Linux To Introduce The Ability To Set The Hostname Before Userspace Starts

[sinepgib]

It's been possible to give a kernel a custom hostname since ages ago.
CONFIG_DEFAULT_HOSTNAME. By default it's "(none)" iirc.
So it's not like the kernel won't answer with a hostname.

It will. But not a cmdline dynamic one.

I was going to mention this. But, of course, this isn't really usable for default kernels in a regular distro. I think it's more tailored for embedded where you know the hostname in advance (the owner is not expected to change it) and you build your kernel anyway.

[AlanTuring69]

I fail to see how this benefits anyone? Does anyone seriously use RAID, despite its obvious flaws if one of the disks go bad? And I thought Linux was supposed to be UNIX-like. Honestly, engineers really shouldn't be responsible for kernel development anymore since their priorities are clearly wrong. They keep adding new, complicated features to support a /bin/sh-less environment but their only focus should be improving the shell system. Kind of seems like Poetterware to me. How else will my great grandmother continue to author beautiful /bin/sh scripts from her TI-82 when she has to recompile the L*nux kernel every 2 years?

[moltonel]

It's been possible to give a kernel a custom hostname since ages ago.

Absolutely. Setting the hostname in your bootloader config is a very niche requirement. Setting the hostname at kernel compile time or during userspace boot has been good enough for decades. This patch will find its users, but it's not a headline new feature.

[rene]

It can be used by mdadm which is server thing (well, desktop too if you want to have RAID array on your desktop for some reason) and Linux is pretty popular on servers. So yeah, it is important.

so important that nobody needed that in 30 years, servers I have seen usually used UUID, WWN and usually not mdadm ;-)

[dragon321]

how important. Surely this will finally make it the year of the Linux desktop! ;-)

It can be used by mdadm which is server thing (well, desktop too if you want to have RAID array on your desktop for some reason) and Linux is pretty popular on servers. So yeah, it is important.

[ClosedSource]

Is there any chance that this is going to be backported?

To what?
Stable trees? unlikely.
Your distribution's kernel? Pretty much up to them.

[Delgarde]

So I can understand some people wanting this backported for making locked system images but you want to be able to start the system images with different hostname values for identify self to network.

Yeah, I can imagine this would be useful for two cases in particular — network boot and virtual machines. It's the kind of thing you want for running datacentres, where all this stuff is handled by some orchestration infrastructure rather than local configuration.

[rene]

how important. Surely this will finally make it the year of the Linux desktop! ;-)

[milkylainen]

It's been possible to give a kernel a custom hostname since ages ago.
CONFIG_DEFAULT_HOSTNAME. By default it's "(none)" iirc.
So it's not like the kernel won't answer with a hostname.

It will. But not a cmdline dynamic one.

[Emmanuel Deloget]

I think his point was the typo - "With mdadm it relies upon hosrtname matching..."

Interesting info about locking the hostname after early init (or potentially even earlier now), though. That had never occurred to me.

This is not typical in the desktop world, where you can leave a few millisecond before the hostname is set. But it's an important part of the very early init on many servers and on many embedded devices. This is something I dreamt of multiple times - being able to feed the hostname directly from the uboot command line is a big plus for me.

So kudoes to Andrew for this!