Connect via VNC to macOS to see iOS Simulator

I’m trying to debug UI tests randomly failing, but I’m unable to login with the user “distiller” which is running Xcode and the UI tests. I’m able to connect via VNC, but since I can’t change the distiller password with the command “sudo passwd distiller” I’m unable to login.
Is there a way to find the current distiller password or to configure it in the .circleci.yml?

Hi @lm2s!

We actually have an article on this process here:

Likely you are using a version later than 10.2.0 for your Xcode image, in which case you will need to set a new user to utilize during the VNC process.

To mitigate this, you can create a new user account, and use the credentials of that new account instead of the " distiller " account for VNC login.

For example, the following command will create a user " vncuser ":

sudo /usr/sbin/sysadminctl -addUser vncuser -fullName "VNC User" -password <password> -admin

Hope that helps!

Hi @nbialostosky

Thank you for your answer, it has helped me ssh into the machine and get VNC viewer running. However, it is the user distiller which is launching the simulator to execute the tests. Was wondering if there was any way we could log into distiller or change the account password using ‘vncuser’ so we can get into it. Thanks!

Hi @mustafa10,

You’re welcome and glad that helped at least with the SSH session.

Unfortunately, there isn’t a way to log into distiller or change the account password. For security purposes with the most recent (really since about our Xcode 10.2.0 image) that user requires the existing password which is not something we are able to provide.


That’s a shame @nbialostosky ! So there is no way to actually see the iOS simulator in real-time whilst it is running tests on ‘distiller’?


Hi @mustafa10 ,

Currently there is not, as Secure Token prevents changing the password and that is something currently enabled on our images.

With that said, you can post a feature request to have that removed from our MacOS images and it is something our team will consider in future development: