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Incident affecting access to hku.hk websites from outside HKU network

1. Incident affecting access to hku.hk websites from outside HKU network
2. Recommended rectifications
3. Workarounds for immediate access to .hku.hk websites

**Announcement related to Course Enrollment Exercise** (sent 10 August 2016)
Appendix 1: The correct MX records for hku.hk

1. Incident affecting access to hku.hk websites from outside HKU network

University members may have problem in gaining access to hkuportal.hku.hk and www.hku.hk via some Network Service Providers (NSPs) outside HKU campus.  This was observed late afternoon yesterday (August 9, 2016) and it was found to be corruption of the Domain Name Service (DNS) data in some NSPs due to a system setting error on HKU side.  The error has been rectified last night, but the problem triggered continues to exist as the correct IP addresses of the affected HKU domain names take time to propagate throughout the Internet.  In effect, some users’ browsers may not be able to correctly visit certain HKU websites, including www.hku.hk and hkuportal.hku.hk, from outside HKU campus, while others may find these websites functioning normally, depending on what NSP the users are using.

As a temporary measure, please access the following websites until the DNS records are cleared by the affected Network Service Providers-

- www.hku.hk (use http://www.hku.edu.hk OR http://www.hku.edu OR

- webmail.hku.hk (use https://webmail.hku.edu.hk/ OR https://webmail.hku.edu/ OR, and then accept certificate warning)

- hkucc1.hku.hk (use https://hkucc1.hku.edu.hk/ OR https://hkucc1.hku.edu/, OR and then accept certificate warning)

2. Recommended rectifications

a. Change DNS server

** Before changing the DNS server setting, please take a picture of your existing DNS record in case you wish to revert the DNS record in future.**

Please refer to following procedures to change DNS server settings on your device:

If resetting the DNS can't resolve the connection problem, please also try the following steps:

b. Restart broadband router/modem

Please power off and restart the broadband router/modem being in use at home or other off-campus locations which have problems in accessing the hku.hk websites.

c. Flush DNS record at users’ computer

Users are recommended to try the following steps to flush the DNS records at their Windows/Mac PCs:

Mobile device users

Please power off and restart your mobile devices to flush the DNS record.

Windows users

Click START -> find or type 'cmd'.  Then type ipconfig /flushdns.

Macintosh users

Please refer to the following instruction on flushing the DNS records based on the version of Mac OS being used-

OSX 10.11.0

sudo killall -HUP mDNSResponder

OSX 10.10.4

sudo killall -HUP mDNSResponder

OSX 10.10.0 – 10.10.3

sudo discoveryutil mdnsflushcache

OSX 10.9  – 10.8 – 10.7

sudo killall -HUP mDNSResponder

OSX 10.5 – 10.6

sudo dscacheutil -flushcache

d. Clear the web-browser cached data

  • Edge

i. Click the Hub icon hub icon.

ii. Click the History icon history.

iii. Click the link labeled Clear all history.

iv. Check the boxes for each item you want to clear.

v. Click the Clear button. The message "All Clear!" will appear at the top when the data has been erased.

  • Internet Explorer

i. Go to Tools.

ii. In General tab, go to Browsing history. Click Delete button.

iii. Check "Temporary Internet files and websites files", "Cookies and website data" and "History" and click Delete button.

iv. Click Apply and then click OK.

  • Chrome

i. Open Chrome.

ii. On your browser toolbar, click the Chrome menu Menu. Then choose Settings.

iii. Go to Privacy, click Clear browsing data....

iv. Check "Cookies and other site and plug-in data" and "Cached images and files."

v. Click Clear browsing data.

  • Firefox

i. Click the menu button New Fx Menu and choose Options.

ii. Select the Advanced panel.

iii. Click on the Network tab.

iv. In the Cached Web Content section, click Clear Now.

v. Close the about:preferences page. Any changes you've made will automatically be saved.

  • Safari

i. Open Safari.

ii. Click Preferences. Choose Advanced tab.

iii. At the bottom, check "Show Develop menu in menu bar".

iv. Then go up to Develop. Choose Empty Caches.

3. Workarounds for immediate access to .hku.hk websites

In case the above rectifications do not work and you have immediate need to access some .hku.hk websites, for example, for course selection or master registration, please consider the following workarounds-

  1. Please return to the campus with your notebook PC.  Connection to .hku.hk websites on campus is NOT affected by this incident.  In case any problem is encountered, please bring your notebook to our Service Desk on 1/F, Library Building (Old Wing).
  2. Connect to HKU network via HKU Virtual Private Network (HKUVPN) after one-time registration to use 2-factor authentication (2FA) and configuration.  The 2FA registration, HKUVPN configuration and connection procedures are available at 


    In case your connection fails after successful 2FA registration and configuration, please update the parameter "vpn2fa.hku.hk" used in the configuration procedures by "vpn2fa.hku.edu.hk".

    ** IMPORTANT: After configuration, please try to establish a connection using HKUVPN to make sure your configuration is done properly and can connect to the campus network without problem.  For new students, please arrange the 2FA registration AFTER you change your HKU Portal UID (i.e. HKU email address). 

**Announcement related to Course Enrollment Exercise** (sent 10 August 2016)

Serious problems for gaining access to HKU Portal by users of some Network Service Providers (NSPs) outside HKU campus was observed late afternoon yesterday.  The error has been rectified last night, but the problem triggered continues to exist.  As this will have impact on first-come-first-served courses, today’s (August 10) course enrollment exercise for all current undergraduate students will therefore be postponed until next Monday, August 15, 2016.

The revised schedule is as follows:


Year 4 (or above) students

Year 3 students

Year 2 students

Course Selection Period starts

Aug 15, 2016 (Mon)


Aug 15, 2016 (Mon)


Aug 15, 2016  (Mon)


Suspension Period (submission of enrollment requests is not allowed)

Aug 16, 2016 (Tue)


Course Selection Period ends

Aug 19, 2016 (Fri)


You are highly recommended to declare your major/minor and perform other course planning activities as necessary before August 15, 2016 so that you can perform course selection during the course selection period starting August 15, 2016 accordingly.

Appendix 1: The correct MX records for hku.hk

The correct MX records for hku.hk should be:



IP Address