After redis is connected, a (error) noauth authentication required. error is returned after executing the monitor command

[root@m214 src]# ./redis-cli -p 6412
127.0.0.1:6412> monitor
(error) NOAUTH Authentication required.

The reason is that you did not log in with password authentication

Solution:
view the redis configuration file to see the corresponding pass.

# Generated by CONFIG REWRITE
masterauth "2651080c6814a4a9d62da69a12f962b6"
requirepass "2651080c6814a4a9d62da69a12f962b6"

Then, after logging in with redis cli, execute the command auth + password, and then execute the monitor command

[root@m214 src]# ./redis-cli -p 6412
127.0.0.1:6412> auth 2651080c6814a4a9d62da69a12f962b6
OK
127.0.0.1:6412> monitor
OK