Set up redis highly available cluster environment

First, set up a stand-alone version Redis Environmental Science , Please refer to my blog ：Centos7 Build in Redis Environmental Science

1、 preparation

When it's set up , In the catalog /usr/local/redis/ Next , newly build myredis Catalog

mkdir myredis

Get into myredis Directory , newly build 6 A folder , Use the port to name , for example ：

mkdir redis7000

…

mkdir redis7005

So now we have 6 A folder

2、 Basic configuration information

We from /usr/local/redis/bin/ Under the table of contents , Copy a configuration file , Modify the configuration

#  port 
port 7000

#  Daemon mode starts 
daemonize yes

#  Externally connectable , Cloud server , Just write on the intranet 
# bind 127.0.0.1

#  Externally owned IP Address access 
protected-mode no

#  Process documents , Differentiate by port number 
pidfile /var/run/redis_7000.pid

logfile “/usr/local/redis/myredis/redis7000/redis.log”

#  Persistent file storage location 
dir /usr/local/redis/myredis/redis7000/

3、 Cluster configuration information

#  Start in a cluster 
cluster-enabled yes

#  Cluster configuration information file 
cluster-config-file nodes-7000.conf

#  Timeout time 
cluster-node-timeout 15000

cluster-replica-validity-factor 10

cluster-migration-barrier 1

preservation , sign out

4、 Copy profile

We have changed it 7000 Configuration file of port instance , We use commands , Mass replacement

sed 's/7000/7001/g' redis7000/redis.conf > redis7001/redis.conf

…

sed 's/7000/7005/g' redis7000/redis.conf > redis7005/redis.conf

That's right. redis7001 I got a share in it redis.conf file , The port inside is from 7000 replaced 7001, Repeat the command

5、 Boot instance

/usr/local/redis/bin/redis-server /usr/local/redis/myredis/redis7000/redis.conf

…

/usr/local/redis/bin/redis-server /usr/local/redis/myredis/redis7005/redis.conf

…
start-up 6 An example , see redis Operation of the

ps -ef | grep redis

It can be seen that , All instances are started in a cluster mode

6、 Create clusters

/usr/local/redis/bin/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

• –cluster-replicas 1 Indicates the master-slave ratio 1：1, In this way, we get a cluster environment with three masters and three slaves

7、 Sign in Redis

/usr/local/redis/bin/redis-cli -h 127.0.0.1 -p 7000

View node information

cluster nodes

You can see Node information of three masters and three slaves

8、 Add a node

• 1、 Add master

/usr/local/redis/bin/redis-cli --cluster add-node 127.0.0.1:7006 127.0.0.1:7000

• add-node： Add a node
• 127.0.0.1:7006： Added node ip:port
• 127.0.0.1:7000： Any node of the cluster already exists ip:port

• 2、 Add slave node

/usr/local/redis/bin/redis-cli --cluster add-node 127.0.0.1:7007 127.0.0.1:7000 --cluster-slave --cluster-master-id nodeId

• add-node： Add a node
• 127.0.0.1:7007： Added node ip:port
• 127.0.0.1:7000： Any node of the cluster already exists ip:port
• –cluster-slave： Add as slave node
• –cluster-master-id： Master node id

9、 Capacity expansion

Our cluster has the concept of slots , left-off key After passing the algorithm , Determine which node it will eventually be stored in , The total slots are 16384 individual , from 0 - 16383.

/usr/local/redis/bin/redis-cli --cluster reshard 127.0.0.1:7000

• reshard： Assign slots
• 127.0.0.1:7000： Any node of the cluster already exists ip:port

Input ： Allocate the size of the slot , This depends on the actual situation

Input ： The distribution of nodeId

Input ： From which master Nodes are allocated , There are three options ：all（ All , Average distribution ）、nodeId（ Of a specific node id）、done（ The final allocation is completed ）

Input ：yes

10、 Shrinkage capacity

/usr/local/redis/bin/redis-cli --cluster reshard --cluster-from outNodeId--cluster-slots quantity inNode ip:port

• outNodeId： Migrated nodes id
• quantity： The amount moved out
• inNode ip:port： Immigrated ip:port

Input ： Received nodeId
Input ：yes

11、 Delete node

/usr/local/redis/bin/redis-cli --cluster del-node 127.0.0.1:7000 nodeId

• 127.0.0.1:7000： Any node of the cluster already exists ip:port
• nodeId： Of the node to be deleted id

Be careful ： The slave node should be deleted first , Delete the master node again

If you find deficiencies in reading , Welcome to leave a message ！！！