I solved this on the receiver side. I’m shipping my logs to LogDNA. In my Vector config for LogDNA, I add the Fly instance name. Then in my LogDNA config, I discard all of the extra logs and create filters to get what I want.
When I looked into the NATS subject-based messaging, it didn’t fully support my needs because of the lack of Regexp.
Here is my LogDNA sink config:
[sinks.logdna]
# General
type = "logdna" # required
inputs = ["log_json"] # required
api_key = "${LOGDNA_API_KEY}" # required
hostname = "{{fly.app.instance}}"