Settings That Impact License MAC Address on Cisco UC Servers

UPDATE (January, 2018) – This article applies to the following Cisco UC Products:

  • Communications Manager – 5/6/7/8
  • CUPS / Instant Messaging & Presence – 5/6/7/8
  • Unity Connection – 5/6/7/8
  • Emergency Responder – 5/6/7/8/9
  • Contact Center Express  – All versions

Cisco’s Linux based UC apps are bound to a ‘virtual’ mac address (aka license mac address) assigned to the server, rather than the logical mac address assigned to the physical interface. The license mac address is based on several parameters, which are listed below, and changing of any of these parameters will change the license mac address. Changing the license mac address voids the existing license file so a new license file must be obtained from the Cisco Licensing group. Cisco provides a 30-day grace period for obtaining a new license; however, if a new license is not loaded onto the server and validated within that 30-day grace period, the application services will stop and the system will fail until a new license file is loaded.

License MAC is dependent on some system parameters. Modifying any of these parameters can change License MAC thereby invalidating current License files. Here are the parameters on which the validity of a License MAC depends:

  • Time Zone
  • NTP Server 1 (or ‘none’)
  • NIC speed (or ‘auto’)
  • Hostname
  • IP Address
  • IP Mask
  • Gateway Address
  • Primary DNS
  • SMTP Server
  • Certificate Information (Organization, Unit, Location, State, Country)