Avsh

avsh ("Augmented Vagrant sSH") is a standalone script that can be used in place of vagrant ssh. It provides greatly increased performance and several extra features.

This project is unmaintained since I no longer use Vagrant, but I'll accept PRs.

• SSH multiplexing avsh automatically establishes an SSH control socket the first time it's run, which speeds up all subsequent connections by over an order of magnitude.

  $ time vagrant ssh -c 'hostname'
  vagrant-ubuntu-trusty-64
  Connection to 127.0.0.1 closed.
  
  real    0m2.786s
  user    0m1.670s
  sys     0m0.545s
  
  $ time avsh hostname
  vagrant-ubuntu-trusty-64
  Shared connection to 127.0.0.1 closed.
  
  real    0m0.087s
  user    0m0.034s
  sys     0m0.013s

• Automatic synced folder switching avsh detects when you're working in a synced folder, and automatically switches to the corresponding directory on the guest before executing commands or starting a login shell.

  # config.vm.synced_folder '/home/masonm/asci/, '/var/www/jci',
  
  $ pwd
  /home/masonm/asci/content
  
  $ avsh pwd
  /var/www/jci/content

• Run commands on multiple machines If you have a multi-machine setup, you can use avsh -m to run a command on multiple machines.

  $ avsh -m 'openbsd,debian' uname
  OpenBSD
  Linux
  
  $ avsh -m '/(free|open)bsd/' uname
  OpenBSD
  FreeBSD

Caveats

avsh makes a number of assumptions and shortcuts in order to achieve its performance goals, so it might not work (or be appropriate) for your setup.

• Vagrantfiles are evaluated inside a fake Vagrant environment, which may cause issues with complex Vagrantfiles that use the non-DSL parts of Vagrant. Specifically, the Vagrant.has_plugin? method always returns true, and other methods on the Vagrant module are stubbed out.
• The host must be Linux with OpenSSH 5.6+ or OS X 10.7+. It'll probably work on other Unices, but hasn't been tested.
• No merging of multiple Vagrantfiles.

Installation

Download the latest release and put it in your PATH, or run the following to put it in /usr/local/bin/:

curl -sL https://github.com/MasonM/avsh/releases/download/0.1.0/avsh \
  | sudo tee /usr/local/bin/avsh > /dev/null \
    && sudo chmod ugo+rx /usr/local/bin/avsh

avsh uses the same logic as Vagrant to find your Vagrantfile. If you only use a single Vagrantfile, add export VAGRANT_CWD="/vagrantfile_dir/" to your .bashrc or .zshrc to ensure avsh and Vagrant can always find it.

Usage

Usage: avsh [options] [--] COMMAND    execute given command via SSH
   or: avsh [options]                 start a login shell

Options:
    -m, --machine MACHINE            Target Vagrant machine(s).
                                     Can be specified as a plain string for a single machine, a
                                     comma-separated list for multiple machines, or a regular
                                     expression in the form /search/ for one or more machines.
                                     If not given, will infer from the Vagrantfile.
    -r, --reconnect                  Closes SSH multiplex socket if present and re-initializes it
    -s, --ssh-options OPTS           Additional options to pass to SSH, e.g. "-a -6"
    -d, --debug                      Verbosely print debugging info to STDOUT
    -v, --version                    Display version
    -h, --help                       Display help
    -c, --command COMMAND            Command to execute (only for compatibility with Vagrant SSH)

Multi-Machine Environments

If the -m flag is not given for a multi-machine environment, avsh will try to infer the machine to connect to using the synced folders defined in your Vagrantfile. It does this by matching the current working directory against each machine in the order they are defined, using the first machine that has a matching synced folder (taking into account ancestor directories). If none are found to match, it will use the primary machine if one exists, else it falls back to the first defined machine.

When executing a command on multiple machines, automatic synced folder switching is disabled, since that can lead to hard-to-predict behavior. Additionally, a pseudo-TTY will not be allocated (i.e. SSH will not be passed the '-t' flag).