🛠️ Fix: "Failed to Connect to Server" When Opening a VM Console (noVNC)

When you open a VM from the ggRock admin panel, such as ToolchainVM or an image VM, the noVNC screen shows a red banner reading "Failed to connect to server", and the console never loads.

📌 Who This Affects

Servers updated to Debian 12 or Debian 13 that are running a recent version of ggRock.

🔎 What Causes It

The console connects through a WebSocket path that changed from /websockify to /vnc/websockify. On affected servers, the new path is handled by an nginx rule that doesn't pass the WebSocket headers, so the connection fails. The fix adds a matching rule for the new path.

✅ Step 1: Run the Fix

Open the Debian Control Panel terminal, SSH, or the server console as root, and run:

wget -O - https://images.ggleap.com/ManagedServices/Scripts/fix-novnc-websockify.sh | bash -

The script:

• Backs up /etc/nginx/conf.d/ggrock.conf with a timestamp
• Adds the new rule, copied from the working /websockify rule
• Tests the nginx configuration before applying it
• Restores the backup automatically if the test fails

When it succeeds, it prints:

OK: /vnc/websockify block in place; nginx tested and reloaded.

Want to read the script first? Download it and run it yourself:

wget https://images.ggleap.com/ManagedServices/Scripts/fix-novnc-websockify.sh
less fix-novnc-websockify.sh
bash fix-novnc-websockify.sh

🧪 Step 2: Test the Console

1. Refresh the ggRock admin panel.
2. Open the VM and click Connect in the noVNC window.
3. The VM's screen should appear.

🔁 If the Script Says a Block Already Exists

If someone added a /vnc/websockify rule by hand, the script shows it and makes no changes. Those rules are sometimes missing headers or use a short timeout. To replace it with the correct rule, run:

wget -O - https://images.ggleap.com/ManagedServices/Scripts/fix-novnc-websockify.sh | REPLACE=1 bash -

↩️ Undo the Fix

The script prints a rollback command at the end. It looks like this, with your own backup file name:

cp -a /etc/nginx/conf.d/ggrock.conf.bak.YYYYMMDD-HHMMSS /etc/nginx/conf.d/ggrock.conf && systemctl reload nginx

⚠️ Troubleshooting

🧰 Workaround

You can still control VMs from the Debian Control Panel. See Using Cockpit Virtual Machines on ggRock (Advanced).

🆘 Still Stuck?

Chat with our support team with the purple chat bubble at the bottom-right of ggcircuit.com and include:

• A screenshot of the error
• Your ggRock version (shown at the bottom-left of the admin panel)
• Your Debian version