Reuse web app address after migration

Question

I have a web app on a SharePoint 2010 farm, that we use for our internal intranet example “intranet.company.com”

We would like to build a 2013 farm, but pilot its development in the early stages so that we can learn from a gradual shift over of teams and content, instead of all at once. I know it may seem like a lot of extra work moving content over in this way, instead of attaching the 2010 database to the new farm, but there is a lot of orphaned content that we would like to leave on the old farm database and we hope to start fresh with a new one.

With that said we would like to keep both 2010 and 2013 running, am I incorrect in my understanding that if my 2010 farm is using a web app with the address “intranet.company.com”, that I cannot use this for any 2013 web app I create as it would create a conflict in DNS?

If i am correct in that understanding, my concern is that we would eventually be migrating users and traffic away from the old web app “intranet.company.com” in 2010 as it would now be going to the 2013 farm instead. So am I forced to abandon the 2010 farm address of “intranet.company.com” once it is no longer needed and have people start using a new address for the 2013 farm of, for example, “newintranet.company.com”?

Is it possible that i would be able to replace the 2013 address with the 2010 web app address, once it is no longer being used? Is this something I have to configure in the web app or is there some DNS trickery? Any issues with attempting this type of operation in general?

Answer 1

For the most part, John is correct. However, if you have some hardware handling your DNS, such as an F5 box, it is possible to create rules there that will route requests to one farm or another based on the site URL being requested. For example, a rule could be created that would route all //intranet.domain.com/sites/SiteA to 2013 while requests to //intranet.domain.com/sites/SiteB could be directed to your 2010 farm.

We did this for our 2007 to 2010 migration and it worked well. The only catch was that we had to point //intranet.domain.com/ to the newer farm so that it could properly serve supporting files, like CSS and Javascript.

Answer 2

While your 2010 farm is using intranet.company.com, your 2013 farm cannot use it. While both are running, your 2013 farm would need a new address.

Once you decommission your 2010 farm, however, you can assign the 2010 DNS entry to your 2013 farm and configure an Alternate Access Mapping to accept that DNS alias.