Over the past few years, a plethora of orchestration frameworks have been exploding onto the scene. Many have been around for quite a while but not all have the same sort of community behind them. For example there's a very interesting option in Joey Hess' Propellor but that is hurt by needing to be able to build Propellor on all the hosts you manage. On the other hand, Ansible is able to operate without installing extra software on your target hosts, but instead it ends up very latency-bound which can cause problems when your managed hosts are "far away".

I have considered CFEngine, Chef, Puppet and Salt in addition to the above mentioned options, but none of them feel quite right to me. I am looking for a way to manage a small number of hosts, at least one of which is not always online (my laptop) and all of which are essentially snowflakes whose sparkleybits I want some reasonable control over.

I have a few basic requirements which I worry would be hard to meet -- I want to be able to make changes to my hosts by editing a file and committing/pushing it to a git server. I want to be able to manage a host entirely over SSH from one or more systems, ideally without having to install the orchestration software on the target host, but where if the software is present it will get used to accelerate matters. I don't want to have to install Ruby or PHP on any system in order to have orchestration, and some of the systems I wish to manage simply can't compile Haskell stuff sanely. I'm not desperately interested in learning yet more DSLs, but I appreciate that it will be necessary, but I really don't want to have to learn more than one DSL simply to run one frameworks.

I don't want to have to learn strange and confusing combinations of file formats. For example, Ansible quite sensibly uses YAML for its structured data except for its host/group lists. It uses Jinja2 for its templating and looping, except for some things which it generates its own looping constructs inside its YAML. I also personally find Ansible's sportsball oriented terminology to be confusing, but that might just be me.

So what I'm hoping is that someone will be able to point me at a project which combines all the wonderful features of the above, with a need to learn only one DSL and which doesn't require to be installed on the managed host but which can benefit from being so installed, is driven from git, and won't hurt my already overly burdened brain.

Dear Lazyweb, pls. kthxbye.

puppet or propellor here

you are going to have trouble not installing software. even ansible pretends not to install anything, when in fact, it does deploy a bunch of Python code on the other side and assumes you have some version of python installed as well (which is now pretty much universal in Debian, but still)...

Yansible drives me nuts: they basically built a DSL on top of YAML, with Jinja in there, and it's not quite clear to me how it is an improvement over pure Python (or why that isn't the default) or a DSL like Puppet's.

I use Puppet at $work. It's probably because it was the only thing available besides cfengine back then and now that I learned it, i don't want to bother learning something else or (worse) converting the thousands of lines of code we have running in Puppet into something else. Puppet is also pretty flexible: you can use a central server, but you can also run locally with manifests checked out of git. Some friends are running it through gpg-validated git hooks in a decentralized manner, so i know that's possible as well. You'd have to learn a DSL, so it's annoying, but the DSL is not so bad, although it changes too quickly to my taste.

Starting again, I may go with Chef, but I'm not sure i want to rely on Ruby for anything, after running into problems with it with Puppet and Redmine.

If configuration management wouldn't be my day job, I would go with Propellor, especially with your requirements. I like the idea of not building a new DSL (or at least, making one based on a real language, as opposed to freaking YAML or a completely new language like Puppet). And joeyh builds stuff to last, so I trust him. Of course, Haskell needs to work, but then GHC seems to run pretty much everywhere Debian runs, according to the build logs so I'd be curious to hear what platforms you are having problems with.

The problem with Propellor, of course, aside from Haskell, is that it isn't meant to be a serious project (yet?). The API is changing quickly and it's mostly a hobby project right now. But it could be fine for personnal projects.

For my personal stuff, i manage around 3 personal hosts (laptop, workstation at home and in the office). I just run etckeeper to keep an eye on /etc, put /home under git as well, and sync stuff around by hand, including package lists. I gave up on using Puppet on theses, too much overhead for too few machines.

Hoping that helps...

Comment by anarcat [id.koumbit.net]

It’s there, and easy to use. Ph33r the mighty power of the Korn Shell!

When I arrived at the current $orkplace there was a system in action that downloaded and ran a script every 10 minutes, as root. I was shocked.

The system is still in use, maintained by me, and has so far survived all attempts by other admins (most of which came to the company even later) to replace it with e.g. puppet, has been robust yet simple to use. It now also calls out to a CGI for some basic monitoring (we have another CGI that displays an overview page) and can signal problems (such as “no NTP running” or “Java < 7 installed”), which make the host line on the overview page a signalling colour. The script installed on the servers that does the actual downloading and running exports some useful info before (hostname, MAC of the primary interface, OS, version, host type/class, etc).

Comment by mirabilos

I have been working with ansible for the past few months. I've chosen it because of two things mainly: it's push-based and you don't have to install anything on the targets. I would try salt, as installing just that is not much of a deal.

The thing is actually pretty powerful, but the biggest problem it has is the mess they did with YAML and Jinja. It is really badly designed (I'd say not designed at all). You never know for sure when the Jinja parts are evaluated, the variables don't have clear precedence rules, much less scopes. All this makes writing nice, reusable roles very hard. I'd say that if you just rewrote the front-end, using a better DSL, Ansible could be a killer.

Comment by Martín Ferrari
comment 3

Propellor has some nasceant ability to run on a host without ghc. It does this by sending over a precompiled binary along with all the libraries it needs. Currently this is only done when the host doesn't seem to have a functional apt at all -- I implemented it for OS takeover purposes -- but it wouldn't be hard to add a property to a host that makes propellor always use this mode when spinning it. Of course architecture compatibility limitations apply. Also, it means uploading some number of megabytes (around 10 IIRC) each time. It might be possible to use rsync to get the bandwidth usable somewhat more tractable.

Relevant code is in sendPrecompiled

Comment by joeyh.name
Look at Cosmos

Your post prompted me to write something about the system I have been using for my servers/laptops for a couple of years now.... I hope you can find some inspiration in Cosmos. See writeup here:



Comment by josefsson.org