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by trasz 1637 days ago
This doesn't really answer the question. Yes, the Linux API seems more flexible, but when you think about it, it really isn't, because all the models that actually make any sense can be implemented using simpler interface, which is what jails provide.

One real difference is that you need to be root to create a jail. It'll get fixed eventually - FreeBSD already has unprivileged chroot, jail isn't that much different.
1 comments
shatteredgate 1637 days ago
>Yes, the Linux API seems more flexible, but when you think about it, it really isn't, because all the models that actually make any sense can be implemented using simpler interface, which is what jails provide.

Not really, the example of Docker would probably be the most straightforward there. I don't think it's possible to fully port Docker to jails or at least I've never seen a successful port, some of the network topology features seem to just not be possible or straightforward. But I could be wrong, I have not looked into the technical details of this in years, somebody told me it might have been working a while ago but I never heard anything else about it since.

Needing to be root is a major deficiency though and I can't take jails seriously with that, one of the main focuses on Linux containers in the past several years has been to make unprivileged namespaces a good option.

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trasz 1637 days ago
Docker is literally just a jail. You can do whatever network topology you want using vnet.

And yes, having to use root is a major issue. Looks fixable though.

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shatteredgate 1637 days ago
Sorry, then I must be remembering some other issue. The effort to port docker to BSD seems to have disappeared.

>And yes, having to use root is a major issue. Looks fixable though.

AFAIK it took a long time to get this to work on Linux, there are a lot of security issues that it can cause.

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trasz 1637 days ago
Docker is practically dead, no wonder if disappeared :-)

Many things are hellishly complicated in Linux, due to politics and technical difficulties. Case in point: when I’ve started to work on NFSv4 ACLs, support in Linux was “worked on”, there was a prototype. It was 12 years ago. In FreeBSD, full supper for NFSv4 ACLs, from file systems to userspace tools, shipped decade ago. In Linux it’s still not there.

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shatteredgate 1637 days ago
Docker wasn't dead 5 or 6 years ago when I heard about this. In my experience some things are easier to implement in Linux and some are easier to implement in BSD. I don't particularly care for BSD's internal politics either, such as the licensing issues mentioned elsewhere here.
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trasz 1637 days ago
It might be because it would require reimplementing all the system-specific Docker parts from scratch. Not sure though.

BSD doesn't really have any licensing issues, thanks to BSD license, but politics is directly related to project size. In FreeBSD it's pretty much unnoticeable, but in Linux it can be a huge deal.

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nix23 1636 days ago
> It was 12 years ago. In FreeBSD, full supper for NFSv4 ACLs

You are right, but ironically we have to thank Microsoft for that ;)

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trasz 1636 days ago
Why, apart from inventing them (in Windows NT) in the first place?
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ori_b 1637 days ago
> Needing to be root is a major deficiency though

Note: Linux also needs root for its namespaces. Or at least CAP_SYS_SYSADMIN, which grants enough that it's pretty much as good as root. See setns(2) and clone(2) for details. This is one of the complaints the plan 9 people have always had with Linux namespaces.

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shatteredgate 1637 days ago
Not anymore, unprivileged user namespaces make it so you don't have to do that. That's how podman's "rootless containers" are able to work.
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