How to setup IdentityServer4 to be an external identity provider

Question

There is a lot of information and documentation available regarding how to add external identity providers such as Google, Facebook, Microsoft, etc.

Does IdentityServer4 support being the external identity provider for another for another OpenID Connect server (perhaps another IdentityServer4 instance)?

If so, how do you set this up? If my IdentityServer4 instance (Instance A) is acting as the external provider for another IdentityServer4 instance (Instance B), what kind of client do I need to setup on Instance A for Instance B?

Any documentation or samples on the subject would be extremely helpful.

Answer 1

Yes, you can achieve this with IdentityServer. In this case it would work 'like' any other 3rd party identity provider (Facebook, Google, etc.)

So for example -- in this case you should configure your app with an authentication that your own identity provider exposes, instead of 'Google' -- refer to this documentation page:

http://docs.identityserver.io/en/latest/topics/signin_external_providers.html?highlight=external%20identity%20provider

You may run into issues (at least this was the case in 2017) -- see this older question IdentityServer used as external identity provider for another IdentityServer fails to properly redirect

Hopefully this puts you to the right track. Happy hacking!