Articles on: ggRock

🛠️ 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

If the error returns after an update, run the fix again

🧪 Step 2: Test the Console

Refresh the ggRock admin panel.
Open the VM and click Connect in the noVNC window.
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

Message	What it means
`run as root`	Run the command as root or with `sudo`.
`config not found`	`/etc/nginx/conf.d/ggrock.conf` doesn't exist on this server. Contact support.
`no 'location /websockify' block found`	The config doesn't look like a standard ggRock install. Contact support.
`nginx -t FAILED - reverting`	The script restored your original config. Contact support with a copy of the output.

🧰 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

Updated on: 24/10/2026

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