what's the frequency of the letter "h" in:
q: unable to connect to redis using gcp external ip i followed the following instructions and installed a redis-server on gcp.
https://cloud.google.com/community/tutorials/setting-up-redis
i set the firewall so that port 6379 is open to all ip (0.0.0.0/0)
i then create another gcp instance in the same project. when i tried to connect to the redis-server i just setup(say on a machine with 1.2.3.4 externam ip), i was not able to do so. but when i use that machine's internal ip, it worked.
also, when i tried to connect to the redis-server on my local machine, it failed(timeout).
when i nmap the machine with port 6379 from another instance in the same gcp project with the machine's external ip it shows
port     state    service
6379/tcp filtered unknown

when i nmap the machine with port 6379 from another instance in the same gcp project with the machine's internal ip it shows
port     state service
6379/tcp open  unknown

when i nmap the machine with port 6379 from my local machine in the same gcp project with the machine's external ip it shows
port     state    service
6379/tcp filtered redis

what am i missing here?

a: i finally figured out what went wrong. 
i was not setting the correct target. 
i thought i could just type anything in the target field, but it turns out what goes in that field will be the machines the rule applies to. 
after i selected all instances in the network for targets everything went well. though when i nmap from internal network, port 6379 is still an unknwon service, but it's open and i can use redis-cli to connect to the redis server

user
I counted sixty-six "h"s in that text.
assistant