Looks like 4th gen petabox, of which several racks where at ISC (isc.org) in Redwood City; but even well over a decade ago, there where at least 10 racks there already :)
Brewster Kahle (npub1ftl…3e6s) how much documentation is there actually about the growth and history / timeline of the Internet Archive itself?
a few finds:
https://blog.archive.org/2010/07/27/the-fourth-generation-petabox/
https://archive.org/web/petabox
https://www.bibalex.org/en/MediaGallery/Default/internetarchive