[arch-general] Partition mounting in systemd [WAS: Lennart Poettering on udev-systemd]

[Baho Utot]

On 08/15/2012 11:01 AM, C Anthony Risinger wrote:
> On Wed, Aug 15, 2012 at 6:38 AM, Baho Utot <baho-utot at columbus.rr.com> wrote:
>> On 08/14/2012 08:53 PM, Oon-Ee Ng wrote:
>>> On Wed, Aug 15, 2012 at 8:13 AM, Tom Gundersen <teg at jklm.no> wrote:
>>>> On Wed, Aug 15, 2012 at 1:55 AM, David Benfell
>>>> <benfell at parts-unknown.org> wrote:
>>>>> Does systemd not use the standard
>>>>> mount program and follow /etc/fstab?
>>>> It does. Though it does not use "mount -a", but rather mounts each fs
>>>> separately.
>>>
>> [putolin]
>>
>> I came across another anomaly on my systemd boxes that I would like someone
>> to verify if they could.  Please do this on a backup system.
>>
>> I was changing some lvm partitions about that were mounted in /etc/fstab,
>> actually I removed them and created two new lvm partitions with different
>> names, but failed to update the fstab. Upon rebooting the systems failed to
>> boot and where stuck at trying to mount the non existing lvm partitions.  I
>> could not fix the systems as I could not get a "recovery" bash prompt.  I
>> had to use a boot live CD to edit the fstab and then all was well. On all my
>> sysvinit systems a bad mount point would just give me an error and continue
>> booting.
>>
>> Could some brave enterprising soul confirm this?
>>
>> This created the following question: Can systemd boot a system without a
>> fstab?
> you would have to provide the mountpoints -- depending on what you
> were mounting i'm quite sure initscripts would fail (/usr? /var? what
> was changed??), though they may very well just keep chugging on,
> pretending all is well.
>
> root mount depends on nothing more than what's listed on the kernel
> cmdline in grub.cfg or equivalent.  you could have also added
> `break=y` (legacy form, i forget the new syntax) to open a shell in
> the initramfs and correct from there.
>
> AFAIK systemd doesn't NEED an fstab, but you would then need to
> provide native *.mount files instead ... SOMETHING has to tell it
> where the mounts go, yes?
>

I don't know what your pointing out here


What I had was /dev/lvm/lfs and /dev/lvm/LFS in the fstab.  These where 
mounted into /mnt/lfs and /mnt/lfs/LFS

I removed those from lvm and created /dev/lvm/wip and /dev/lvm/WIP and I 
did not remove the /dev/lvm/lfs and /dev/lvm/LFS from the fstab file, 
then rebooted.

As far as I could tell systemd rolled over because it could not mount 
the lfs and LFS lvm partitions, because they where not there.
It just hung waiting for mount points that just wasn't going to showup 
no matter what.  I could not get a "maintenence prompt" it was just 
stuck at trying to mount the non-existent lvm partitions.

My sysvinit systems simply spit out an error "can mount what ever blah 
blah blah" and continued to boot. Of course those points were not 
mounted by the system did boot fully.

As for booting without an fstab I do that alot on my custom "rescue" usb 
thumb drives as they do not have a fstab file at all.
I use not *.mount files at all and the system works just fine....the 
kernel knows where its root file system is.
Try removing/moving the fstab from a test system.  It will boot and run 
fine, of course you will lose swap and any other such things but if you 
have everything on one partition your good.