I've got a customer needing to move their SharePoint 2010 install to a new domain, I've done some reading and looks like I can mount the content DB to a web application which I've basically setup in the same way as the current one then get into it by altering the site collection admins for its site collections. The main issue is that I believe the AD user migration will generate new SIDs for the accounts in the new domain so I will be looking at having to run something like this:
Move-SPUser –Identity olddomain\UserName - NewAlias newdomain\UserName
The customer has given their new domain the same NETBIOS domain name as the old one. I know this is somewhat a bit hypothetical at the moment but will I even be able to run the cmdlet above?
Edit: 04/09/2012
I undertook this exercise today with some mixed results using this post and slightly modified script where it links to The Easy Way to Restore a SharePoint 2010 Content Database to a Different Domain, whilst the user accounts that existed in the new domain appear to have gone through the AD Groups when attempting to execute Move-SPUser on those throw the following error:
Move-SPUser : Operation is not valid due to the current state of the object.
At line:1 char:12
+ Move-SPUser <<<< -IgnoreSID -Identity $user -NewAlias DOMAIN\domaingroup
fcontentapprovers -confirm:$false
+ CategoryInfo : InvalidData: (Microsoft.Share...PCmdletMoveUser:
SPCmdletMoveUser) [Move-SPUser], InvalidOperationException
+ FullyQualifiedErrorId : Microsoft.SharePoint.PowerShell.SPCmdletMoveUser
This web application is just using classic mode auth and most of the topics I've found on this error related to claims based or moving to claims based auth. I've had to work around this by adding other AD groups with the same membership into the existing SharePoint groups. But this is messy.
This site is running just SharePoint 2010 SP1 at this point in time, I have read that there were some changes that came out for the move-spuser cmdlet in the June 2011 CU so if anyone is aware of that improving the situation I might apply the August 2011 or June 2012 CU.