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Once you have the additional application defined, you can proceed to define any new settings you need, and correcting the SP's metadata. The metadata can be taken care of first (see the following two sections). Below that, you'll find the precise rules for how settings get inherited, and some example configurations for typical use cases involving application overrides.
The built-in Metadata generator, located by default at /Shibboleth.sso/Metadata, is unable to automatically generate metadata for application overrides. You'll need to create the metadata by hand. See MetadataForSP for more information about writing your own SP metadata file
Metadata for an Existing SP
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