Troubleshooting WSL

• Troubleshooting WSL 
  • The CFD extension installer fails
  • The installer seems OK, but the CFD extension does not get going, or there are errors with installing the Backend from IDA ICE
    • Is WSL active and OK?
    • Microsoft "Smart App Control" 
    • Is the backend known to WSL?
    • Does the backend have networking?
    • VPN client running?
  • I get a CFD process error when Install backend
    • • Workaround
  • I see something about SparseVHD not supported
  • Manually remove the CFD backend 

The CFD extension installer fails

• The WSL activation sequence leaves a log file in %LOCALAPPDATA%/ice-cfd/wslactivation.log. Collect this file and send it to support.
• One can try to re-install the CFD extension, but this requires the already installed program to be removed first. One workflow is to uninstall any already installed versions of the CFD extension, then reboot for good measure and re-install the CFD extension.
• If all fails, it is good practice to try to perform the activation manually, as described above, before contacting support.

The installer seems OK, but the CFD extension does not get going, or there are errors with installing the Backend from IDA ICE

Is WSL active and OK?

Run the following command and read the output text:

Normally the output contains information like, "Default Version: 2", but if WSL is not properly activated, some error message or helpful text is written. If there seems to be an error message, please try the manual installation steps outlined above before contacting support.

Microsoft "Smart App Control"

It has been noted on at least one system that the Windows security feature "Smart App Control" blocks IDA ICE from executing wsl.exe. Such an intervention is probably listed among the Windows Notifications. If this seems to occur, the simplest solution is to disable Smart App Control, if that is an option.

Is the backend known to WSL?

First check for the existence of the CFD backend. Run the command wsl -l -v and look for a line starting with equa-linux (It can be in a Stopped or Running state and still be OK):

If there is no mention of "equa-linux" in the output, then the backend is not installed.

Does the backend have networking?

One known reason for failure to commuinicate with the backend is that the WSL instance (equa-linux) is prevented to create it's network. To test if this is the case, open a powershell or a DOS command prompt and run the command:

This should return an IP address, like 172.31.109.138. If it returns nothing, there is a network setup error in WSL. Possible reasons:

• A VPN client, e.g. Cisco, is running and prevents WSL networking
  • Try to turn of the VPN client and try again.
• IT security settings.
  • Contact your IT support.

VPN client running?

As noted in the previous section, VPN clients can be set to block or re-route internal networking. This will prevent the WSL backend from being provided a network interface or that the WSL network is not reached. Try to disable the VPN client and then shutdown the WSL backend (from the session form or from a terminal with the command wsl --shutdown) and restart IDA ICE. If you have IT support at hand, they may provide help.

I get a CFD process error when Install backend

This may or may not be caused by a company firewall or proxy that does not trust the SSL-certificates from our file server when downloading from within IDA ICE.

Workaround

We will fix this error as soon as we get a bug fix release out, but for the time being:

1. Manually download the backend image file from here https://files.equa.se/delivery/cfd/prod/ubuntu-24.04-openfoam-equa-wsl-image.tar.zip
2. Copy the downloaded file (do NOT unzip) to the user folder %LOCALAPPDATA%\ice-cfd\wsl\.
3. Open IDA ICE, and in the WSL management form, select Reset backend (instead of Install backend). The Reset function is identical to the install function, apart from that it does not first attempt to download the file.

Then, to be able to run CFD you need to patch a python file in the IDA ICE installation:

1. Download the following file and unzip it (the resulting file is downloads.py, its human readable, so you may inspect contents for security reasons): downloads.zip
2. Locate the the following file in your IDA ICE installation (Installation path may vary) C:\Program Files(x86)\IDA511\bin\cfd\python\wsl\downloads.py  and replace this file with the downloads.py you just extracted.

Restart IDA ICE -> Open the CFD tab -> Select the Session... link above the right table and try "Launch session".

I see something about SparseVHD not supported

SparseVHD is an optional and experimental WSL2 feature for better management of disk space. This is enabled by the CFD installation, but is on some systems not allowed. If you get an error that seems to reference SparseVHD, then edit the .wslconfig file. It is located in your home folder (%USERPROFILE%)

In this file, remove the entire [experimental] section and restart WSL.

Manually remove the CFD backend

Removing the backend does not affect the IDA ICE CFD extension installation. The backend can be freshly installed again from IDA ICE as described in the installation instructions.

Complete removal of the CFD backend can be done in the WSL management form in IDA ICE. But it can also be done manually as follows:

(For later CFD extension versions, the wsl image name may contain a version suffix, like equa-linux-v51 or equa-linux-v52, et c.)