While creating a SAML application, if the specified entity ID is already in use by another service provider, Access Manager prompts to specify a different entity ID or a unique ID. You must specify a different entity ID or a unique ID to create the application.
Consider the following points while specifying a unique ID:
A unique ID can contain numbers, alphabets, special characters or combination of all.
A unique ID must not contain spaces.
A unique ID must not contain patterns uniqueid or naminstance (case-insensitive).
A unique ID must be unique among all unique IDs available for different SAML 2.0 service providers in the Identity Server cluster.
Adding a unique ID changes the Access Manager identity provider’s metadata, such as single sign-on endpoint and entity ID, for that service provider. The service provider uses this new metadata for establishing federation with Access manager.
Later, if you change the unique ID, you must reimport Access Manager identity provider’s new metadata for that service provider.
For more information, see Creating Different Instances of a SAML 2.0 Service Provider in an Identity Server Cluster
in the NetIQ Access Manager Appliance 4.4 Administration Guide.