Exchange 2003 to 2010 migration questions

I am trying to clarify a few points on our migration to exchange. We currently have three subnets all in one site. This is because all three subnets are connected via a 6mb circuit. Also...we don't really have a front end back end server in the main site has some registry hacks and is set up as a kind of fe/be dual role. That being said we have single 2003 box in each of three sites, Ill be building the cas/ht and mailbox server in the local site that is the ingress for our mail.
1) when I create the CAS and HT I need to create connections for each server
2) when creating the legacy dns namespace how do I do that to each server?
3) is TLS going to be mandatory on the smtp part?
Who is Participating?

[Product update] Infrastructure Analysis Tool is now available with Business Accounts.Learn More

I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

1.) no, exchange 2010 will create routing group connectors on install when it finds the other servers in AD.
2.) you only need legacy DNS and legacyURL if you intend to use OWA while the exchange servers coexist
3.) no, not mandatory

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today

From novice to tech pro — start learning today.