[Pkg-zfsonlinux-devel] Comparing the Debian and Ubuntu version of spl-linux

[Aron Xu]

On Wed, Sep 28, 2016 at 1:05 PM, Petter Reinholdtsen <pere at hungry.com> wrote:
> [Aron Xu]
>> Colin and I worked on the issues today and we are targeting to sync
>> spl/0.6.5.8-2 to Ubuntu yakkety directly. As for zfs the merge work
>> will continue, but it's too late in Ubuntu's release cycle, hopefully
>> we could do the real sync early next one.
>
> Nice.  Perhaps you can invoite Colin and others from the Ubuntu team to
> #debian-zfs?
>
> But it is unclear from the changelog why we integreated the hostid code.
> What is it good for?  Why have we not needed it before?  And why on
> earth is a host specific unique ID file a conffile on Ubuntu?
>
> And does it really make sense to have that code in the postinst?  I
> would imagine it made more sense to move it into a separate
> script/programm called from the postinst, and try to get the script into
> the coreutils package alongside the hostid program.  Or perhaps into
> glibc, which implement the gethostid() library function actually reading
> /etc/hostid.
>

We have that piece of code for a long time, what I've done is marking
it as non-conffile for upgrades from Ubuntu packages. In Ubuntu's
current packaging, a dumb /etc/hostid is shipped in spl package and
updated in postinst later, when users purging the package the file
will gone and the pool becomes foreign.

Upstream has changed not to import foreign pool when startup (disabled
zfs-import-scan.service by default), this makes it necessary that
hostid should not change when environment changes.


Regards,
Aron