code-server/docs/guide.md

Setup Guide

• 1. Acquire a remote machine
  • Requirements
  • Google Cloud
• 2. Install code-server
• 3. Expose code-server
  • SSH forwarding
  • Let's Encrypt
    • NGINX
  • Self Signed Certificate
  • Change the password?
  • How do I securely access development web services?

This guide demonstrates how to setup and use code-server. To reiterate, code-server lets you run VS Code on a remote server and then access it via a browser.

Further docs are at:

• README for a general overview
• INSTALL for installation
• FAQ for common questions.
• CONTRIBUTING for development docs

We highly recommend reading the FAQ on the Differences compared to VS Code before beginning.

We'll walk you through acquiring a remote machine to run code-server on and then exposing code-server so you can securely access it.

1. Acquire a remote machine

First, you need a machine to run code-server on. You can use a physical machine you have lying around or use a VM on GCP/AWS.

Requirements

For a good experience, we recommend at least:

• 1 GB of RAM
• 2 cores

You can use whatever linux distribution floats your boat but in this guide we assume Debian on Google Cloud.

In order to work properly, your environment should have WebSockets enabled, which code-server uses to communicate between the browser and server

Google Cloud

For demonstration purposes, this guide assumes you're using a VM on GCP but you should be able to easily use any machine or VM provider.

You can sign up at https://console.cloud.google.com/getting-started. You'll get a 12 month $300 free trial.

Once you've signed up and created a GCP project, create a new Compute Engine VM Instance.

1. Navigate to Compute Engine -> VM Instances on the sidebar.
2. Now click Create Instance to create a new instance.
3. Name it whatever you want.
4. Choose the region closest to you based on gcping.com.
5. Any zone is fine.
6. We'd recommend a E2 series instance from the General-purpose family.
   • Change the type to custom and set at least 2 cores and 2 GB of ram.
   • Add more vCPUs and memory as you prefer, you can edit after creating the instance as well.
   • https://cloud.google.com/compute/docs/machine-types#general_purpose
7. We highly recommend switching the persistent disk to an SSD of at least 32 GB.
   • Click Change under Boot Disk and change the type to SSD Persistent Disk and the size to 32.
   • You can always grow your disk later.
8. Navigate to Networking -> Network interfaces and edit the existing interface to use a static external IP.
   • Click done to save network interface changes.
9. If you do not have a project wide SSH key, navigate to Security -> SSH Keys and add your public key there.
10. Click create!

Remember, you can shutdown your server when not in use to lower costs.

We highly recommend learning to use the gcloud cli to avoid the slow dashboard.

2. Install code-server

We have a script to install code-server for Linux, macOS and FreeBSD.

It tries to use the system package manager if possible.

First run to print out the install process:

curl -fsSL https://code-server.dev/install.sh | sh -s -- --dry-run

Now to actually install:

curl -fsSL https://code-server.dev/install.sh | sh

The install script will print out how to run and start using code-server.

Docs on the install script, manual installation and docker image are at ./install.md.

3. Expose code-server

Never, ever expose code-server directly to the internet without some form of authentication and encryption as someone can completely takeover your machine with the terminal.

By default, code-server will enable password authentication which will require you to copy the password from thecode-serverconfig file to login. It will listen onlocalhost to avoid exposing itself to the world. This is fine for testing but will not work if you want to access code-server from a different machine.

There are several approaches to securely operating and exposing code-server.

tip: You can list the full set of code-server options with code-server --help

SSH forwarding

We highly recommend this approach for not requiring any additional setup, you just need an SSH server on your remote machine. The downside is you won't be able to access code-server on any machine without an SSH client like on iPad. If that's important to you, skip to Let's Encrypt.

First, ssh into your instance and edit your code-server config file to disable password authentication.

# Replaces "auth: password" with "auth: none" in the code-server config.
sed -i.bak 's/auth: password/auth: none/' ~/.config/code-server/config.yaml

Restart code-server with (assuming you followed the guide):

sudo systemctl restart code-server@$USER

Now forward local port 8080 to 127.0.0.1:8080 on the remote instance by running the following command on your local machine.

Recommended reading: https://help.ubuntu.com/community/SSH/OpenSSH/PortForwarding.

# -N disables executing a remote shell
ssh -N -L 8080:127.0.0.1:8080 [user]@<instance-ip>

Now if you access http://127.0.0.1:8080 locally, you should see code-server!

If you want to make the SSH port forwarding persistent we recommend using mutagen.

# Same as the above SSH command but runs in the background continuously.
# Add `mutagen daemon start` to your ~/.bashrc to start the mutagen daemon when you open a shell.
mutagen forward create --name=code-server tcp:127.0.0.1:8080 <instance-ip>:tcp:127.0.0.1:8080

We also recommend adding the following lines to your ~/.ssh/config to quickly detect bricked SSH connections:

Host *
ServerAliveInterval 5
ExitOnForwardFailure yes

You can also forward your SSH and GPG agent to the instance to securely access GitHub and sign commits without copying your keys.

