Just attempted to do this with the existing documentation, and I had a nightmare of a time. The Microsoft TechNet articles were pretty good, and the checklist here is helpful, but navigating back and forth through the different pages was difficult. The video HERE made it look really simple but some steps didn’t work quite as easily as I’d hoped, and it left out some key setup steps. I’m going to go through all the steps as it ended up working for me. I did a database attach upgrade from one server to another, setting the existing site to read only so that no changes could be made during the change. I’m also using port 8080 as well as the traditional port 80.

PREPARATION

Run the upgrade checker. I don’t have a whole lot of advice here, as mine ran clean. I have a fairly simple installation with one site and it is basic.

SETUP

On the new server download Sharepoint Foundation Server 2010 from here, and the SQL Express 2012 Management tools from here. Run the Sharepoint Foundation Server Installer. This will give you a menu, where you can install the prerequisites including Sharepoint Server 2008. Once this is completed, Run the Sharepoint Foundation Server Installer. Finally, run the SQL Express 2012 Management tools installer. All of these are pretty straightforward installers with little to no options. Once all of that is installed Run the Sharepoint Foundation Server Configuration Wizard. This will automatically setup the default site and settings. At this point if there are any customizations or features that need to be applied, this would be the time to apply them.

DATABASE BACKUP

On the existing installation, open the Central Administration for the Sharepoint site. Go to application management, then Content Databases. Make note of the database name for your site. Open SQL Server Management Studio Express and locate the database previously noted, I’ll refer to it as WSS_Content_a1. Right click WSS_Content_a1 and go to properties. Select Options from the left pane, and scroll down on the right pane to Database Read-Only, set it to true, and click ok. Now that the database is set to read-only, right click on it again, and select tasks, then back up. Ensure backup type is set to Full, and add a destination to back up to, including a file name ending in .bak. Once the backup completes, move the .bak file to the new server.

DATABASE UPGRADE

On the new server, open SQL Management Studio. Right click on Databases and select restore database. Select “From Device” and locate your .bak file, click ok to start the restore. Once the restore completes, some work must be done in powershell to prepare sharepoint and upgrade the database.

Open the Sharepoint 2010 Central Administration Site. Locate the database associated with the default site and make note of the database name. I will refer to it as WSS_Content_b2. Open the Sharepoint 2010 Management Shell. You will need to dismount the database that was created for the default site, and mount the database from your old site.

First to dismount the default database run, replacing WSS_Content_b2 with the database noted.

dismount-spcontentdatabase WSS_Content_b2

Then test your old site database, replacing WSS_Content_a1 with your restored database, and servername with your server name.

test-spcontentdatabase -name WSS_Content_a1 -webapplication http://servername/

If the test returns errors, research them and decide if you want to ignore or fix them. Once you are ready, mount your database to the site, again replacing with your own values.

mount-spcontentdatabase -name WSS_Content_a1 -webapplication http://servername/

This will put a percentage complete below the command, you can also check the status in the upgrade section of the Sharepoint Central Administration Site. Once the upgrade is complete, check the upgrade section of the Sharepoint Central Administration Site for information about any errors that may have occurred and to see the success or failure status.

Now when you browse to the default site, your site should appear. Once you have confirmed that is working, you can move on.

CONFIGURING PORTS  

This was a little tricky for us, as our client accesses the site on port 8080, internally and externally. To configure this, go to Application Management, then select Configure alternate access mappings.  The default should have and internal URL of http://servername and a Public URL for Zone of http://servername. The Intranet zone should have and Internal URL of http://servername:8080 and a Public URL for Zone of http://servername:8080. If you are accessing this via a web address as well, enter an Internal URL of http://my.sharepointsite.com:8080 with a Public URL for Zone of htpp://my.sharepointsite.com:8080, with a zone of Internet.

NOTES: change 8080 to whichever port you wish to use. Keep in mind for the external web address you may have to adjust your firewall rules to point to your new server. You may also need to adjust your DNS settings.

Finally, go into Web Applications, select Manage Web applications. Select your default site then click on “extend” from the ribbon. In the Create a new IIS web site Name, enter change the numbers following sharepoint to 8080 (or whichever port you are using). Change the port to 8080 (again, or whichever port you are using.) Finally, scroll down and change the URL to http://servername:8080/ and leave the zone at internet, click OK to apply.

VOILA! Test internally and externally to confirm it works and celebrate your success!