The Problem
pvcreate command fails while using multipath device with below error even when the device is present.
# fdisk -l /dev/mapper/mpatha Disk /dev/mapper/mpatha: 51.6 GB, 51624542208 bytes, 100829184 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk label type: dos Disk identifier: 0x5d7fc634 Device Boot Start End Blocks Id System /dev/mapper/mpatha1 32 100829183 50414576 83 Linux
# pvcreate /dev/mapper/mpatha Device /dev/mapper/mpatha not found (or ignored by filtering).
The error usually occurs either when /etc/lvm/lvm.conf has wrong filter section or the device which is trying to be used as a PV already has an underlying Partition. Use either of the solutions described below depending on the situation you have.
Solution 1 : Verify filter settings in /etc/lvm/lvm.conf
1. Verify filter settings in /etc/lvm/lvm.conf and ensure it allows to scan multipath devices. A system with LVM devices on local SCSI storage and device-mapper-multipath SAN storage might define:
# cat /etc/lvm/lvm.conf filter = [ "a|^/dev/sda[1-9]$|", "a|^/dev/mapper/*|", "r|^/dev/*|" ]
2. Use the multipath device /dev/mapper/mpatha and pvcreate on multipath device.
# pvcreate /dev/mapper/mpatha Physical volume "/dev/mapper/mpatha" successfully created
Solution 2 : delete existing partitions if any
A second solution is to actually verify if the device which is trying to be used as a PV does not hold any underlying partitions. In the below case, the multipath disk mpatha has a partition mpatha1 as shown below.
# fdisk -l /dev/mapper/mpatha Disk /dev/mapper/mpatha: 51.6 GB, 51624542208 bytes, 100829184 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk label type: dos Disk identifier: 0x5d7fc634 Device Boot Start End Blocks Id System /dev/mapper/mpatha1 32 100829183 50414576 83 Linux <------------
As described please delete any underlying partition on device which is trying to be as a PV by issuing fdisk command afterwards please re-try pvcreate.
# fdisk /dev/mapper/mpatha Disk /dev/mapper/mpatha: 51.6 GB, 51624542208 bytes, 100829184 sectors Units = sectors of 1 * 512 = 512 bytes Sector size (logical/physical): 512 bytes / 512 bytes I/O size (minimum/optimal): 512 bytes / 512 bytes Disk label type: dos Disk identifier: 0x5d7fc634 Device Boot Start End Blocks Id System /dev/mapper/mpatha1 32 100829183 50414576 83 Linux Command (m for help): d Partition number (1-4): 1 Command (m for help): w
# pvcreate /dev/mapper/mpatha Physical volume "/dev/mapper/mpatha" successfully created