VSCode SSH (Steps & Common Issues)

Using VS Code with Linprog (Step-by-Step Walkthrough)

This guide walks you through setting up Visual Studio Code (VS Code) to work with the linprog servers using Remote-SSH. Follow the steps in order.

Step 1: Download and Install VS Code

If you do not already have VS Code installed:

1. Go to https://code.visualstudio.com
2. Download the version for your operating system (Windows, macOS, or Linux)
3. Install VS Code using the default options

Once installed, open VS Code.

Step 2: Install the Remote-SSH Extension

1. In VS Code, open the Extensions tab
   • Click the Extensions icon on the left sidebar (or press Ctrl+Shift+X)
2. Search for Remote – SSH
3. Install the extension published by Microsoft

This extension allows VS Code to connect to remote Linux servers like linprog.

Step 3: Open the Remote-SSH Configuration File

1. Click the Remote Explorer icon on the left sidebar
   • (It looks like a monitor with a small connection icon.)
2. Click the gear icon (⚙️) next to “SSH”
3. When prompted to select a configuration file, choose the first option
   • (This is usually your user-level SSH config file.)

VS Code will open your SSH configuration file in an editor tab.

Step 4: Configure a Linprog Server (Important)

In the SSH config file, add an entry like the following:

Host linprogX
    HostName linprogX.cs.fsu.edu
    User yourcsusername
    MACs hmac-sha2-256

Important rules:

• Replace yourcsusername with your actual CS username
• You must choose exactly one server: linprog1 through linprog8
• Do not use just linprog as the hostname

Why this matters:
If you do not specify a numbered server (1–8), VS Code may connect you to a different linprog server each time.
This creates multiple unused VS Code server instances, which most students forget to terminate and can cause problems later.

Pick one linprog server and always use that same host in VS Code.

Save the file when finished.

Step 5: Connect to Linprog Using VS Code

1. Open the Remote Explorer
2. Under SSH Targets, click linprog1 (or whichever number you chose)
3. VS Code will prompt for your password
4. The first connection may take a few minutes while VS Code installs required components on linprog

Once connected, VS Code will open a new window that is running directly on the linprog server.

When you are finished working, it is important to properly disconnect from the linprog server
to avoid leaving unused VS Code server instances running.

Step 6: How to Disconnect Safely

1. Open the Command Palette
   (Ctrl+Shift+P on Windows/Linux or Cmd+Shift+P on macOS)
2. Select/Search Remote: Close Remote Connection

This cleanly terminates your VS Code Remote-SSH session on the linprog server.

Do not simply put your computer to sleep or close your laptop without disconnecting,
as this may leave background VS Code processes running on linprog.

Troubleshooting Common Problems

Problem: VS Code Keeps Asking for Your Password Repeatedly

If you can SSH into linprog using Tectia, but VS Code keeps asking for your password:

1. SSH into shell.cs.fsu.edu using Tectia
2. Run the following command:

passwd

3. Reset your password
4. Try connecting again from VS Code

Problem: VS Code Suddenly Stops Connecting to Linprog

If VS Code was working before and suddenly fails to connect:

1. SSH into linprog using Tectia (Windows) or Terminal (macOS/Linux)
2. Run the following command:

mv $HOME/.vscode-server $HOME/.vscode-server-bad

3. Return to VS Code and reconnect to linprog

VS Code will reinstall its server components. This may take a few minutes.

Important Notes

• Do NOT connect VS Code to shell.cs.fsu.edu
• Always connect VS Code directly to one specific linprog server (1–8)
• Use the same linprog server every time

This avoids duplicate VS Code instances and prevents unnecessary issues.