One Does Not Simply Migrate a 20GB website

I’m preparing to migrate a large WordPress multisite and we’re running into several unexpected challenges along the way.

• 32 bit PHP is restricted to creating a 2.1GB archive.
• We have some other server side problems completely unrelated to WordPress
• We self host on campus
• Duplicator Pro is fantastic at helping me uncover and resolve these conflicts along the way.

Multisite really keeps me on my toes ????