Both Local and Remote Redis server erroring out "Error: Redis connection to 127.0.0.1:6379 failed"

We have a node/express app using Kue that has been running for 3 years. Literally running on an Unbuntu EC2 server for 3 years (never restarted or rebooted). We have never had any issues with it other than truncating the redis log file as it was eating up memory. We used the local Redis dev server that comes with kue.

In the December of 2017, the Node/Express/Kue server would stop working.

Error: Redis connection to 127.0.0.1:6379 failed

We switched to using Elasticache M3 3G redis instance. It worked fine for 2 or 3 days then it started giving us

Error: Redis connection to 127.0.0.1:6379 failed

Now we are back to having to reboot our EC2 server instance running our Node/Express/Kue app. We reboot it and it goes back up.

It can't be the Redis server as both local and remote end up with the same issue. Any chance some new security update on EC2 has caused issue with Kue access Redis (local or remote)?

No file or test is named. Start by reproducing the Redis connection failure with both the local Redis server and the AWS ElastiCache setup, then inspect Kue's Redis connection handling; done means the cause is identified and a verified fix or prevention is documented.

Written by the indexing model from the issue text.