What is the difference between seed and persistent-peers?

When bootstrapping, is it possible to bootstrap only with a list of persistent-peers and no seed or vice versa?

Are both mandatory when developing with cosmos-sdk?

Thanks!

Seeds you connect to for a short periods of time to get updated lists of peers, persistent peers you attempt to connect to continuously.

Seeds were not working reliably for a long time but @jaekwon just fixed them in the most recent Tendermint release candidate so you don’t need anything other any seeds to bootstrap anymore.