[tinco]

Just for clarification, because zoltan isn't making very compelling arguments.

Docker made containers easy and effective. Solaris zones were not as good as Docker is, BSD jails are/were not as good or easy to use as Docker is. Popularity has nothing to do with it, except that the popularity is an indication of the fact that Docker was revolutionary in the way it made these technologies accessible to a very large professional audience.

Docker was not created in isolation, it was inspired by jails and zones and all the fancy new features that were added to the linux kernel at the time.

Using just the words FROM, ADD and CMD, you can make a container definition that effectively isolates a runtime for just about any application in a 3 lines. Beyond the couple simple keywords all you need to have is absolutely basic linux knowledge, the level you can teach any developer in an afternoon.

There's no need to pollute that developers mind with any other system administration garbage. Nothing about networking, policies, filesystems, whatever. Just basic bash and a couple keywords.

Then when you want to go to production, you just hand the shit your developers wrote over to a professional system administrator and they'll make it run perfect at any scale. It's magic. Before Docker the world was darkness and bullshit, and after Docker the world was drenched in light and all that is good.

The fact that it's 2022 and there's still people that are going "hur-dur Solaris zones, BSD jails amiright" as if any of those technologies have any relevance is ridiculous.

Docker is technologically excellent.

[laumars]

I was with you right up until this part:

> The fact that it's 2022 and there's still people that are going "hur-dur Solaris zones, BSD jails amiright" as if any of those technologies have any relevance is ridiculous.

Having diversity in the computing ecosystem is a good thing, not bad.

I'll take your point that Docker brought containers to the developers (frankly, I made that point myself) but that doesn't mean that Jails doesn't solve some problems that Docker (currently) struggles with. Nor does Docker's success mean that a little competition isn't healthy for the wider industry.

Dismissing the stuff that went before it as "systems administration garbage" because it was targeted at a different audience to yourself is a really poor attitude in my opinion. Especially when there are countless examples of when audiences different from developers also need to make use of software. Frankly, I thought by now we were past the sysadmin vs developer flamewars. But clearly not.

Aside from that minor rant, I do want to thank for your post. It was an informative read.

[tinco]

My apologies, I meant relevance to the problem that Docker solves, which is enabling developers to neatly specify and package their dependencies. I am not trying to diminish jails and zones usefulness to system administrators. I'm just saying if you put Docker in a comparison list to other technologies, jails and zones wouldn't even be in that list.

The annoyance comes from system administrators looking at the set of technologies inside Docker and saying "we already have that", and then just assuming Docker must be some sort of marketing scheme. I deployed docker in my organisation within a week of its first (beta?) release, when all of its "marketing" was a single blog post.

Docker solved an enormous real problem in the software industry, even if from a system administrators perspective it's just a new way of packaging applications, as there have been many in the past and probably will be many in the future.

[laumars]

Oh I never meant any of my comments to undermine Docker. While I do have some specific frustrations with Docker, the same is true with any technology stack: Jails and Zones included.

I'd never describe Docker as being a marketing gimmick. It was definitely a "right time, right place" tool. But that speaks more about how the market (and particularly Linux) was yearning for something better.

Thanks for the interesting conversation :)

[brazzledazzle]

Docker is the best because it did something its predecessors could not: made it accessible, easy to run and easy to share. On Linux. Now the technology has industry standardization and so much inertia it’s surviving the monetization drive by docker (the company). The existing software out there was sysadmin stuff because it was mostly DIY. Or required learning to administer and build tooling for another OS.

[mike_hearn]

It's worth noting that Docker was primarily a godsend for people working in scripting languages like Ruby or Python, where they have very messy packaging systems, depend on tons of native Linux libraries and so on.

For people working on the JVM the world was in some sense already 'drenched in light'. You could just send the sysadmin a fat jar you developed on Windows or macOS and tell them to deploy it, done. Or maybe you'd use an app server, so you'd send a less fat jar and they'd deploy it via a GUI and it already gets high level services like db connections, backups, message queues etc.

Also, Docker doesn't really solve the common case of an app that depends on a DB, maybe email etc. Those are services that need administration, you can't just start up a random server and expect things to go well. At least you need backups, proper access control and so on.

So deployment difficulty was very much dependent on what ecosystem you were in.

[tinco]

That's certainly true and describes my circumstances at the time. But it's also good to note that it is great for C/C++ dependencies as well, our GIS applications require PROJ, and our machine learning projects various Nvidia cuda things.

Also, just last week I needed new smbd features, and the only way to deploy a recent smbd version whilst retaining sanity seems on Ubuntu seems to be to just use docker. Normally there's a PPA but there wasn't in this case for some reason.

[nunez]

That's _before_ we consider that most folks aren't running BSD or Solaris, in any capacity, and that jails were never truly ported over to Linux.