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DRBD LVM - Lower device is already claimed

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Taken from here

This is put here for my reference, in case the above link ever breaks.

When you use a DRBD device as an underlying block device for lvm as described in the drbd manual you may face the following error after reboot and start DRBD. Lower device is already claimed The reason is the lack of the lvm.conf in the initramfs. To add this file to the initramfs simply follow these steps: edit the file


/usr/share/initramfs-tools/hooks/lvm2 

and add

[ -r /etc/lvm/lvm.conf ] && mkdir $DESTDIR/etc/lvm && cp /etc/lvm/lvm.conf $DESTDIR/etc/lvm 

after the lines contains

cp -p /etc/udev/rules.d/85-lvm2.rules ${DESTDIR}/etc/udev/rules.d

so that it looks like

cp -p /etc/udev/rules.d/85-lvm2.rules ${DESTDIR}/etc/udev/rules.d
[ -r /etc/lvm/lvm.conf ] && mkdir $DESTDIR/etc/lvm && cp /etc/lvm/lvm.conf $DESTDIR/etc/lvm

then you have to rebuild the initramfs using

update-initramfs -u

and to restart the system in order to modifications can take effect

reboot

Now DRBD should start as wanted, assuming you had modified the lvm.conf as mentioned in the link.

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