Attaching Vault to a new Exchange in a new Domain

[airwolph]

Hello, 

We are in the process of splitting up two organizations, for ease let call the existing site a and new site b. 

Gen info
The challenge - trying to move users from site a to b with reduced mailbox sizes
We currently have Symantec Vault installed in Site a
Site a is running exchange 2003
the users being moved to site b were un-vaulted in preparation for exporting their pst's

Details
Site b is built with a new domain and exchange (2010)
site a and b have a two way trust. 

Our proposed plan

build a new Symantec vault server on site b
connect the site b vault to the site a exchange(2003) server
archive the mailboxes for all the users in site a that are moving to site b
Migrate the users mailboxes to the new exchange(2010) on site b
after migration, attach the vault on site b to the exchange (2010) on site b (this is where we're not sure)

Question:

Are we out of luck, is this even possible, if so can someone please point me to the documentation for this?

would be greatly appreciated.

thanks in advance.

[JesusWept3]

use SynchinMigrationMode
http://seer.entsupport.symantec.com/docs/284956.htm

[GertjanA]

Exchange2010 can only be archived by EV9, expected Q2 2010.

Best way....

Wait for EV9. Upgrade Site A to EV9, install EV9 in B
Archive users in A. When moving to B, use the ' move archive feature'  to move archives to the new site.

What you describe...
The archives will have permissions set to users in site a, not b. You archive, move user, then you loose permission....

But, you still have to wait for EV9 to archive Ex2010 mailboxes.

[MichelZ]

Hi

- Raise quota on the new exchange
- Move mailboxes
- Wait for EV9, then install it on the new site and archive the mailboxes
- Lower quota then

/Michel

[airwolph]

Thanks for the suggestions everyone, greatly appreciated!

To clarify, one of the objectives is to reduce the mailbox sizes before moving them - the idea being to lower the amount of time to migrate users (currently have approx 60ppl on a 250gig store) - we want to get it down quite a bit before moving them.

Do I have the EV9 limitation if I only intend to use the current version on 2010 to allow users to retrieve the old items? I have no intention of archiving them immediately after migration, just using this as a method to lower the mailbox sizes and allow them to click on placeholders to still retrieve archived emails.

thanks again