Whitelisting local url for Firehose Webhook


We recently started getting the following warning message:

But, as currently we use feed.http-hooks pointing to a script on the same machine where we host Phabricator, we cannot use WebHooks as a drop in replacement of feed.http-hooks. This is due to local addresses being blacklisted for outbound requests in Phabricator’s:

URI “” is not a valid fetchable resource. The domain “” resolves to the address “”, which is blacklisted for outbound requests.

It is explained here that it’s done like that by design, but, what is the alternative then to using feed.http-webhooks for invoking scripts hosted in machines that are not reachable from the Internet, which only have local addresses ?

I have been searching for a way through CLI of whitelisting a single local url but haven’t been able to find something that fits.