Is it possible to use the same Shib IdP for multiple domains?

[Peter Schober]

* Shoji Kajita <kajita.shoji.5z at kyoto-u.ac.jp> [2022-12-20 16:07]:
> We are looking for a way to use a single Shib IdP for multiple custom
> domains (ex. a.kyoto-u.ac.jp and b.kyoto-u.ac.jp)

That could mean different things: Do you need to have the IDP
accessible with different host names? Does that IDP serve communities
with differing DNS domains as attribute values (and are these
attributes "scoped" in the Shibboleth and SAML SubjectID Attributes
sense)? Do you need the IDP to behave differently depending on what
URL it has been accessed with?  etc.

In the simplest case you'd have/keep the IDP running at a single host
name, with a single, static UI/branding. Such a setup could still be
used to assert data/attributes (e.g. mail or
eduPersonScopedAffiliation or SAML SubjectID) with different DNS
domains as part of the value(s).
If "scoped" attributes are relevant to your use cases or communities
then your IDP would list all/any domains it's asserting attribute
values in as part of its own metadata (shibmd:Scope element).

HTH,
-peter