Does Maker Edition allow gateway redundancy? I'm getting a "This platform edition does not support redundancy." error when I try to set a gateway as a master.
Nope, it's just as the error is telling you.
That sucks. Is there any reason for this limitation? It would be really nice to have redundancy for Maker- I'm running my home server on old second-hand hardware so it's more of a question of when a node is going to fail 
The software is free. Take regular backups.
@Matrix_Engineering is right. My current methodology is:
- Automated gateway backups
- .gwbk files get backed up to a separate location
- In the event of a failure, either spin up a docker container or install Ignition on another server
- Configure the new server to look like the old one, if required (e.g. IP address, etc.)
In my case this should take less than 30 minutes which is more than acceptable in my setup 