JS and Core Can Use a cluster together

[ltDamon]

If I want to use these two features at the same time，JetStream and Core. I must to deploy two cluster?

[wallyqs]

You can use both at the same time with the same cluster.

[ltDamon]

It said where none of the nats-server instances are configured to enable JetStream. Just wanna check if i enable the JetStream. it affect the affect efficiency of "core nats".

[ripienaar]

Enabling jetstream will increase memory use on the server - and using it again also will increase memory use.

But core nats performance will remain the same essentially