[DRBD-user] Getting started with drbd and fedora

[Alex]

Hi,

I'm trying to understand how drbd works and how all the different
pieces go together. I first installed drbd on Linux many, many years
ago, but it appears to be quite different and obviously more mature.

I have a mail server with about 3TB of disk space for users. I'd like
to create a completely different system on a completely different
network and somehow provide a single interface for users to access
their email.

Does drbd typically work with a front-end system that helps to manage
which system is active?

Ideally I'd like a system where I can advertise a single IP address in
DNS and have traffic routed to the currently active system but I don't
really understand how all the pieces go together.

Does drbd typically involve NFS? LVM?

Is there a general overview doc that provides a description of typical
configurations?

What are the services that are available as open source as compared
with the ones offered commercially by linbit?

Thanks,
Alex