SP3 multiple vhosts with acs index

[Peter Schober]

* VANNIER, LAURENT <laurent.vannier at airbus.com> [2021-06-16 15:42]:
> When using acsindex="1" or "2" in the SSO object (or through query params),
> it seems possible to provide the required value in the authnrequest for
> each vhost.
> However, when using acsindex="3", I get an error 500 with message "artifact
> binding selected for response, but identity provider lacks support" in the
> logs without the authnrequest being generated.

That's why relying on acsIndex to identity the endpoint is deprecated,
I guess. I'd expect the ACS index value at the SP differ from what the
IDP has for that IDP.

-peter