3 ms·

How much overlap is there between OpenBSD, FreeBSD, and NetBSD? Like can I use the FreeBSD one to learn how to use the other BSDs?

protomyth 5y ago
In a general sense, and a lot of commands are the same, but they are very different for a lot of stuff. Compare https://docs.freebsd.org/en/books/handbook/ https://docs.freebsd.org/en/books/handbook/ to https://www.openbsd.org/faq/index.html https://www.openbsd.org/faq/index.html and you can see the large differences.
spijdar 5y ago
This isn't a direct answer, but I think it'll help understand their relationship/how similar they're likely to be. All of the above are descendants of an OS that Berkeley released called "BSD". BSD only ran on PDP-11s, and then, VAX minicomputers, with a few proprietary ports to expensive workstations (SunOS, Sony NEWS, etc). The code was a "distribution" of modifications on top of AT&T UNIX, so it couldn't be freely shared to people without a UNIX license. So the developers released part of their own code separately, the most important released called "Net/2". Two alumni of Berkeley worked on expanding the free distribution to be 1) a full OS and 2) run on regular Intel 80386 PC clones. This was called "386BSD". The last "official" BSD was 4.4BSD, which had the goal of wider software and hardware compatibility, adding support for a wide range of computers. Disagreements with the developers of 386BSD led to a fork, eventually named "FreeBSD" (as in Free86BSD, I think). They continued the goal of a PC compatible BSD. Another group took 386BSD and reintegrated 4.4BSD code back in, continuing the Berkeley goal of "wide hardware compatibility", which became NetBSD. "Internal disagreements" eventually led to one of the core developers leaving to make OpenBSD, which differed in that the development source repository was always publicly available (at the time NetBSD only released source for a full release, only team members could pull from the CVS repo). All that to say, FreeBSD is sort of its own thing, with NetBSD and OpenBSD sharing much more. They've all diverged quite a bit, but have simultaneously shared a lot of code (especially things like device drivers). So, broadly speaking, using any BSD will make you "familiar with BSD", but they really are quite distinct at this point.
GekkePrutser 5y ago
Not really. They have the same origins but totally different focus and have been apart for so long that they are substantially different. Though they borrow stuff from each other. And even Linux does (OpenSSH for example comes from OpenBSD). In general FreeBSD is a great allrounder with up to date packages. OpenBSD is very focused on security and it's pretty minimalist as a result though you can install what you want. NetBSD strives to support as many hardware platforms as possible so it's a good choice for that weird old server you found on ebay. They had more similar goals in the past but this is how they've diversified (at least how I see it!) Besides these focus differences there's also some personalities behind the different BSDs that make Linus look like a kitten :) So that tends to influence people's OS of choice as well. I don't want to get involved in that but I wanted to give the heads-up because it will come up in discussions once you start looking into the BSDs.
- chalst 5y ago
  I kind of think NetBSD doesn't so much 'strive' to support many platforms as try to pursue simplicity of implementation and so be easy to port. Linux supports a lot of platforms, but porting Linux is a much more heroic effort. The NetBSD codebase is nice for studying operating system concepts.

protomyth 5y ago

In a general sense, and a lot of commands are the same, but they are very different for a lot of stuff. Compare https://docs.freebsd.org/en/books/handbook/ https://docs.freebsd.org/en/books/handbook/ to https://www.openbsd.org/faq/index.html https://www.openbsd.org/faq/index.html and you can see the large differences.

spijdar 5y ago

This isn't a direct answer, but I think it'll help understand their relationship/how similar they're likely to be. All of the above are descendants of an OS that Berkeley released called "BSD". BSD only ran on PDP-11s, and then, VAX minicomputers, with a few proprietary ports to expensive workstations (SunOS, Sony NEWS, etc). The code was a "distribution" of modifications on top of AT&T UNIX, so it couldn't be freely shared to people without a UNIX license. So the developers released part of their own code separately, the most important released called "Net/2". Two alumni of Berkeley worked on expanding the free distribution to be 1) a full OS and 2) run on regular Intel 80386 PC clones. This was called "386BSD". The last "official" BSD was 4.4BSD, which had the goal of wider software and hardware compatibility, adding support for a wide range of computers. Disagreements with the developers of 386BSD led to a fork, eventually named "FreeBSD" (as in Free86BSD, I think). They continued the goal of a PC compatible BSD. Another group took 386BSD and reintegrated 4.4BSD code back in, continuing the Berkeley goal of "wide hardware compatibility", which became NetBSD. "Internal disagreements" eventually led to one of the core developers leaving to make OpenBSD, which differed in that the development source repository was always publicly available (at the time NetBSD only released source for a full release, only team members could pull from the CVS repo). All that to say, FreeBSD is sort of its own thing, with NetBSD and OpenBSD sharing much more. They've all diverged quite a bit, but have simultaneously shared a lot of code (especially things like device drivers). So, broadly speaking, using any BSD will make you "familiar with BSD", but they really are quite distinct at this point.

GekkePrutser 5y ago

Not really. They have the same origins but totally different focus and have been apart for so long that they are substantially different. Though they borrow stuff from each other. And even Linux does (OpenSSH for example comes from OpenBSD). In general FreeBSD is a great allrounder with up to date packages. OpenBSD is very focused on security and it's pretty minimalist as a result though you can install what you want. NetBSD strives to support as many hardware platforms as possible so it's a good choice for that weird old server you found on ebay. They had more similar goals in the past but this is how they've diversified (at least how I see it!) Besides these focus differences there's also some personalities behind the different BSDs that make Linus look like a kitten :) So that tends to influence people's OS of choice as well. I don't want to get involved in that but I wanted to give the heads-up because it will come up in discussions once you start looking into the BSDs.

chalst 5y ago
I kind of think NetBSD doesn't so much 'strive' to support many platforms as try to pursue simplicity of implementation and so be easy to port. Linux supports a lot of platforms, but porting Linux is a much more heroic effort. The NetBSD codebase is nice for studying operating system concepts.