In addition to @AdrienneCohea great comment, I will some other discussions around this topic:
- Question: What could go wrong if a nomad server and client ran on the same host? 路 Issue #5053 路 hashicorp/nomad 路 GitHub
- Can I run both nomad client and server on the same machine?
- Is there a low resource configuration or distribution of nomad (like k3s) or can it be run on a single weaker machine?
In summary, it all depends on your specific requirements, and each choice presents their own trade-offs.
Co-locate servers and clients may impact each component performance and present a possible security issue since you will be allowing arbitrary workloads to run in servers through the clients.
Using a single server will impact your available and you will need to be extra careful with backups and restore.
You will need to asses these impacts and see which ones you are acceptable to your situation.