here is my setup:

  • Windows 7 desktop
  • VMWare Workstation 14
  • Linux clients (Ubuntu 18.4, Mint 19, Centos 7)
  • Use NAT networking for client VMs
  • Corporate proxy which filters all traffic going to the web

What I was able to setup for the linux clients

  • for apt or yum, I was able to configure them to go through the proxy.
  • ex apt: /etc/apt/apt.conf

    Acquire::http::Proxy "http://DOMAIN\USER:PASSWORD@PROXY.FQDN.COM:8080";
  • That works, I can update, install, ...

What I was not able to setup

Any other network software. - Ex. browser. I configured my linux browser to the same proxy, no luck. - I downloaded the wpad.dat for my Windows host, and extracted the proxy name (and therefore IP). Tried that in the browser proxy setting, no luck. - Same thing at the system, network proxy level.

From what I have read up to now:

  • My browsers on Windows use the wpad.dat to figure out what proxy address to use. Then NTLM authentication. I confirmed that with Fiddler on Windows, I see NTLM authentication headers.
  • I do not understand how APT does not use NTLM authentication and still works ok.

What I have tried:

  • cntlm: I setup cntlm on my linux client and that did not work. cntlm was never able to connect to the proxy. I see a connection at the network level, but it always refuse my user/password. I wonder if the proxy somehow verifies if the client is in the Windows domain before accepting connections.

Other thing I tried:

  • I had the same setup on VirtualBox. Same thing, APT was ok, any other proxy was not. So it does not look like a VMWare thing, more a Linux configuration thing.

Any other ideas?
Methods I could try to collect more information from the proxy?
Do you know how to convert the APT configuration into a browser compatible configuration?
Is VM Workstation ok for this?

Thanks for any help!


I've had a similar problem recently, but I was not even able to put APT working.

I'll share my solution, so you can evaluate if it also fit your needs.

On the Windows host side, I've set up CNTLM. For the guest systems, I'm using VirtualBox and I've set up my linux VM with a host-only network - all the traffic is forced to pass through this channel only.

Then, I only needed to set up VirtualBox to use the CNTLM address as proxy (in my case: AND set up Linux to use that address as proxy as well (in my case,

Don't forget to setup noProxy as well on the Linux OS (mine was something like ::1, 127.0.0., 192.168.56.)

With this solution, my Linux VM could access everything it wanted to.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.