I’ve been stuck with the same issue, and the preceding answer did not help me (albeit well written).
The solution is here : check your /etc/redis/redis.conf, and make sure to change the default
bind 127.0.0.1
to
bind 0.0.0.0
Then restart your service (service redis-server restart)
You can then now check that redis is listening on non-local interface with
redis-cli -h 192.168.x.x ping
(replace 192.168.x.x with your IP adress)
Important note : as several users stated, it is not safe to set this on a server which is exposed to the Internet. You should be certain that you redis is protected with any means that fits your needs.