$ redis-cli -h 127.0.0.1 -p 6379 info
# Server
redis_version:4.0.2
····
····
····
····
# Cluster
cluster_enabled:0

# Keyspace
db0:keys=4,expires=0,avg_ttl=0
#可以直接输出信息

$ redis-cli -p 6379
127.0.0.1:6379> config get requirepass
1) "requirepass"
2) ""
#表示没有设置密码

127.0.0.1:6379> CONFIG SET requirepass redis123
OK

$ redis-cli -h 127.0.0.1 -p 6379 info
NOAUTH Authentication required.
$ redis-cli -h 127.0.0.1 -p 6379
127.0.0.1:6379> info
NOAUTH Authentication required.
127.0.0.1:6379> auth redis123
OK
127.0.0.1:6379> KEYS *
1) "backup3"
2) "backup4"
3) "backup2"
4) "backup1"

$ vim /data/redis/conf/redis.con
requirepass redis123
#重启后生效