What could empty the Redis database (clear all keys)?

[fatso83]

This questions concerns the basic Redis structure and how Resque operates on that, since I am not able to find out how this is dealt with. I am not familiar with Resque, but know how to work with Redis using the redis-cli.

My question:

We have a very low traffic Resque job queue (typically a few jobs a day) on a system not set up by me, with no monitoring whatsoever, and yesterday I was told no emails were being sent out. The Symfony logs were empty and I had nothing to go by, so I logged into the instance running Redis and found NOTHING. Doing KEYS * returned nil. That was scary, as I thought that even no jobs would at least list a few resque keys? Like resque:stat:failed, resque:workers, resque:queues, resque:stat:processed, resque:failed and so forth.

I then found the /data/dump.rdb file and ran strings on it: https://gist.github.com/fatso83/91e6b9ea0c977cabe949574bce08b778

From what I know, this is supposed to contain a persisted dump of what is in-mem and this dump was definitely NOT empty. It contained lots of interesting strings (see the link above to the redacted output).

Is it normal to have no keys in a working Resque Redis database or is this a sign of something going very wrong? Should I try restoring it or what do I do here?

My Environment

• PHP-Resque version: "chrisboulton/php-resque": "dev-master" (yes, super old, but the disk layout should not have changed, right?)
• PHP version: 7.4
• Redis version: 3
• Server type and version: AWS ECS instance, Docker container
• Operating System and version: Linux