I can't addurl a file because there is a special remote which is not available. I can see that git annex is asking it if it wants to claim the url which it doesn't. I don't feel addurl should depend on the remote after CLAIMURL-FAILURE. Or do I miss something?
git annex --debug --verbose) and your config files (git config --list)? (Redact any sensitive info). Maybe,annex.security.allowed-ip-addressesexcludes the IP address of the URL, so the built-in web remote never gets a chance to claim the URL? I recall running into something like you describe, and the issue was with some config setting I had.If the special remote responds with CLAIMURL-FAILURE, then addurl will not use it.
There might be some other way the special remote could fail that breaks addurl. The only one I can see currently is if the special remote sends something that's not a valid response in the protocol.
So I second Ilya, we need a protocol dump or a better explanation about what behavior you are seeing.
Apparently it happens when the remote returns PREPARE-FAILURE (in this case due to insufficient internet connection). So we get back to PREPARE-LOCAL and external_remote_querying_transition.
I'm going to change git-annex-remote-googledrive to defer network connection to when when it's needed. But as external remotes are encouraged to establish network connections in PREPARE, something should be done on git-annex's side, too.