Cluster

版权声明 本站原创文章 由 萌叔 发表 转载请注明 萌叔 | http://vearne.cc 1.前言 在前面的文章中， 《REDIS-CLUSTER集群创建内部细节详解》 萌叔创建一个Redis集群。 这篇文章，我会为集群添加2个节点，并介绍slot的迁移过程。 2.集群扩容 添加主节点127.0.0.1:7006 redis-cli --cluster add-node 127.0.0.1:7006 127.0.0.1:7000 添加从节点127.0.0.1:7007(并指定其Master节点） redis-cli --cluster add-node 127.0.0.1:7007 127.0.0.1:7000 --cluster-slave --cluster-master-id 86f3cb72813a2d07711b56b3143ff727911f4e1e 新添加的节点上并没有slot分布，需要通过命令让slot重新分布 root@BJ-02:~/cluster-test/7007# redis-cli --cluster reshard 127.0.0.1:7000 >>> Performing Cluster Check (using node 127.0.0.1:7000) S: 7eb7ceb4d886580c6d122e7fd92e436594cc105e 127.0.0.1:7000 slots: (0 slots) slave replicates be905740b96469fc6f20339fc9898e153c06d497 M: 86f3cb72813a2d07711b56b3143ff727911f4e1e 127.0.0.1:7006 slots: (0 slots) master 1 additional replica(s) M: be905740b96469fc6f20339fc9898e153c06d497 127.0.0.1:7005 slots:[0-5460] (5461 slots) master 1 additional replica(s) S: 9e29dd4b2a7318e0e29a48ae4b37a7bd5ea0a828 127.0.0.1:7007 slots: (0 slots) slave replicates 86f3cb72813a2d07711b56b3143ff727911f4e1e S: 603a8a403536f625f53467881f5f78def9bd46e5 127.0.0.1:7003 slots: (0 slots) slave replicates 784fa4b720213b0e2b51a4542469f5e318e8658b M: 4e0e4be1b4afd2cd1d10166a6788449dd812a4c0 127.0.0.1:7002 slots:[10923-16383] (5461 slots) master 1 additional replica(s) S: 585c7df69fb267941a40611bbd8ed90349b49175 127.0.0.1:7004 slots: (0 slots) slave replicates 4e0e4be1b4afd2cd1d10166a6788449dd812a4c0 M: 784fa4b720213b0e2b51a4542469f5e318e8658b 127.0.0.1:7001 slots:[5461-10922] (5462 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. How many slots do you want to move (from 1 to 16384)? 0 How many slots do you want to move (from 1 to 16384)? 1 What is the receiving node ID? 86f3cb72813a2d07711b56b3143ff727911f4e1e 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: all Ready to move 1 slots. Source nodes: M: be905740b96469fc6f20339fc9898e153c06d497 127.0.0.1:7005 slots:[0-5460] (5461 slots) master 1 additional replica(s) M: 4e0e4be1b4afd2cd1d10166a6788449dd812a4c0 127.0.0.1:7002 slots:[10923-16383] (5461 slots) master 1 additional replica(s) M: 784fa4b720213b0e2b51a4542469f5e318e8658b 127.0.0.1:7001 slots:[5461-10922] (5462 slots) master 1 additional replica(s) Destination node: M: 86f3cb72813a2d07711b56b3143ff727911f4e1e 127.0.0.1:7006 slots: (0 slots) master 1 additional replica(s) Resharding plan: Moving slot 5461 from 784fa4b720213b0e2b51a4542469f5e318e8658b Do you want to proceed with the proposed reshard plan (yes/no)? yes Moving slot 5461 from 127.0.0.1:7001 to 127.0.0.1:7006: 3. Slot迁移过程 迁移过程在clusterManagerMoveSlot() 中 ...

