Pvcreate on file

The number of stripes cannot be greater than the number of physical volumes in the volume group. The -I denotes the strip size. The above command creates a striped logical volume across 2 physical volumes with a stripe of 64kB. A mirror maintains identical copies of data on different devices. When data is written to one device, it is written to a second device as well. This provides protection for device failures. When one leg of a mirror fails, the logical volume becomes a linear volume and can still be accessed.

LVM maintains a small log which it uses to keep track of which regions are in sync with the mirror. This log can be kept on disk, which will keep it persistent across reboots, or it can be maintained in memory.

The following command will create a mirrored logical volume. The Logical Volumes can be made known to the kernel using the command lvchange. After rebooting the system or running vgchange -an, you will not be able to access your VGs and LVs. To reactivate the volume group, run The -a option is used to activate or deactivate the Logical Volume.

Using y with -a option will make it known to kernel and n will make it unavailable. So only run this command based on specific requirement. Indicate the LV to activate. More physical volumes can be added to an existing volume group thus increasing its size. Learn more. Does pvcreate destroy all the data in a partition? Ask Question.

Asked 2 years, 10 months ago. Active 2 years, 10 months ago. Viewed 1k times. Improve this question. Tim Tim 1. What do you mean by "mark the disk as a PV"? Formatting an existing device as a PV will effectively lose said data in the same way that reformating a filesystem with a new filesystem will lose previous files. What do you mean? Marking a device as a PV is not reformating a filesystem with a new filesystem. Both involve removing the structure of a volume and replacing it with a new structure.

You don't make a physical volume by "marking" it as such in the same way you don't make a filesystem by "marking" it - it needs formatting — Torin. This may effectively make the data structures eg the filesystem superblock unreadable, but the underlying data may be recoverable by a data recovery tool, or by dd. From a typical end-user perspective, doing pvcreate on a block device may render the existing filesystem unreadable. Add a comment. Active Oldest Votes.

Does it say that pvcreate will destroy all the data on a disk, No, I read all the quotes in your question, and it does not say this. The size you specify may get rounded. You should also specify an appropriate PhysicalExtentSize when creating the Volume Group with vgcreate.

Currently this can be 0, 1 or 2. If set to 2, two copies of the volume group metadata are held on the PV, one at the front of the PV and one at the end.

If set to 1 the default , one copy is kept at the front of the PV starting in the 5th sector. But if you do this and then later use vgsplit you must ensure that each VG is still going to have a suitable number of copies of the metadata after the split! Use with care. See also vgconvert 8. Force the creation without any confirmation.