Docker is no more…
… anyway in Red Hat Enterprise Linux 8. And while the title may look a bit provoking – it really is the case. But before you start swearing – please let me assure you that Red Hat stays fully professional and focused on consumers satisfaction.
So…? You guessed it, there is something much, much better.
It’s Podman (plus assisting tools).
Yeah, but you don’t want to learn new tool again, right? You don’t need to – Podman is fully backwards compatible, and while being entirely different tool below, it remains familiar.
„docker build? podman build”
„docker run? podman run”
„docker push? podman push”
And so on. 99% of docker options remains the same with Podman.
It gets even better – you might want to use former, docker calls – no worries, just install podman-docker package and you’re ready. You keep using „docker $command”. This way, you can preserve your scripts entirely, nothing changes from user point of view.
What does change then? A lot to be honest.
First of – security, and a few other things
But first things first. What did happen, that Red Hat changed good old Docker to Podman? Docker went its way, which did not went well with Red Hat way. While it’s a great tool, outstanding software – Docker has its pains.
It has aged a bit. Well, not really nice. Please, don’t get me wrong – this is not the fault of Docker. This software was built at a point of time when certain mechanisms we have today – did not exist.
Next thing – do you already see it?
Yes, Docker is not only tool for containers. In USA during eighties – „IBM” and „PC” were synonyms. Does it mean all PC’s came from IBM? No, but the market share of IBM was so huge – people used name of the company and „Personal Computer” exchangeably.
Same happened with Docker – for many it still means containers. „Dockerization” and „Containerization” mean the same thing for many people.
But with time, when more and more vendors came with their solutions for PC’s, market had grown – IBM stopped to be a synonym to PC. Sure, we used to use both terms exchangeable for some time, but at one point being aware that it is only our habit.
Over a time – same thing will happen with Docker – and while I still did not learn to predict future – it is pretty natural thing, so I’m almost sure it will happen. And Podman is one of the answers to the call for something „better”…? In a sense – yes.
There exists a number of software which got built „by an accident”, and even with all of downsides – were so great – that we lived with it. But over the time, when requirements grown, this software got improved so much – it does not „resemble” it’s origins at all.
Remember the pain SELinux was? SELinux is not a pain anymore, it’s great stuff!
OK, maybe RHV? Remember the first versions? Nowadays it competes with industry standards.
Maybe something closer to Docker? Sure – OpenShift. If you show release 1.0 to the person who got used to current 4.x, probably the person won’t see a bit of similarity.
Next – the Linux itself. And I do not need to remind you kernel 1.0
Remember the difference and the gap between 2.4 and 2.6? Or maybe the difference between systemd and initd? It wasn’t that long time ago – last release of Slackware still stays with initd. And the difference? If you know what I’m talking about – you know for yourself, and if you don’t – I honestly encourage you to check yourself – it is huge.
As for containerization, it is the same. While from the user point of view, almost nothing, or entirely nothing changes – mechanism is so much better with Podman, that you simply don’t want to come back to Docker.
No more deamon with root privileges, actually – no deamon at all. Maintained images, SELinux, and full Red Hat maintenance with ongoing new releases.
Second – stability
Since Red Hat maintains it on their own – this gets an ongoing process, like with security. With Podman you receive more mature mechanism, that is free of some issues that docker still has. This directly means that you keep things your way, the way you used to. And while keeping your habits, you receive proper software, that will define future industry standards.
If you prefer to stay with Docker – you can do so, though trust me – there is no reason for it.
The same no reason for Red Hat to support it beyond RHEL7.
Summarizing – Docker in RHEL 8 is no more.
But there is something better. Way better.
You can start using it already – RHEL 8 got released over half a year prior to me writing these words. The system is getting mature, and one of its great features is containerization – done the right way.
Please let me know what you think, have I convinced you?
I hope I did – cause it is for your own best!! 🙂
08:16 AM, Feb 20
Technical Support Engineer
Technical Support Engineer at Veracomp, responsible for the Red Hat brand. He has 10 years of experience in the IT industry, from the beginning he has been associated with Linux-based products.