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automated - Run commands remotely

This automation framework will enable you to run commands (including locally defined Bash functions) remotely.

Demo

Features

  • SUDO support

    Use the -s argument to run a command on remote targets as SUDO root.

  • Simple, yet powerful API

    Commands running via automated.sh have access to all functions defined in libautomated.sh.

  • Running functions from local libraries remotely

    Load any number of extra files with the -l argument.

  • STDIN, STDOUT and STDERR are transparently attached to the remotely running command

    Yes, you can do this:

    # Save ping output both on target.example.com and local controlling workstation
    ping -c10 www.google.com | automated.sh -s --stdin -c 'tee /tmp/test.txt' target.example.com | tee /tmp/test.txt

    and this:

    echo "I have travelled over the remote target back to the STDOUT on the controlling workstation" | automated.sh --stdin -c 'echo "Look, I am on STDERR" >&2; cat' target.example.com
  • Exit code of the remote command is retained

    The following will output 5:

    automated.sh -c 'exit 5' target.example.com; echo $?
  • Macro support

    You can use macros to run dynamically generated code. Commands specified with the -m argument are evaluated locally and the output is executed remotely. The following is an example for unlocking the remote encrypted LUKS volumes on multiple remote machines using individual passwords for every target from local pass store:

    automated.sh -m 'printf "%s\n" "PASSPHRASE=$(pass "LUKS/${target}")"' -c 'cryptsetup luksOpen --key-file <(printf "%s" "$PASSPHRASE") /dev/vg0/encrypted decrypted' target1.example.com target2.example.com
  • Commands can be run in remote terminal multiplexer session

    Safe OS updates over flaky SSH connections:

    # Simply repeat this command if the SSH connection drops and you will be
    # re-attached to the existing session
    automated.sh -s -c 'run_in_multiplexer "yum -y update; exit"' centos.test

    Take a look at the OS script from the ops-scripts repository for an extended version of this example.

  • File upload support

    Use --cp or --cp-list arguments to copy files from the controlling workstation to the remote targets. Use --drag argument and drop() function if you want to calculate destination filename during runtime on every target individually. The following example uses facts to decide decide where to put the certificate:

    automated.sh --drag CA.crt ca_cert_file -c 'drop ca_cert_file "${FACT_PKI_CERTS}/CA.crt"' target.example.com
  • Zero remote footprint

    Nothing is written on the remote targets unless you do that explicitly. All commands are executed on the fly, no temporary files are created.

  • Minimal number of dependencies

    SUDO functionality and some API functions depend on Python 2.7 or later (including 3.x).

  • Local mode

    Specify --local as a target to run commands directly on local system, bypassing the SSH. For example:

    automated.sh -s -c 'id' --local

Use cases

  • Deployment of various agents, like Puppet Agent, CollectD or Beats
  • Deployment of applications
  • Configuration management
  • Delivery and remote decryption of SSL certificates
  • OS updates
  • Automation of ad hoc tasks executed on multiple systems

See the cookbook directory and the ops-scripts repository for some examples.

Foundation for your automation scripts

You can use automated.sh as the framework for your own automation scripts

my_script.sh:

#!/usr/bin/env bash

set -euo pipefail

# This block will execute when this script is run directly, not sourced
# or piped into an interpreter
if ! (return 2> /dev/null); then

    # source libautomated.sh so we can use the quoted() function locally.
    source automated-config.sh
    source "${AUTOMATED_LIBDIR%/}/libautomated.sh"

    exec automated.sh \
         -s \
         -m 'printf "%s\n" "ADMIN=$(quoted "$(whoami)@$(uname -n)")"' \
         -c main \
         -l "${BASH_SOURCE[0]}" \
         "${@}"

fi

print_message () {
    echo "Hello World from $(whoami)@$(uname -n). ${ADMIN} controls me" | colorized 94
}

main () {
  print_message
}

Using:

my_script.sh centos.test ubuntu.test fedora.test freebsd.test

Supported systems

Any *NIX system with Bash version 4 or later should work. SUDO PTY handling and file descriptor magic on targets is done by the helper Python script.

The following systems were confirmed to work both as controlling workstation and remote targets

  • CentOS 7+
  • Ubuntu 16.04+
  • Fedora
  • FreeBSD 11+

Installing

From source

sudo make install

Testing

Unit-tests

Run make test.

End-to-end tests

Prerequisites:

  • Podman
  1. Create the test environment:

    • make SSHD_TARGET_OS=centos7 sshd-target
    • make app-env

    First step creates a sshd container with a pre-configured test user. Supported values for SSHD_TARGET_OS are centos7, centos8, fedora34, and ubuntu2104. Second step creates a container with the ssh command overriden (see e2e/ssh) to enable access the sshd target and a working copy Automated installed. You need to run make app-env-down app-env each time you modify the Automated code to update the app env container with the new changes.

  2. Run make e2e-test to run the functional tests inside the created containers. Due to some issues with STDIN handling in Podman you might get an occassional Error: read unixpacket @->/proc/self/fd/17/attach: read: connection reset by peer error.

  3. Run make app-env-down sshd-target-down to destroy both containers.

Vagrant

vagrant up will bring Fedora, CentOS, Ubuntu and FreeBSD VMs with the pre-installed automated.sh and the pre-configured user account user. The password for this user is secret. Every machine will allow passwordless SSH pubkey-based login and SUDO using this user account.

Example:

vagrant up

vagrant ssh fedora
sudo -u user -i

automated.sh -c 'uname -a' centos.test ubuntu.test freebsd.test fedora.test

exit

vagrant ssh freebsd
sudo -u user -i

automated.sh -c 'uname -a' centos.test ubuntu.test freebsd.test fedora.test