To have more control over the IP IdP Discovery, you can create your own WAYF selection page and integrate it in your service. It goes as follows:
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Line 3 contains the Service Provider metadata of 'https://test.test.nl', line 4 the metadata for a coupled Identity Provider (SURFnet Test IdP). For simplicity the remainder of the XML metadata is omitted.
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Shibboleth
When you use Shibboleth, the following HTML code presents a link that will start an authentication to a specific IdP:
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