Contrail Metadata requests containing the "Connection: close" header fails. This issue was discovered while operating a custom OpenStack distribution, in which Envoy is used as the load balancer for OpenStack API services, including metadata requests.
The failure occurs because Envoy normalizes HTTP header keys to lowercase, the metadata service does not respond correctly when the response contains a "content-length" header.
Contrail Metadata requests containing the "Connection: close" header fails.
This issue is fixed in Contrail 21.4.L5 release.