Ok, Josh @defensivedepth had the right answer. But for anyone else who struggles to find the right documentation, I'm putting the solution I found here: https://github.com/kolide/fleet/blob/master/docs/infrastructure/fleet-on-ubuntu.md Look at that link for the section about redis, it is literally two lines to get it running, of course you'll then need to make it run properly (adding it to auto start as a service on the system in the same way as you would have done for fleet itself). But, that wasn't all I discovered. I've got Ubiquiti UNMS running on the same server, and UNMS is packaged with redis as well, both bits come together as a single installation, but they are achieved through two separate docker containers (actually it might be more than that). In any case, I had a docker container called unms-redis already running and using the standard redis port of 6379. Strangely though fleet was unable to use that. Not to worry, I realised that it was probably a bad call to rely on UNMS to always use redis in the future, since their installation installed redis, if they decide in the future to not use redis and remove it, then it would break my installation of fleet. So I installed another redis service with a different port and adjusted the redis settings in the fleet.yml file, and hey presto it worked. thanks again Josh!