711ac53ab4bc00f2d3a 127.0.0.1:7002
- slots: (0 slots) slave
- replicates a5db243087d8bd423b9285fa8513eddee9bb59a6
- S: 8bb3ede48319b46d0015440a91ab277da9353c8b 127.0.0.1:7006
- slots: (0 slots) slave
- replicates f9886c71e98a53270f7fda961e1c5f730382d48f
- M: a5db243087d8bd423b9285fa8513eddee9bb59a6 127.0.0.1:7005
- slots:6827-10922 (4096 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.
- [root@localhost redis-cluster]#
ok,测试到这儿吧。