19_ Redis_ Manually configure the host after downtime

Master slave configuration mode ：

Model a ：

Model 2 ： Caterpillar type

If there is no boss (6379 It's down. ）, Can you choose a boss to come out at this time ? Before sentinel mode comes out , The operation of selecting the boss needs to be completed manually
Configuration command ： In the surviving slave 6380 Carry out orders ：SLAVEOF no one
If the host is disconnected , We can use SLAVEOF no one Make yourself a host ! If this is the time for the boss to repair （6379 restart ）, The boss is the barehanded commander , Need to reconfigure !