Today, we had a SWIFT media storage backend outage at Wikimedia Commons. As a result, file uploads failed. But also file move operations had issues:
was moved during this time and the (binary) file simply "vanished". The (binary) file remained where it was before in the backend but the file description page was moved and the link in the file revision table pointed to something that did not exist. Consequently, no thumbnail could be generated.
I hope that I did not mix up any terminology. If there are questions, please let me know swiftly (as I regulary erease my short-term storage) :-)