File persistent_policy.conf of Package dracut

# When dracut generates the initramfs, it must refer to disks and partitions to
# be mounted in a persistent manner, to make sure the system will boot
# correctly. By default, dracut uses /dev/mapper device names.
# For example, when dracut detects multipath devices, it will use the DM-MP
# device names such as
#
# /dev/mapper/3600a098000aad73f00000a3f5a275dc8-part1
#
# This is good if the system always runs in multipath mode. But if the system is
# started without multipathing, booting with such an initramfs will fail,
# because the /dev/mapper devices will not exist. The same problem can happen
# with multipath maps and cloned SAN LUNs.
#
# To prevent this from happening, the dracut policy for addressing disks
# and partitions is changed to use /dev/disk/by-uuid device names on all
# architectures except s390/s390x, which must be by-path (bsc#915218).
persistent_policy="by-uuid"