Build a master-slave mode cluster redis

Install stand alone reids Detailed tutorial ：https://blog.csdn.net/CharmaineXia/article/details/125297843?spm=1001.2014.3001.5502

A master node （master） There can be multiple slave nodes （slave）, A slave node can only have one master node .
Each station redis By default, they are the primary node , So only the slave is configured , Do not configure the host .

Build a master-slave cluster

All three servers are installed redis, First configure the configuration file of a slave , Then copy the configuration file to other slaves .

Method 1. The configuration file configures the slave ( permanent , Restart and take effect )

① Edit the slave configuration file
vi /home/admin/redis/redis-5.0.7/theRedisConf/redis.conf
add master Of IP Or host and port number
replicaof 192.168.xxx.xxx 6379

After configuration, restart and take effect .

Method 2. Command configuration slave （ Immediate effect , but redis The service fails when it is restarted ）

① Progress client , View current library information
redis-cli -p 6379 Or enter src perform ./redis-cli -p 6379
info replication

127.0.0.1:6379> info replication  
# Replication
role:master    # The role is master
connected_slaves:0    #  No slave 
master_replid:04caec4cc89fb5a3e5515c90f91d4e4922fe6e6b
master_replid2:0000000000000000000000000000000000000000
master_repl_offset:0
second_repl_offset:-1
repl_backlog_active:0
repl_backlog_size:1048576
repl_backlog_first_byte_offset:0
repl_backlog_histlen:0

② Set the master node of the slave
SLAVEOF The host IP 6379

View the library information after setting
info replication

# View from the machine 
127.0.0.1:6379> info replication
# Replication
role:slave    # The role becomes a slave 
master_host:192.168.60.83  # The host IP Address 
master_port:6379   # In the host redis Port number 
master_link_status:down
    
# View... In the host 
127.0.0.1:6379> info replication
# Replication
role:master
connected_slaves:2
slave0:ip=192.168.60.84,port=6379,state=online,offset=14,lag=0
slave1:ip=192.168.60.85,port=6379,state=online,offset=14,lag=1
master_replid:8e296970ccfa0ebd6dff8416e1d21d8f892d0dab

After the three sets are configured ：

Start in turn redis service , Start the master node first , After starting the slave node .
cd /
./usr/local/bin/redis-server /home/admin/redis/redis-5.0.7/theRedisConf/redis.conf

The principle of master-slave replication ：