2.4. Multipath Devices in Logical Volumes
/dev/mapper/mpathais the name of a multipath device, the following command will mark
/dev/mapper/mpathaas a physical volume.
pvcreatecommand will fail. Note that the Anaconda and Kickstart installation programs create empty partition tables if you do not specify otherwise for every block device. If you wish to use the whole device rather than a partition, you must remove the existing partitions from the device. You can remove existing partitions with the
kpartx -dand the
fdiskcommands. If your system has block devices that are greater that 2Tb, you can use the
partedcommand to remove partitions.
/etc/lvm/lvm.conffile to exclude the disks that underlie the multipath devices. This is because if the array automatically changes the active path to the passive path when it receives I/O, multipath will failover and failback whenever LVM scans the passive path if these devices are not filtered. For active/passive arrays that require a command to make the passive path active, LVM prints a warning message when this occurs.
lvm.conf), include the following filter in the
devicessection of the file.
filter = [ "r/block/", "r/disk/", "r/sd.*/", "a/.*/" ]