E0020

A deploy was refused because the image uses a host call this host does not serve.

Erroneous example:

$ crab deploy
Error: 422 [E0020]: this host does not serve berm.http.fetch.v2

The host reads the image's Wasm imports and refuses deployment if it cannot serve one. This can mean the image uses a newer berm-lang or needs an optional host capability, such as an HTTP proxy, that is not configured. Nothing is deployed, and the service keeps running what it ran.

To deploy it:

• Build it with the berm-lang version the host runs. crab inspect <service> prints the version and host calls of what's deployed.
• On the local host, update crab and deploy again.
• If the missing call needs an optional capability, deploy to a host configured to serve it.