How do I connect between networks?

We have two separate networks - 10.0.x.x and 183.4.x.x and two separate domains - domain1.local domain2.local.
Both are located within the same premises  currently physically separated by individual switches.
The 10.0.x.x network is a replacement/upgrade to the 183.4.x.x network.
The domain1.local domain is AD2003, the domain2.local domain AD2008.

We want to gradually migrate users/workstations/servers/printers from the 183.4.x.x network (domain1.local) to the 10.0.x.x network (domain2.local).
Users will require access to devices on both networks/domains.
Continuity of service is paramount.

How do we set up any necessary routing/trusts between the networks/domains to allow access to all areas of the LAN during migration?
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.

One of the things to consider is to start attaching services to the main domain and then move the second one to a domain member instead of 2 AD.
I am not good with migration, but domain member will save you some time and licenses as well.
why don't you post a link to this question from windows 2003 server TA?

hope this helps!
hcd-itAuthor Commented:
Not quite sure if you understood the question.

All we are wanting to do initally is establish connection between devices in both domains.

Migration will take place later once we have established connection
You need to put a router you can use a Link sys and you open all the port for inside to outside
But to connect 2 IP segment you need a equipement to route your packet.
Big Business Goals? Which KPIs Will Help You

The most successful MSPs rely on metrics – known as key performance indicators (KPIs) – for making informed decisions that help their businesses thrive, rather than just survive. This eBook provides an overview of the most important KPIs used by top MSPs.

I was thinking that you are upgrading at the same time. but "lalanclu" has point you to the right answer a router is needed. if you are segmenting from managed switch then  you maybe able to reconfigure the network into one netwrok. but if you have 2 different provider for example T1 line and a dsl then you have to rout between the 2 networks.  
hcd-itAuthor Commented:

I get your drift. We have a Sonicwall Pro 2040 firewall that we are led to believe from Sonicwall that this will allow routing between the two networks. (Connecting each network, via switches, to 2 different ports on the firewall).

As we said, the physical networks are in the same building and can share the same cabling infrastructure - no T1 or dsl is involved.

Have you any experience on how to configure the sonicwall Pro 2040 (enhanced OS) to achieve this?
Split all the 2 network to 2 switch or 2 multiple switch. Put all 10.x.x.x to the switch A or mutiple switch A and put 183.x.x.x to the switch group B and in then you plug your Sonic wall beteween the both groupe A and B.

Open all the port from the outside to inside so if you are able turn off the fire wall on the sonic wall.
The inernal router in the sonic wall should be route your packet on the lan and you can see all the poeple and your both lan.

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
Here is the docs and guides:
hcd-itAuthor Commented:
Thanks for the help guys - your comments certainly set us off in the right direction.

Eventually setup the Sonicwall to do the routing - 183.4.x.x. on Interface 1, 10.x.x.x on Interface 3, WAN on Interface 2 and after a chat with Sonicwall, enabled the IP Helper facility within the Pro 2040 and "hey presto" communication.

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.