When a server certificate is issued by an intermediate certificate authority, and the client lacks those intermediate certificates, the server should provide all the relevant certificates to the client. This allows the client to verify the final certificate in the chain against the root certificate.
When a server certificate is issued by an intermediate certificate authority, and the client lacks those intermediate certificates, the server should provide all the relevant certificates to the client. This allows the client to verify the final certificate in the chain against the root certificate.