Re: Network Boot Get Hostname In grub.cfg

[Federico Vaga]

Hi Andrei,

I'm sorry for the late reply but I never received your email which I
just found on the help-grub archive.

On 11.11.2021 22:00, Andrei Borzenkov wrote:
> On 11.11.2021 12:36, Federico Vaga wrote:
> > Hello,
> > 
> > I'm trying to get the hostname in `grub.cfg` to point then to
> > different rootnfs, or network live images.
> > 
> > From the manual page:
> > 
> > https://www.gnu.org/software/grub/manual/grub/grub.html
> > 
> > I've noticed the existence of `net_<interface>_hostname` but this
> > requires to know the `<interface>` name in advance and this is
> > platform dependent (as the documentation says).
> > 
> > Since these systems have only one network connection I thought about
> > using `net_default_interface` to ignore the specific name. Here
> > problems strarts because neasting variables seems not working and
> > doing: `${net_${net_default_interface}_hostname}`
> > 
>
> eval "set myhostname=\${net_${net_default_interface}_hostname}"
>
> and use $myhostname in following code

How this is different from just using `set` or the variable directly?
Why `eval` should help? (It doesn't)

Plus, why are you escaping the first dollar, but not the second?

> > However, in the documentation variables like `net_default_ip` are
> > described as the result of ‘net_${net_default_interface}_ip’.
> > 
> > Am I doing something wrong? Do you have any suggestion?
> > 
> > Thanks
> >