dracut vs. genkernel

[Stefan G. Weichinger]

Greets, gentoo-users ...

I am currently trying to find out why my LVM2-volumes aren't activated
correctly at boot time. I am using packages from the overlay
systemd-love as I run systemd as init-system (why? that's another
discussion ;-) ).

Until now I always was kind of lazy and used genkernel (or lately
"genkernel-next") to build and install my kernels/modules. Yes, it's
uncool, but so far it worked for me and it was comfortable.

In my discussion with one of the devs of the systemd-love-overlay he
pointed me at dracut to generate my initramfs. Never used it before and
so I am still learning (yes, it booted already).

I found infos in the Gentoo Wiki but I would also hear your opinions and
experience:

How do you generate your kernel and initramfs with dracut? Any handy
scripts available ... any tricks or hints?

Where are the advantages of dracut compared to genkernel? The udev-approach?

Thanks, Stefan

[Stefan G. Weichinger]

Post by Stefan G. Weichinger
How do you generate your kernel and initramfs with dracut? Any handy
scripts available ... any tricks or hints?

Additional fact here:

I boot with grub2 ... so I need to have an initramfs generated that is
detected by grub2-mkconfig. For now I simply let it use the name of the
genkernel-initramfs ... how do you handle this?

Stefan

[Canek Peláez Valdés]

Post by Stefan G. Weichinger

Post by Stefan G. Weichinger
How do you generate your kernel and initramfs with dracut? Any handy
scripts available ... any tricks or hints?

I boot with grub2 ... so I need to have an initramfs generated that is
detected by grub2-mkconfig. For now I simply let it use the name of the
genkernel-initramfs ... how do you handle this?

I use this script to generate my initramfs:

--------------------------------------------------------------------------------
#!/bin/sh

KVER=$(readlink /usr/src/linux | sed "s/^linux-//g")

echo "Creating initrd for kernel version ${KVER}..."

FIRMWARE=""

for i in $(find /lib64/firmware -type f); do
FIRMWARE+=" ${i}"
done

/usr/bin/dracut -f -H -I "${FIRMWARE}" /boot/initrd-${KVER} ${KVER}
--------------------------------------------------------------------------------

I use this command to generate my GRUB2 config:

grub2-mkconfig -o /boot/grub2/grub.cfg

Everything just works. However, I don't use LVM, and I don't use the
systemd-love overlay.

Regards.
--
Canek Peláez Valdés
Posgrado en Ciencia e Ingeniería de la Computación
Universidad Nacional Autónoma de México

[Stefan G. Weichinger]

Post by Canek Peláez Valdés
--------------------------------------------------------------------------------
#!/bin/sh
KVER=$(readlink /usr/src/linux | sed "s/^linux-//g")
echo "Creating initrd for kernel version ${KVER}..."
FIRMWARE=""
for i in $(find /lib64/firmware -type f); do
FIRMWARE+=" ${i}"
done
/usr/bin/dracut -f -H -I "${FIRMWARE}" /boot/initrd-${KVER} ${KVER}
--------------------------------------------------------------------------------
grub2-mkconfig -o /boot/grub2/grub.cfg
Everything just works. However, I don't use LVM, and I don't use the
systemd-love overlay.

Nice script, thanks!

I will have to adapt it a bit to be able to use it with

linux -> /usr/src/linux-git ....

But for stuff like gentoo-sources it just works, yes!

Stefan

[Stefan G. Weichinger]

Post by Stefan G. Weichinger
I will have to adapt it a bit to be able to use it with
linux -> /usr/src/linux-git ....

I hacked something ... can't share right now as I shamelessly used
function from genkernel to read in the kernel version ;-)

S

[Michael Hampicke]

Post by Stefan G. Weichinger
I am currently trying to find out why my LVM2-volumes aren't activated
correctly at boot time. I am using packages from the overlay
systemd-love as I run systemd as init-system (why? that's another
discussion ;-) ).

When you find a solution, I'd be interested :) Having the same problem,
also running grub2, systemd, lvm.

This is my current work-around

$ cat /etc/systemd/system/lvm.service
[Unit]
Description=Load LVM

[Service]
Type=oneshot
ExecStart=/sbin/pvscan
ExecStart=/sbin/vgscan --mknodes
ExecStart=/sbin/vgchange --sysinit -a ly
ExecStart=/usr/bin/sleep 1
ExecStart=/bin/mount -o noatime /dev/vg1/a /mnt/a
ExecStart=/bin/mount -o noatime /dev/vg1/b /mnt/b

[Install]
WantedBy=multi-user.target

[Stefan G. Weichinger]

Post by Michael Hampicke
This is my current work-around
$ cat /etc/systemd/system/lvm.service [Unit] Description=Load LVM
[Service] Type=oneshot ExecStart=/sbin/pvscan
ExecStart=/sbin/vgscan --mknodes ExecStart=/sbin/vgchange --sysinit
-a ly ExecStart=/usr/bin/sleep 1 ExecStart=/bin/mount -o noatime
/dev/vg1/a /mnt/a ExecStart=/bin/mount -o noatime /dev/vg1/b
/mnt/b
[Install] WantedBy=multi-user.target

Yes, looks like a workaround ;-)

I will check back if I find something ...

S