[systemd-devel] Problems with rootfs over nfs

[Kay Sievers]

On Sun, May 15, 2011 at 18:03, Mariusz Bialonczyk <manio at skyboo.net> wrote:
> On 05/15/2011 04:16 PM, Kay Sievers wrote:
>> What's in fstab for /? Maybe just that needs a fix for mount(8) to
>> understand what we do here.
> I have the following line for rootfs in fstab:
> /dev/nfs        /               nfs     defaults        0       0

Hmm, you sure, you shouldn't put the:
  server:/path
notation in here, instead of a non-existing fake device from the kernel?

>> Just a first quick check of an issue we ran into with ATA disks:
>> what's in /proc/sys/kernel/hotplug before you shut down? Or what's
>> CONFIG_UEVENT_HELPER in your kernel setup, it must be ="" on modern
>> systems, otherwise the kernel will they to exec() binaries all the
>> time and keep the system's rootfs busy.
> $ cat /proc/sys/kernel/hotplug
> /sbin/hotplug
> $ cat /usr/src/linux/.config|grep UEVENT
> CONFIG_UEVENT_HELPER_PATH="/sbin/hotplug"
>
> if it's matter - i don't have any disk - it's diskless host

Doesn't matter, it needs to be fixed. The kernel itself keeps the
mount busy, and prevents a clean shutdown.

Not sure if that's your exact problem, but having /sbin/hotplug active
today just asks for trouble, even when the binary does not exist. Just
fix the kernel config, it will also save you many hundred absolutely
useless fork()s at bootup.

Kay