Processing HTTP_Redirect from idp

[Peter Schober]

* Will Knight <wknight at quavermusic.com> [2018-11-02 16:23]:
> We are in a precarious state where we need to serve thousands of users and
> we want to switch them over to a new SP, *seamlessly*.  Our plan was to
> change DNS records/bindings so that their login links point to the new site
> - but we want to do that with as much confidence as possible.  Do you have
> any recommendations?  I realize this question might be outside the scope of
> this forum.

You can test all this beforehand without changing DNS by configuring
the new server identical to the old one, esp wrt its canonical name
and vhost config and the SP's entityID and keys, and simply point the
existing host name to the new server's IP address in your local[0]
hosts file.[1]

I also wouldn't even change DNS but instead move the IP adresses of
the old system over to the new.
If that's not an option make sure to lower the TTL on the relevant
zone well before the change.

-peter

[0] I.e., where your web browser runs.
[1] https://en.wikipedia.org/wiki/Hosts_(file)