Due to DNS being busted, all internal FB services/tooling that they'd use to push DNS config updates are probably completely inaccessible. Someone at FB will have to manually SSH into a production host (assuming they can even identify the right one), and issue some commands to repopulate the DNS records. They'll probably have to do this without any access to internal wikis, documentation, or code.
Keeping those poor network engineers in our thoughts.
Keeping those poor network engineers in our thoughts.