You can set up a repository to automatically have its branches, tags, and commits updated from an upstream repository.
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When creating a new project, you can enable repository mirroring when you choose to import the repository from "Any repo by URL". Enter the full URL of the Git repository to pull from and click on the Mirror repository checkbox.
For an existing project, you can set up mirror pulling by visiting your project's Settings ➔ Repository and searching for the "Pull from a remote repository" section. Check the "Mirror repository" box and hit Save changes at the bottom.
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Yes, web browsers does a DNS lookup and uses that ip address for the connection. They also take the original host name and send it as part of the Host http header. This allows a web server to serve multiple web sites from the same ip address.
Best Answer
Enabling the sourcerepo.googleapis.com API on the project solved it.