Hi Wolf,

Wolf 写道：
> But it is not on the path:
>
>     root@gnu ~# pvcreate
>     bash: pvcreate: command not found

Indeed, lvm2(-static) wasn't actually installed on the 
installation image!

Commit 0906ce7389c6654fa3d1b3b52c8330eff0256264 fixes that:

  root@gnu ~# which pvcreate
  /run/current-system/profile/sbin/pvcreate

> On IRC I was advised to try guix install lvm2-static, which does 
> work
> (after sourcing the profile), however it does download the 
> package
> from the internet.

The installer image was generated using ‘guix system image’ with 
particular Guix version N.  Hence, all packages inside that image 
are those from Guix version N.  (In Guix, there is no ‘package 
repository’ distributed separately from the ‘package manager’.) 
These packages include the image's ‘guix’ package itself.

Hence, the ‘guix’ you can run in the image will always be older 
than the Guix that put lvm2-static in the image, and may contain 
older versions of some packages.

You'll have Guix N's lvm2-static in /gnu/store, but ‘guix install 
lvm2-static’ will install Guix N-1's version.  They might match, 
they might not.  I guess here they didn't.

>                    That seems pointless, since I already have 
>                    one
> locally (as seen in the output of find above), so I would prefer 
> to
> use that one.

You can simply

  root@gnu ~# guix install /gnu/store/84n[…]-lvm2-static-2.03.1

That might still download $things for $reasons, but they won't 
include lvm2-static.

> Another question is how to undo the effect of running herd start
> cow-store /mnt. I did try the obvious (herd stop cow-store), but 
> that
> does not seem to do the trick. So, how can I do it?

This I don't know either.  I always just reboot.

Kind regards,

T G-R