Windows shown as “No internet” when it can access internet

Windows is running DNS and HTTP test against  to check if it has internet connection or not. So if your internet can’t access this website, for example, in China, sometimes this domain is hijacking by GFW, then windows will show as no internet connect.

A quick fix is to disable Active Probe via modify registry.

Change below value from 1 to 0 to disable Active Probe

HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\NlaSvc\Parameters\Internet 的 EnableActiveProbing 

Upgrade to Windows 10 20H1 (2004) BSOD

Today when I tried to upgrade my windows 10 1909 to windows 10 20H1, I got multiple BSOD.
Based on the information on the BSOD screen, the BSOD were caused by some drivers (aksdf.sys, hardlock.sys, aksfridge.sys)

bsod 1

bsod 2)

After investigation, looks like all these drivers were Sentinel Data Filter Device Driver/Aladdin HASP Data Filter Device Driver, Which provided by Safenet.
I have no idea how these driver got installed into my computer, and I can’t remove them from control panel.

The fix is to download the Sentinel HASP/LDK Windows GUI Run-time Sentinel HASP/LDK Windows GUI Run-time from thalesgroup website

Install, then uninstall it, reboot.

After reboot, I can upgrade to windows 10 20H1 successfully.

Install certificate for Unifi Controller

1. Request certificate. I saved my certificate as unifi2020.crt and unifi2020.key
2. Replace certificate on unifi controller

3. Restart unifi

Fix ‘No space left on device’ when install vsphere 6.7u3

Add Cloudflare Dynamic DNS Support on Unifi USG

It seems Unifi USG still doesn’t support Cloudflare Dynamic DNS, even though lots of users voted for this feature.
In the past I’m using dnsomatic to update cloudflare DDNS, but dnsomatic is not working anymore. So I spent sometime to find a solution.

1. Create a config.gateway.json and put it on unifi controller. Then provision USG.
If you don’t know how to create the file, please refer to

2. Upgrade ddclient on USG to version 3.9.0.
Save below script as a bash file:

And chomod +x the file and run it with root. Then the script will install libdata-validate-ip-perl as well as ddclient 3.9.0.

3. As we are using standard ddclient, so we have to create a copy of the old ddclient configuration file.

4. Then restart ddclient.

5. Done. From system log, you should be able to see ddclient update cloudflare DDNS now.

fix “[Error28] No space left on device” when upgrade ESXi to 6.7 U2

To upgrade ESXi to 6.7U2, usually use below command is enough:

But this time I got error “[Error28] No space left on device”.

Someone said to enable the swap on SSD can fix the issue, but I tried, it doesn’t work.

The fix is to manually update a vib first

Then run the update again, you should be able to update your ESXi host now.