How much storage for persistent volume for dedicated master nodes in Kubernetes?

Hi!

I'm wondering how much persistent storage is required for master nodes if we have a cluster with dedicated master nodes and data nodes? I am assuming the master nodes don't require as much data as the data nodes?

That's correct. The specific requirement depends on your cluster so it's not possible to give a concrete figure, but typically a dedicated master will run fine with just a few GB of space, often less. It's best to measure it in your actual cluster.

Thank you very much for the quick answer!

Out of curiosity, what kind of data would the dedicated master nodes store that move the requirements up to multiple GB?

It's just the cluster metadata, maybe a few copies thereof because of how it's stored. In a humongous cluster it could be ≥100MB per copy, although most clusters are a lot smaller.