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> idempotency implies that Ansible always starts from nothing and builds from there

No, it doesn't. In Ansible you say something like "make sure apache is installed" and if apache is installed, nothing happens. If it isn't, it gets installed. Then you say "make sure apache is running" and if apache is running, nothing happens. If it isn't, it is started.

Okay, this is a rather limited form of idempotency. I don't see the advantage. My system's package manager and service manager already perform this function.

You should really spend a little time learning ansible before you critique it. Ansible isn't perfect, but the things you describe aren't how ansible works in general, so they aren't even valid criticism.

For example, it has idempotent modules for all sorts of things - contents in files, files and directories in the file system, etc - things that you COULD script in an ad-hoc and verbose way, but things which come built-in as one-liners in ansible.

It's quite convenient.

There are no resources which are seemingly suitable for my environment. If you're going to claim that I'm missing something, rather than telling me that I have things to learn (no shit sherlock), you could tell me specifically which initial impressions are wrong.

I did, a few comments up. This:

> idempotency implies that Ansible always starts from nothing and builds from there

...is wrong. It might be true that Ansible is unusable in your environment for some reason, but that's quite different fromage this specific false claim.

Here are a few more quotes that imply you should learn about Ansible before critiquing it for your use case (or, if you don't have time, then refrain from critiquing it in general):

> Don't I still need to know shell programming for Ansible?

No, Ansible uses a custom non-shell syntax and python modules. You can dip into shell scripts but you don't have to. Examples are everywhere in the Ansible documentation.

> Does this mean that every time I want to change my server I have to wait 15 minutes for it to re-install the distro and re-configure everything?

No. Ansible will examine your existing system and apply the changes you configure. Idempotency does not imply or require a functional-like OS or rebuilding from scratch; Ansible is more imperative.

> Don't I still need to know shell programming for Ansible?

No. Ansible has its own built in functions for creating files, managing systemd, docker and so on. These are built with idempotency in mind.

You can however call out to shell for situations where there is no built in. There are a lot of people who only ever use this role, and just see ansible as the fleet orchestration layer. Which imo defeats most of the benefits of using it, you might as well ssh a full script in that case.

As a side note I wouldn’t actually recommend Ansible for server management. Like you say learning all these blessed roles feels like relearning basics you already know and the syntax and directory structure is messy. It has no place if you use containers.

> Ansible has its own built in functions for creating files, managing systemd, docker and so on. These are built with idempotency in mind.

Do I still get idempotency if I do not use systemd or docker?

> You can however call out to shell for situations where there is no built in. There are a lot of people who only ever use this role, and just see ansible as the fleet orchestration layer. Which imo defeats most of the benefits of using it, you might as well ssh a full script in that case.

So it sounds like I wasn't entirely wrong in my first impressions that it would be useless for my situation where I don't think any of the "built ins" would really be suitable. Of the 8 machines on my network, only one has systemd (and I'm in the process of phasing it out because systemd seriously struggles to deal with services with dependencies on specific network interfaces being "UP", these issues are documented by freedesktop[0]).

> As a side note I wouldn’t actually recommend Ansible for server management.

Given the background of my infrastructure being a mixture of FreeBSD, OpenBSD, non-systemd Linux and systemd Linux machines. What would you recommend?

[0]: https://www.freedesktop.org/wiki/Software/systemd/NetworkTar...

You seem to have a very strong opinion about Ansible while you keep emphasizing that you don’t know anything about Ansible at the same time.

As a result, all your arguments against Ansible seem to be based upon assumptions, some of them completely false.

I have opinions of my limited experience of trying to look into ansible once.

Why don't you tell me which "arguments" (correction, they're my opinions) are based on false "assumptions" (correction, they're my impressions) rather than just giving me this blanket statement to work from?

If you already have something that works, by all means, stick with it.

If you want to learn Ansible, you don't even have to throw away your scripts; Ansible is a perfectly good way to run ad-hoc scripts if that solves your problem better than writing a full-blown playbook or even a custom module.

Ansible is weird and annoying in the beginning, but it's still a good tool to learn on top of your existing knowledge, because it provides extremely useful features beyond what's possible with plain old shell, and more importantly, it's a common language for system administration tasks that anyone can learn and understand without having to figure out how your specific scripts accomplish the things that Ansible gives you for free. The same applies to any management tool like Terraform, Puppet or even Kubernetes manifests. I put my expertise in my Ansible scripts and provide an easy interface to them such that a more junior person can, say, upgrade an Elasticsearch cluster by issuing a documented "make upgrade" (I like to use Makefiles to provide a neat interface for "standard" operations. "make help" and anyone can get going.) command that does everything correctly even though they have no idea how to actually upgrade it manually. If they wanted to learn, they have all the resources available required to read and understand my playbooks and figure it out without me being there to teach them the particulars of whatever unholy custom script setup I might have used instead.

Ansible is also mostly useful once you already have a server up and running but with 0 configuration; it's pretty bad at actually installing new servers, and I'd recommend using better tools for that part (Terraform, kickstart, or maybe just a script that clones an image). Just a manual next-next-next install is also perfectly acceptable way to get the base OS installed if the defaults are fine, though beyond a few servers it's a good idea to have a better process.

My perspective is that of someone who works with very varied systems daily, ranging in size from one to hundreds of nodes. I can manage that kind of scale alone because I use automation, and Ansible in particular is a tool that fits extremely well in the 1-20 "size range" for an environment; It is extremely lightweight and low-investment and can be used for even single nodes to great effect; once you get beyond a couple dozen, something more "heavyweight" like Puppet will start showing its usefulness.

As for idempotency, it's a very useful feature for automation: basically "Only do something if it is required". With a shell script, you have to implement manual checks for everything you run such that if you re-run a script on a system where it's already been run once, you won't accidentally break things by applying some things twice. A side benefit of this is that you can run your playbooks in "check mode", ie. "Tell me what you would do, but don't actually do it". Extremely useful and very error-prone to implement manually (Ansible doesn't always get it right either).

> With a shell script, you have to implement manual checks for everything you run such that if you re-run a script on a system where it's already been run once, you won't accidentally break things by applying some things twice

Using tools like grep + basic logic like || and && goes a long way...

I'm not saying there is no place for ansible, but in my personal experience, it's a very small one.

> Ansible is also mostly useful once you already have a server up and running but with 0 configuration; it's pretty bad at actually installing new servers, and I'd recommend using better tools for that part (Terraform, kickstart, or maybe just a script that clones an image).

Agreed!

More recently, I've found zfs clones of base installs surprisingly flexible.

Now I only with there was a way to do some kind of merge or reconciliation of zfs snapshots from a common ancestor that haven't diverged much in practice, spawning the differences into separate datasets per subdirectory (ex: if /a/ hasn't changed but only /a/b/c/d1 and /a/b/c/d2 differs, move d1 and d2 off to create a separate d dataset mounted in /a/b/c/ so you can keep the common parts identical )