Shibboleth service provider supports two entityIds for same ACS endpoints

[Peter Schober]

Kannan, Satheesh (ELS-CON) via users <users at shibboleth.net> [2024-12-02 09:51 CET]:
> How would request/response even work with that; when sending a
> request, we wouldn't necessarily know which of the two issuers does
> the IdP trust?

Well, obviously you can't start using a new/different entityID before
having made sure you propagated metadata for this entityID (it's
essentially a new/different SP) to all the IDPs you intend to use the
new/different entityID with.

> Intention for this, slowly migrate from old to new service provider
> entityIds without impacting identity providers/users?

You'd register/publish/distribute new metadata as if you were adding
another SAML SP -- because that's effectively what you're doing.

HTH,
-peter