Cisco IP phone upgrade

The HKU Cisco IP phone system server was first set up in 2012, and it will reach its end-of-support in July 2017.  To ensure reliable operation of the IP phones of the University, a major upgrade of the system (from Cisco Unified Communication Manager version 8.6 to 11.5) is now in progress. The upgrade involves all Cisco IP phones of the University (phone numbers start with 3917) and the upgrading work is expected to complete in July 2017.  

We plan the upgrade process in a way that will lead to least impact to our users.  Since some interruptions to the IP phone service would be triggered in the course of the system upgrade, IP phone users are required to pay attention to the followings:

  1. DO NOT unplug any phones from the network from June 30, 2017 until July 10, 2017. Otherwise, the phones will fail to work after the system upgrade.
  2. All configuration changes, including the features (e.g. simultaneous ringing) that have been turned on or off by the users, will not be allowed from June 30, 2017 until July 10, 2017 when the upgrade is complete. Any changes made during the above “no-updating” period will not be effective after the upgrade (except the “call forwarding” settings as will be explained in (3) below).
  3. After the upgrade is completed, ITS will re-configure all phones with the “call forwarding” settings changes made by users during the “no-updating” period manually.  Therefore, we would request our users to check the correctness of their call forwarding settings after the upgrade.
  4. Phone call and voicemail services of the IP phones with “3917” as the leading number will be suspended from 11:00pm on July 8, 2017 (Saturday).  The phone call service is expected to resume before noon on July 9, 2017 (Sunday). 
  5. All messages in the voicemail system will be marked as NEW and unattended after the upgrade and the message indicator (the red LED on the handset) will be turned on, regardless of whether they have been listened or not. Hence, users are recommended to delete all listened messages in their voicemail boxes before July 7, 2017.  Please refer to the following useful information when it is needed.
    User guide on Cisco voicemail system can be found at
    To reset voicemail PIN, please submit CF78a.
  6. After the upgrade, self-signed SSL certificates will be used by the Cisco unified CM ( temporarily until the trusted certificates are ready. Please accept the self-signed certificates when prompted on your computer.
  7. Some phones may hang during the upgrade process. The users of such a phone can reset it by unplugging the network cable to the phone and plug it back again. Please contact ITS Service Desk at 39170123 or in case that the procedure could not resolve the problem.
  8. Under the rare case that your phone failed to migrate to the new IP phone cluster, please report the case to ITS Service Desk or for assistance.

For any further question, please feel free to contact the undersigned or our Service Desk at 3917 0123 or


Kenneth Yip
Unified Communication Team
Tel: 39177973