Add support for NetBSD

[darkgeek]

Hi,

I want to add some code to make Nomad build and run on NetBSD.

In this PR, allocdir/fs_netbsd.go and host/netbsd.go are used for NetBSD only, while the df part in host/unix.go is reworked, which might affect other Linux/Unix: instead of leveraging on the frozen syscall package, where Statfs is not available on NetBSD, it might be better to switch to gopsutil, which supports more platforms (currently it doesn't support NetBSD though, I have also sent a PR shirou/gopsutil#1530 to it).

Can you check this PR to see if it's decent enough to be merged? Thanks.

[hashicorp-cla]

All committers have signed the CLA.

[tgross]

Hi @darkgeek! Thanks for opening this PR. A few comments other than the remarks I've left inline:

• Does this need for gopsutil to cut a tag with Add some support for NetBSD shirou/gopsutil#1530, and then for Nomad to pick up that dependency bump in the go.mod?
• Is this actually enough to run workloads? What task drivers are you using to verify this?

[tgross]

It looks like we're missing this same function for other non-Linux/Darwin Unixes (which makes me wonder if any of the BSDs can build?). Should this be a unix build tag instead of a netbsd build tag?

[darkgeek]

OK, I deleted darwin.go, linux.go, netbsd.go, and moved the mountedPaths() function to unix.go with unix build tag in this commit: 1c61ce3.

Then I tried on Linux and NetBSD, it built and ran well like before. Though my tests are quite limited.

[darkgeek]

Hi @darkgeek! Thanks for opening this PR. A few comments other than the remarks I've left inline:

• Does this need for gopsutil to cut a tag with Add some support for NetBSD shirou/gopsutil#1530, and then for Nomad to pick up that dependency bump in the go.mod?

Yes, my PR has been merged, and gopsutil already has NetBSD support since the v3.23.9 tag, so you might consider bumping to this version.

• Is this actually enough to run workloads? What task drivers are you using to verify this?

It's enough to (and only can) run raw_exec workloads perfectly on my NetBSD aarch64 box:

[tgross]

Yes, my PR has been merged, and gopsutil already has NetBSD support since the v3.23.9 tag, so you might consider bumping to this version.

Ok, but in which case we should do that in this same PR.

[darkgeek]

Yes, my PR has been merged, and gopsutil already has NetBSD support since the v3.23.9 tag, so you might consider bumping to this version.

Ok, but in which case we should do that in this same PR.

OK, I did that in the commit b1cd0a9, and have tested on my NetBSD box.

[tgross]

@darkgeek you've got some merge conflicts here you'll need to resolve.

[darkgeek]

@darkgeek you've got some merge conflicts here you'll need to resolve.

Resolved by doing rebase on main. And I also squash my previous commits to a single one.

[tgross]

LGTM!

I've tested this out on Linux and I've had one of my colleagues who's on macOS give this a spin just to make sure nothing got broken there. I've added a changelog entry as well. Once this is green in CI we'll merge it and it'll go out in the upcoming Nomad 1.7.0 release.

Thanks @darkgeek!

[tgross]

The test-ui/finalize failure is because of some weird CI issue we have around not exposing the token for Percy to external contributors. That needs to get fixed but isn't a blocker for you here (especially as this isn't a UI PR 😀 )