```lang=bash
> echo '{"client": "arc", "clientVersion": 4, "user": "josh"}' | ../arcanist/bin/arc --conduit-uri=http://phabricator.local --conduit-version 2 call-conduit conduit.connect
Waiting for JSON parameters on stdin...
{"error":"NEW-ARC-VERSION","errorMessage":"NEW-ARC-VERSION: A new version of arc is available! You need to upgrade to connect to this server (you are running version 4, the server is running version 6).","response":null}
```