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How to determine LVM mapping on a physical device?
How do I determine LVM mapping on a physical device? I have a server (SUSE 11.5) that has two disks. There is only one volume group (vg01). How do I determine the physical device on which that vg exists? shows you the physical device (s) corresponding to all your volume groups. This is the only one of my VGs that corresponds to a raw partition.
Which is the end result of LVM technology?
From the chart above, you can see that LVM technology ends at creating a Logical Volume (LV). A physical volume must be created, followed by a volume group, and lastly, a logical volume. The Physical Volume and Volume group are just one of the processes that must be followed to create the end result, which is the Logical Volume.
What does Logical Volume Manager ( LVM ) stand for?
General concepts of logical volume manager (LVM) goes to the long gone era of 40MB drives (Not 40GB, just forty megabytes) which created a legitimate desire to create filesystems that span several physical disks. Another driver was the desire to have a capability to change size of existing partitions of the fly.
Can you add more than one volume in LVM?
With LVM, multiple volumes can be easily added. You can add more than 250 volumes but with a standard partition, you can’t add up to 50 partitions. Physical volume (s) are created from block devices. A block device could be LUNS created from the storage array, the physical hard drive or even a partition on a disk.
How can I find out if my DM is a multipathed device?
You can use the dmsetup command to find out which device mapper entries match the multipathed devices. The following command displays all the device mapper devices and their major and minor numbers. The minor numbers determine the name of the dm device. For example, a minor number of 3 corresponds to the multipathed device /dev/dm-3 .
How does LVM find drives after setup in Linux?
By default, LVM (specifically vgscan, invoked from an init script) scans all likely-looking block devices at boot time. You can define filters in /etc/lvm.conf. As long as you don’t define restrictive filters, it doesn’t matter how you connect your drives.
How to determine the name of a dm device?
The minor numbers determine the name of the dm device. For example, a minor number of 3 corresponds to the multipathed device /dev/dm-3 . 5.10. Multipath Command Options