1. https://developer.github.com/v3/guides/using-ssh-agent-forwarding/
2. https://wiki.gnupg.org/AgentForwarding

Let's Encrypt

Let's Encrypt is a great option if you want to access code-server on an iPad or do not want to use SSH forwarding. This does require that the remote machine be exposed to the internet.

Assuming you have been following the guide, edit your instance and checkmark the allow HTTP/HTTPS traffic options.

1. You'll need to buy a domain name. We recommend Google Domains.
2. Add an A record to your domain with your instance's IP.
3. Install Caddy https://caddyserver.com/docs/download#debian-ubuntu-raspbian.

sudo apt install -y debian-keyring debian-archive-keyring apt-transport-https
curl -1sLf 'https://dl.cloudsmith.io/public/caddy/stable/cfg/gpg/gpg.155B6D79CA56EA34.key' | sudo apt-key add -
curl -1sLf 'https://dl.cloudsmith.io/public/caddy/stable/cfg/setup/config.deb.txt?distro=debian&version=any-version' | sudo tee -a /etc/apt/sources.list.d/caddy-stable.list
sudo apt update
sudo apt install caddy

4. Replace /etc/caddy/Caddyfile with sudo to look like this:

mydomain.com

reverse_proxy 127.0.0.1:8080

If you want to serve code-server from a sub-path, below is sample configuration for Caddy:

mydomain.com/code/* {
  uri strip_prefix /code
  reverse_proxy 127.0.0.1:8080
}

Remember to replace mydomain.com with your domain name!

5. Reload Caddy with:

sudo systemctl reload caddy

Visit https://<your-domain-name> to access code-server. Congratulations!

In a future release we plan to integrate Let's Encrypt directly with code-server to avoid the dependency on Caddy.

NGINX

If you prefer to use NGINX instead of Caddy then please follow steps 1-2 above and then:

3. Install nginx:

sudo apt update
sudo apt install -y nginx certbot python3-certbot-nginx

4. Put the following config into /etc/nginx/sites-available/code-server with sudo:

server {
    listen 80;
    listen [::]:80;
    server_name mydomain.com;

    location / {
      proxy_pass http://localhost:8080/;
      proxy_set_header Host $host;
      proxy_set_header Upgrade $http_upgrade;
      proxy_set_header Connection upgrade;
      proxy_set_header Accept-Encoding gzip;
    }
}

Remember to replace mydomain.com with your domain name!

5. Enable the config:

sudo ln -s ../sites-available/code-server /etc/nginx/sites-enabled/code-server
sudo certbot --non-interactive --redirect --agree-tos --nginx -d mydomain.com -m me@example.com

Make sure to substitute me@example.com with your actual email.

Visit https://<your-domain-name> to access code-server. Congratulations!

Note: if you set proxy_set_header Host $host; in your reverse proxy config, it will change the address displayed in the green section of code-server in the bottom left to show the correct address.

Self Signed Certificate

note: Self signed certificates do not work with iPad normally. See ./ipad.md for details.

Recommended reading: https://security.stackexchange.com/a/8112.

We recommend this as a last resort because self signed certificates do not work with iPads and can cause other bizarre issues. Not to mention all the warnings when you access code-server. Only use this if:

1. You do not want to buy a domain or you cannot expose the remote machine to the internet.
2. You do not want to use SSH forwarding.

ssh into your instance and edit your code-server config file to use a randomly generated self signed certificate:

# Replaces "cert: false" with "cert: true" in the code-server config.
sed -i.bak 's/cert: false/cert: true/' ~/.config/code-server/config.yaml
# Replaces "bind-addr: 127.0.0.1:8080" with "bind-addr: 0.0.0.0:443" in the code-server config.
sed -i.bak 's/bind-addr: 127.0.0.1:8080/bind-addr: 0.0.0.0:443/' ~/.config/code-server/config.yaml
# Allows code-server to listen on port 443.
sudo setcap cap_net_bind_service=+ep /usr/lib/code-server/lib/node

Assuming you have been following the guide, restart code-server with:

sudo systemctl restart code-server@$USER

Edit your instance and checkmark the allow HTTPS traffic option.

Visit https://<your-instance-ip> to access code-server. You'll get a warning when accessing but if you click through you should be good.

To avoid the warnings, you can use mkcert to create a self signed certificate trusted by your OS and then pass it into code-server via the cert and cert-key config fields.

Change the password?

Edit the password field in the code-server config file at ~/.config/code-server/config.yaml and then restart code-server with:

sudo systemctl restart code-server@$USER

Alternatively, you can specify the SHA-256 of your password at the hashed-password field in the config file. The hashed-password field takes precedence over password.

How do I securely access development web services?

If you're working on a web service and want to access it locally, code-server can proxy it for you.

See the FAQ.