Prometheus data retention?

[lostngone1]

It looks like Prometheus's data retention default is 15 days. Is there an easy way to change that(looking to store ~30 days)?

I am not an expert on containers or Prometheus.

Thank you.

[mtflynn2011]

I think the right option for Prometheus is: --storage.tsdb.retention.time=12d (or however many days you want)

I've been trying to add:
--storage.tsdb.retention.time=365d
as a command-line option to prometheus without success.

I've seen things online that suggests adding a "command: - '--storage.tsdb.retention.time=365d' to the docker-compose.yaml file is the way to go. But, Prometheus doesn't seem to start up right when I do this.