I stood up a new Elasticache Redis cluster today for a colleague, and he was having trouble connecting. Often in AWS this means there’s a screwed up security group, but after checking the groups, he was still unable to connect.
So I logged into the staging server in question, raised my fingers to the keyboard and…
Realised I had no idea how to talk to Redis.
Luckily, the google is only a moment away.
First, installing telnet
The telnet client is not available by default, and I don’t install it at provision time. So from the PowerShell prompt, which is all I have available in Windows Core, I need to install it with Install-WindowsFeature.
Now, OK, so how do I connect to Redis?
telnet open redisclusterdnsname.amazonaws.com 6379
Best bet: issue the MONITOR command. This will give you a nice test of what’s going on in the cluster, and convince the developer standing at your left shoulder that yes, their web server can indeed talk to Redis.