版权声明 本站原创文章 由 萌叔 发表 转载请注明 萌叔 | http://vearne.cc 本文基于redis 6.2.7 1.引言 Redis-Cluster集群的搭建非常简单。搭建过程见参考资料1。 执行 redis-cli --cluster create 127.0.0.1:7000 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 \ --cluster-replicas 1 root@BJ-02:~/cluster-test# redis-cli --cluster create 127.0.0.1:7000 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 \ > --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 127.0.0.1:7004 to 127.0.0.1:7000 Adding replica 127.0.0.1:7005 to 127.0.0.1:7001 Adding replica 127.0.0.1:7003 to 127.0.0.1:7002 >>> Trying to optimize slaves allocation for anti-affinity [WARNING] Some slaves are in the same host as their master M: 7eb7ceb4d886580c6d122e7fd92e436594cc105e 127.0.0.1:7000 slots:[0-5460] (5461 slots) master M: 784fa4b720213b0e2b51a4542469f5e318e8658b 127.0.0.1:7001 slots:[5461-10922] (5462 slots) master M: 4e0e4be1b4afd2cd1d10166a6788449dd812a4c0 127.0.0.1:7002 slots:[10923-16383] (5461 slots) master S: 603a8a403536f625f53467881f5f78def9bd46e5 127.0.0.1:7003 replicates 784fa4b720213b0e2b51a4542469f5e318e8658b S: 585c7df69fb267941a40611bbd8ed90349b49175 127.0.0.1:7004 replicates 4e0e4be1b4afd2cd1d10166a6788449dd812a4c0 S: be905740b96469fc6f20339fc9898e153c06d497 127.0.0.1:7005 replicates 7eb7ceb4d886580c6d122e7fd92e436594cc105e 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 127.0.0.1:7000) M: 7eb7ceb4d886580c6d122e7fd92e436594cc105e 127.0.0.1:7000 slots:[0-5460] (5461 slots) master 1 additional replica(s) M: 784fa4b720213b0e2b51a4542469f5e318e8658b 127.0.0.1:7001 slots:[5461-10922] (5462 slots) master 1 additional replica(s) M: 4e0e4be1b4afd2cd1d10166a6788449dd812a4c0 127.0.0.1:7002 slots:[10923-16383] (5461 slots) master 1 additional replica(s) S: 585c7df69fb267941a40611bbd8ed90349b49175 127.0.0.1:7004 slots: (0 slots) slave replicates 4e0e4be1b4afd2cd1d10166a6788449dd812a4c0 S: be905740b96469fc6f20339fc9898e153c06d497 127.0.0.1:7005 slots: (0 slots) slave replicates 7eb7ceb4d886580c6d122e7fd92e436594cc105e S: 603a8a403536f625f53467881f5f78def9bd46e5 127.0.0.1:7003 slots: (0 slots) slave replicates 784fa4b720213b0e2b51a4542469f5e318e8658b [OK] All nodes agree about slots configuration. >>> Check for open slots... >>> Check slots coverage... [OK] All 16384 slots covered. 验证 root@BJ-02:~# redis-cli -h 127.0.0.1 -p 7000 127.0.0.1:7000> cluster nodes 784fa4b720213b0e2b51a4542469f5e318e8658b 127.0.0.1:7001@17001 master - 0 1652672999293 2 connected 5461-10922 7eb7ceb4d886580c6d122e7fd92e436594cc105e 127.0.0.1:7000@17000 myself,master - 0 1652672998000 1 connected 0-5460 4e0e4be1b4afd2cd1d10166a6788449dd812a4c0 127.0.0.1:7002@17002 master - 0 1652673000333 3 connected 10923-16383 585c7df69fb267941a40611bbd8ed90349b49175 127.0.0.1:7004@17004 slave 4e0e4be1b4afd2cd1d10166a6788449dd812a4c0 0 1652673000126 3 connected be905740b96469fc6f20339fc9898e153c06d497 127.0.0.1:7005@17005 slave 7eb7ceb4d886580c6d122e7fd92e436594cc105e 0 1652673001373 1 connected 603a8a403536f625f53467881f5f78def9bd46e5 127.0.0.1:7003@17003 slave 784fa4b720213b0e2b51a4542469f5e318e8658b 0 1652673000000 2 connected 一行命令就完成了集群的部署，redis-cli --cluster create到底做了什么。这篇文章萌叔将带你探寻其中的秘密。 ...

版权声明 本站原创文章 由 萌叔 发表 转载请注明 萌叔 | http://vearne.cc 1. 前言 说到Golang的Redis库，用到最多的恐怕是 redigo 和 go-redis。其中 redigo 不支持对集群的访问。 本文想聊聊go-redis 2个高级用法 2. 开启对Cluster中Slave Node的访问 在一个负载比较高的Redis Cluster中，如果允许对slave节点进行读操作将极大的提高集群的吞吐能力。 开启对Slave 节点的访问，受以下3个参数的影响 type ClusterOptions struct { // Enables read-only commands on slave nodes. ReadOnly bool // Allows routing read-only commands to the closest master or slave node. // It automatically enables ReadOnly. RouteByLatency bool // Allows routing read-only commands to the random master or slave node. // It automatically enables ReadOnly. RouteRandomly bool ... } go-redis 选择节点的逻辑如下 ...

版权声明 本站原创文章 由 萌叔 发表 转载请注明 萌叔 | http://vearne.cc 注意 本文参考的ES 5.0.1的源码 1. 查看集群状态 可以通过API查看集群状态 GET /_cluster/state 大致可以得到如下内容 version 集群状态数字版本号 每次更新version + 1 集群重启version不会置0(只会单调增) state_uuid 是集群状态字符串版本号(UUID) master_node master节点 nodes 该版本中的所有节点信息 routing_table 和 routing_nodes 都是描述不同index上的shard在node上的分布关系 2. 集群状态的维护 ES源码中集群状态的对应类为ClusterState.java The cluster state can be updated only on the master node. All updates are performed by on a single thread and controlled by the {@link ClusterService}. After every update the {@link Discovery#publish} method publishes new version of the cluster state to all other nodes in the cluster. In the Zen Discovery it is handled in the {@link PublishClusterStateAction#publish} method ...