About

Do This On That (dtot) sequentially runs plain shell commands on one or more hosts in the specified order. You need SSH public key authentication already setup on the target hosts. You can run a single command across multiple hosts by running dtot from the command line with arguments, or you can feed dtot a list of commands and hosts by using some helper files. See the Usage section below for more information.

Usage

gem install dtot
dtot --help

Specify commands followed by multiple hosts to run commands, sequentially, on all hosts in specified order. Uses the currently logged in, local user as the username on the target systems.

dtot -c uptime,w,"ls -lah /" -w host1,host2,host3
dtot -c "sudo yum update -y" -w host1,host2

Or, use "do this" and "on that" files:
dtot -d do_this -o on_that

do_this

Each command should be on one line; commands are run sequentially, not in parallel (by design). See the example do_this in the examples directory of this repository.

on_that

On each line put the username with access followed by a space and then the hostname. You should have public key authentication already setup on the host for the user specified. See the example on_that in the examples directory of this repository.

Docker

First, retrieve the image from Docker Hub:

docker pull irlrobot/dtot

Next, create your do_this and on_that files in a directory on your local machine. I typically just use ~/Desktop on my Mac.

Finally, run the below from the directory where your do_this and on_that files are located:

docker run --rm \
    -v ~/.ssh/id_rsa:/root/.ssh/id_rsa \
    -v ~/.ssh/id_rsa.pub:/root/.ssh/id_rsa.pub \
    -v ~/Desktop/do_this:/dtot/commands \
    -v ~/Desktop/on_that:/dtot/hosts \
    dtot

NOTE: The Docker image currently only supports SSH keys without a passphrase.