How to migrate post media from stand-alone to multisite build

by

Here’s the process we used to migrate the media and keep it in sync with the posts.

  1. We used the Export media with selected content plugin to export our posts. Piecing off the export into smaller chunks. As suggested by Matt Whiteley.
  2. We manually moved (via ftp) the /wp-content/uploads/{year} directories to the ‘same location’ on the multisite build. This may present a problem if you already have a lot of media in the default site, as you’ll have to mix content. Fortunately our default site is just a placeholder, so we didn’t have much media/content overlap.
  3. We imported the exported xml using the default WordPress Importer (still in chunks).
  4. The posts imported with all the media! Yay! There were probably a handful that didn’t work, but overall it got most everything.
  5. We removed the migrated /wp-content/uploads/{year} directories, as the import process added the media to it’s new, proper, home /wp-content/uploads/sites/{site-identifier}/{year}

Resources
Matt Whiteley’s Move WordPress blog posts with featured images was crucial
Export media with selected content plugin was crucial
WordPress Importer