Single Machine Automated Configuration Management

Grainman · 01-29-2020, 02:08 AM

G'day,

I'm trying to see if I can find a simple configuration management system what would be suitable for a single host without the typical master-slave arrangement you see with tools like Puppet or Chef.

The primary use-case I'm currently seeing is a client I have who provides their app on Raspberry Pis. Updating them to the latest configuration has been a mix of, posting SD cards, sharing multi-GB SD card images online, and/or emailing custom shell scripts, all of which are somewhat painful.

I'd love to get this to the point of making the install process something like:

Install the latest Raspbian image, and then run:

Code:

$ sudo apt-get install FOO
$ git clone https://github.com/my_client/FOO_conf
$ FOO /path/to/git/clone/of/FOO_conf

And updates as something like:

Code:

$ cd /path/to/git/clone/of/FOO_conf
$ git pull
$ FOO

But I'm not aware of any tool that would work as "FOO" in that.

Does anyone know of any tool that would be suitable for something like this?

berndbausch · 01-29-2020, 09:09 PM

Your question is a bit confusing. You want configuration management on a single host, but then your client uses Raspberry Pis (plural).

If your configuration is simple, you can just ship the configuration files. But that doesn't seem to be the case here.

Thus, back to configuration management systems. Puppet and Chef have a steep learning curve and might be overkill. Ansible is simpler and works without special server software - all you need on the target system is the ssh server and Python. You still have to invest a few hours learning, but I would say it's an order of magnitude simpler than Puppet (I have no experience with Chef).

Grainman · 02-02-2020, 10:30 PM

I mean single-host in the sense that Solitaire is a single-player game; yes, lots of people play Solitaire, but they don't interact with each other while doing so.

Ansible with SSH isn't really likely to work for this unfortunately because the Pis are small devices that move around (between various countries in Africa and Europe), so there's no way to predict which ones will be turned on or connected to the internet, or what IP addresses or hostnames they will have when they are on.

Thanks for your reply anyway. I'll have to keep looking though, or maybe write my own.

evo2 · 02-02-2020, 11:50 PM

Hi,

Quote:

Originally Posted by Grainman

Ansible with SSH isn't really likely to work for this unfortunately because the Pis are small devices that move around (between various countries in Africa and Europe), so there's no way to predict which ones will be turned on or connected to the internet, or what IP addresses or hostnames they will have when they are on.

That actually sounds perfect for puppet which uses a pull model. When the machines are up and have network, regardless of where or when, they can automatically pull whatever configuration seetings are needed from the master.

Evo2.

Grainman · 02-03-2020, 12:27 AM

Quote:

Originally Posted by evo2

That actually sounds perfect for puppet which uses a pull model.

Yeah, Puppet is a better choice (and I believe Chef also uses a pull model), and I've used it before.

It seems overkill though to set up a whole server (obviously I'd actually use a VPS) for this, partially for the cost, but more importantly for the SysAdmin time. I'm hoping to avoid having to maintain Yet Another Server just to copy a few configuration files, install a few .debs, and clone a git repository.

There's also considerations like key management and the process of adding new Raspberry Pis. (I would love my client to be able to spool up another half-a-dozen Pis tomorrow without having to call me to edit the manifests)