Add /etc/hosts file back

[mudler]

While it fixes things for from scratch installs, it breaks many things:

• we should generate an /etc/hosts file during boot, ideally in
  cloud-init phase, but that looks cumbersome as we can just relay on
  what's the default
• going to that route, and then excluding /proc, /sys, /run and /tmp
  requires further work on the bootstrap part, currently tests are not
  passing (see Exclude /proc and /sys #366)

It sounds easier instead to have a separate package for it just for
creating derivatives "from scratch" - in that way we don't interfere
with the standard system/cos which is supposed to run on ISO and other
medium too, where such folders are mandatory.

This addition adds a system/cos-container to just provide a separate package
with /proc, /run, /sys, /dev, /tmp stripped which is meant to be used for
from scratch scenarios.

Supersedes: #366

Signed-off-by: Ettore Di Giacinto [email protected]

[davidcassany]

mmm while I am totally in favor to get back /etc/hosts I believe the other folders still need to be cleared, otherwise is a bad design. I believe some failures are because the folder is excluded, but not its contents.

After second look I believe #366 mostly fails because it should have been

- ^/tmp/.*
- ^/proc/.*
- ^/sys/.*
- ^/run/.*
- ^/dev/.*

instead of

- ^/tmp
- ^/proc
- ^/sys
- ^/run
- ^/dev

some of these folders, if not all, are part of the readonly image, so at boot systemd can't create mountpoint.

[mudler]

- ^/tmp/.*
- ^/proc/.*
- ^/sys/.*
- ^/run/.*
- ^/dev/.*

Good point, but for the purpose of #366 excluding its content is not enough, luet will try to lchown directories too if they are present in the package. Let's say you do a mkdir foo, and chown it to something. Luet will try to reconstruct that on the host so even if empty that would hit lchown errors again.

That being said, I can try to add nevertheless

- ^/tmp/.*
- ^/proc/.*
- ^/sys/.*
- ^/run/.*
- ^/dev/.*

to the excludes of system/cos, as it sounds a good thing to add anyway 👍

[mudler]

@davidcassany added in 6b56092 👍

[davidcassany]

to the excludes of system/cos, as it sounds a good thing to add anyway 👍

I am not sure about /dev folder though... Probably I'd start without this one.

[mudler]

to the excludes of system/cos, as it sounds a good thing to add anyway +1

I am not sure about /dev folder though... Probably I'd start without this one.

Sure! I don't think anyhow we are recreating any of them with mknod, so should be safe

[mudler]

ok, something is not ok by excluding those files, I'll split that in a separate PR

[mudler]

All required tests are passing, merging