Thanks to visit codestin.com
Credit goes to mux.coder.com

Skip to main content
mux can run workspaces on a remote host over SSH. When configured, tool operations (file reads/edits, bash, etc.) execute on the remote machine.

​
Threat model

mux treats the remote host as potentially hostile. By default it does not forward your local keys or credentials. The only data synced to the remote machine is:

​
Why use SSH runtime

  • Security: Prompt injection risk is contained to the credentials/files on the remote machine.
  • Performance: Run many agents in parallel without burning laptop CPU/battery.
ssh workspaces

​
Host value

The host field accepts anything you can pass to ssh <host>:
  • a hostname (for example my-server.com)
  • a username and hostname (for example [email protected])
  • an alias from your ~/.ssh/config (for example my-server)
mux delegates SSH configuration to your system ssh command, so advanced settings live in ~/.ssh/config. Example entry: 
Host ovh-1
  HostName 148.113.1.1
  User root

​
Authentication

mux delegates to ssh. This is an abbreviated reference of common ways ssh authenticates.

​
Local default keys

ssh checks these locations by default: 
~/.ssh/id_rsa
~/.ssh/id_ecdsa
~/.ssh/id_ecdsa_sk
~/.ssh/id_ed25519
~/.ssh/id_ed25519_sk

​
SSH agent

If you have an SSH agent running, add your key: 
ssh-add ~/.ssh/my_key_ecdsa

​
~/.ssh/config

You can also set an explicit identity file: 
Host my-server
  HostName 148.113.1.1
  User root
  IdentityFile ~/.ssh/id_rsa

​
Coder Workspaces

If you’re using Coder Workspaces, you can use an existing workspace as a mux agent host:
  1. Run coder config-ssh
  2. Use coder.<workspace-name> as your SSH host when creating a new mux workspace
This multiplexes many mux workspaces onto a single Coder workspace, which avoids per-workspace provisioning overhead.