Solved

Is it possible to install Exchange 2010 CAS role to test before it becomes proxy for Exchange 2003 mailboxes?

Posted on 2011-03-11
6
717 Views
Last Modified: 2013-12-13
We're running into a lot of questions on exactly the CAS redirects traffic.  Here's what I know:  It becomes a proxy for all 2003 Mailboxes during coexistence with Exchange 2010/2003.  External traffic is seamlessly pushed to the 2003 front-end and mailboxes FROM CAS.

How does it route internal traffic?

Also, is it possible to install CAS without it touching the 2003 environment and simply doing a DNS change to switch it over to our production environment?
0
Comment
Question by:liquid101
  • 3
  • 2
6 Comments
 
LVL 15

Accepted Solution

by:
GreatVargas earned 500 total points
ID: 35110408
Hi,

"External traffic is seamlessly pushed to the 2003 front-end and mailboxes FROM CAS."

this is not exactlly true.. whats happens is. first you configure a parameter in cas 2010 named legacyexchangeurl that points to one external name for example https://email2003.domain.com/exchange.

after that, and if you have for example TMG publishing the sites.. you need 2 publishing rules.. one for owa 2010 and the other for owa 2003. you will also need to dns external A records, for example email2003.domain.com and email.domain.com

now.. whats the external flow?
client types email.domain.com from a computer from the Internet--> TMG forwards the request to cas 2010--> cas 2010 detects that mailbox is on 2003 and forwards the request to outside link email2003.domain.com--> tmg forwards the request to 2003 server--> client access 2003 mailbox

if must have forms based activated in 2003 server and from the client side he wont know that he is accessing email2003.domain.com

Internally this wont work.. if you access webmail internally:

-for 2003 you must type servername.domain.local/exchange
-for 2010 you must type the internalurl value configured on the cas servers for the owa virtual directory

you can install cas and the 2003 envoirement will continue to work to 2003 mailboxes. only when you start moving mailboxes to 2010 you need to set up the coexistence scenario for cas.

very important link:
http://technet.microsoft.com/en-us/library/ee332348.aspx
0
 
LVL 49

Expert Comment

by:Akhater
ID: 35110417
please read this article of mine it will save me a lot of rewriting and if you have more question please do ask

http://www.zerohoursleep.com/2010/01/installing-your-first-exchange-2010-cas-or-the-truth-about-exchange2003url-part-1/
0
 
LVL 1

Author Comment

by:liquid101
ID: 35110486
@GreatVargas

This is extremely helpful as far as internal/external users is concerned.

@Akhater

I love the article and I have printed a copy for reference, but my boss needs to know if we can actually get away with installing the CAS without redirecting traffic initially or if that happens no matter what.  With such a large organization, we really need to make sure we're good to go before jumping into this.

Essentially, we're scared that we are being forced to throw this into production without being able to test it first.  That being said, no, we're not currently able to replicate the environment in a sandbox to test.

We'd like to install the CAS, validate the install before applying the proxy to force it to the front-end.
0
Edgartown IT Case Study

Learn about Edgartown's quest to ensure the safety and security of the entire town's employee and citizen data. Read the case study!

 
LVL 49

Expert Comment

by:Akhater
ID: 35110541
no one will force you to put it in production

you can install your cas server and fix all the urls on it then bring in a test station and change on it the host file so it resolves the FQDNS entries to different ips than the one in the DNS and then, when all is working put it in production
0
 
LVL 15

Expert Comment

by:GreatVargas
ID: 35110564
yes you can install the Client Access Server and still have the 2003 envoirement functioning without problems.

I advise you to start thinking on a migration and coexistence plan, since you are on a big organization i assume that you will be using all exchange features to access mailboxes (owa, activesync, rpc over http)
0
 
LVL 15

Expert Comment

by:GreatVargas
ID: 35110601
get one mail2.domain.com url and assign it to 2010, for test purposes. also configure on 2010 the legacyurl as it is now, for example mail.domain.com

publish a rule for owa 2010 using the mail2.domain.com name

test the access from outside using mail2.domain.com and seeing if your redirected to mail.domain.com (use 2003 mailbox and i'm assuming that you have forms based on 2003. if you dont have you cant get double authentication but test anyway)

this tests that i recomended wont affect 2003 envoirement.
0

Featured Post

Does Powershell have you tied up in knots?

Managing Active Directory does not always have to be complicated.  If you are spending more time trying instead of doing, then it's time to look at something else. For nearly 20 years, AD admins around the world have used one tool for day-to-day AD management: Hyena. Discover why

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
Exchange 2010 Email server black listed 14 77
Migration from Lotus Note to Exchange 4 23
Exchange 2010 Server - Phishing attack 3 35
exchange 13 16
Learn to move / copy / export exchange contacts to iPhone without using any software. Also see the issues in configuration of exchange with iPhone to migrate contacts.
In-place Upgrading Dirsync to Azure AD Connect
Using Adobe Premiere Pro, the viewer will learn how to set up a sequence with proper settings, importing pictures, rendering, and exporting the finished product.
The viewer will learn how to successfully create a multiboot device using the SARDU utility on Windows 7. Start the SARDU utility: Change the image directory to wherever you store your ISOs, this will prevent you from having 2 copies of an ISO wit…

680 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question