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Cisco Bug: CSCtc89566 - Authentication using alternative UPN suffix fails in AD multi-forest

Last Modified

Oct 19, 2016

Products (1)

  • Cisco Secure Access Control Server Solution Engine

Known Affected Releases


Description (partial)

ACS does not support user authentication in AD when a user name is supplied with an alternative UPN suffix configured in multi-forest.

Steps to reproduce:
1. Configure a trust between two AD domains ( and
2. Configure an alternative UPN suffix in one domain ( in
3. Create a user with alternative suffix in the domain (
4. Configure ACS to join another domain (
5. Perform an authentication with the user given alternative UPN suffix ( The authentication will fail.
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Bug Details Include

  • Full Description (including symptoms, conditions and workarounds)
  • Status
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