Table of Contents

• Tutorial
• Local invocation of scripts
• Run scripts inside a local container
• Run scripts remote via SSH
• Install podman to remote Ubuntu 20.04 host

## Tutorial

In the Git source tree, the TUTORIAL directory inside README.d contains a hierarchy that persistently enables IP forwarding through sysctl upon the remote SSH host named avocado

First you have to setup SSH public-key authentication for a remote host with hostname avocado.

Once that is done, you can proceed with the example:

cd TUTORIAL
rr avocado sysctl:apply

### Steps that rr performs

1. Copies .files-avocado/ to avocado:/
2. Generates the script:

#!/bin/sh
unset IFS
set -efu
PATH=/bin:/sbin:/usr/bin:/usr/sbin
LC_ALL=C
sysctl --system

3. Runs the script on host avocado via SSH.

## Local invocation of scripts

Run locally, the default without a hostname or container PID specified.
Requires tar(1) for .files
The following are equivalent:

rr namespace:script

rr localhost namespace:script

## Run scripts inside a local container

NOTE: Linux only

Run on a local container’s PID via nsenter(1). Requires tar(1) for .files.

rr 1333 namespace:script

## Run scripts remote via SSH

rr remotehost namespace:script

If a file named .ssh/config is in the current directory then that is used as the SSH config instead of the default ~/.ssh/config.

## Install cri-tools to remote Ubuntu host

$ mkdir -p examples/install-critools
$ cat > examples/install-critools/script <<-'EXAMPLE'
. /etc/os-release
echo "deb https://download.opensuse.org/repositories/devel:/kubic:/libcontainers:/stable/xUbuntu_${VERSION_ID}/ /" | tee /etc/apt/sources.list.d/devel:kubic:libcontainers:stable.list
curl -L "https://download.opensuse.org/repositories/devel:/kubic:/libcontainers:/stable/xUbuntu_${VERSION_ID}/Release.key" | apt-key add -
apt-get update
apt-get -y install cri-tools
EXAMPLE
$ cat .ssh/config
Host remotemost
Hostname 203.0.113.1
User root
$ rr remotehost example:install-critools
...
...