Question : Moving from DSL to T1 need to know what I can do to minimize downtime for websites and exchange 2007

Here is my scenario
We currently use dsl and  are migrating to a 1.5 dynamic t1 connection
I have two websites, an ftp server and exchange server that I want to mimize the downtime for external access for. The websites are hosted at our main office and their dns is hosted on godaddy.

We use a sonicwall tz170 enhanced to do the nat and port forwarding.
I know that the sonicwall mappings will have to be changed and also the mx and dns records at godaddy.
What steps can be taken to minimize loss of access to the websites and external access to exchange?

Answer : Moving from DSL to T1 need to know what I can do to minimize downtime for websites and exchange 2007

Create a SECOND MX record (ideally with a lower priority) and set this with the new IP address.
What will happen is emails will try the first mail server which will work until you move to the new service, then the emails will try the first mail server, it will fail, so it will try to deliver to the second MX record, which will succeed. Once you have moved the server, delete the ORIGINAL MX record.

As for OWA, just setup a new 'A' record such as tempowa.domain.com and assign this the IP address that will be used for OWA access.

Shaun