The creation and use of redis Cluster

Cluster configuration parameters:

cluster-enabled yes //Enable cluster

cluster-config-file nodes.conf //File that holds cluster information

cluster-node-timeout 5000 //Cluster node timeout

Cluster environment preparation:

Cluster management tool redis-trib is developed by ruby language, you need to install ruby dependencies and environment first;

redis source code file has a management tool, is written with ruby, so you need to install ruby-related software;

yum install ruby rubygems -y

gem install redis

Note: Please refer to this website--> http://gems.ruby-china.org/

$ gem update --system #here ××× please

$ gem -v

2.6.3

$ gem sources --add https://gems.ruby-china.org/ --remove https://rubygems.org/

$ gem sources -l

https://gems.ruby-china.org

#Make sure only gems.ruby-china.org

Note: If you encounter problems with SSL Certificates and you cannot solve them, please use http://gems.ruby-china.org to avoid SSL problems

$ gem sources --add http://gems.ruby-china.org/--remove https://rubygems.org/

Create clusters with redis-trib:

cp /usr/local/src/redis-3.2.0/src/redis-trib.rb /usr/local/bin/redis-trib

Note: redis-trib.rb is a cluster management tool written in ruby.

Note: If it is a binary installation and there is no redis-trib file, you need to download the source file and copy the redis-trib in the source file.

Create a cluster:

Note: Minimum of 3 nodes in cluster

redis-trib 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

Note: After creation, the first 3 are dominant, and the last 3 are subordinate.

How to enter the cluster and view cluster nodes:

Use the-c option to enter the cluster: >redis-cli -c -h ip -p port

cluster info: View information about this cluster

cluster nodes: View details of nodes in this cluster

How to add cluster nodes:

syntax: add-node new_host:new_port existing_host:existing_port

Example: redis-trib add-node 127.0.0.1:7007 127.0.0.1:7001

127.0.0.1: 7007 is a new node

127.0.0.1: 7001 is an existing node (any existing master node is fine)

After adding, it is master. When adding, there is no slot. You need to re-allocate slots to this node.

>cluster nodes

Assign slots to newly added nodes: by default, newly added nodes have no slots.

#redis-trib reshard 127.0.0.1:7007

How mang slots do you want to move(from 1 to 16384)?: 500

How many slots do you want to allocate to the new node

What is the receiving node ID?

What is the ID of the node receiving the slot? --> Write the ID of the new node here

Source node: From which nodes slots are allocated to new nodes

all: represents allocation from all nodes, i.e. some are allocated from each node

Slot allocation successful:

The allocation scheme is to allocate some of the other nodes to the newly added nodes.

Set the newly added node to a node's slave:

#redis-trib add-node 192.168.2.99:7008 192.168.2.99:7001

>cluster replicate 8c381457742731bbc4d2376069d89b308c3fa5e7

8c381457742731bbc4d2376069d89b308c3fa5e7: ID for master

Note: You need to log in to the newly added node (the node that needs to be set as slave) to set it as slave.