lvm Archives - Heiko's Blog

QEMU 7.2 and Raw Disks

Update January 27, 2023: The issue described below is limited to users of RAW partitions. But there is a workaround. See under “What to do?”

A recent update from QEMU 7.1 to QEMU 7.2 caused my Windows 10 VM to show 100% utilization of the C: drive. Performance of the Windows VM dropped to the bottom – the VM was pretty much unusable.

Users at the VFIO Reddit reported similar issues. However, as it turned out, it seems to affect only storage on LVM raw volumes. In other words, if you have your VM in a qcow file, all should be well.

New NTFS Driver in Kernel 5.15

Linux kernel release 5.15 introduced a new NTFS file system driver named NTFS3. This kernel driver was originally developed by Paragon Software as a commercial solution (more about the ntfs3 driver can be found on their FAQ page).

NTFS3 is not to be confused with NTFS-3G, a user space driver that employs the FUSE or “file system in user space” approach. There is a 3rd driver available – simply NTFS – that was shipped as the standard NTFS driver on Linux, but it lacked support for many of the Microsoft NTFS features (like writing to disk). Most of us dealing with NTFS drives have installed and use the NTFS-3G driver.

LVM and the Ease of Migrating to a New Drive

Online data relocation to other drives using LVM and pvmove

These days my disks are filling up fast. My current PC holds 7 drives, including 2 NVMe drives. Actually 8 drives as I installed a new HDD today. All of my disks and partitions – with the notable exception of the FAT16 EFI partition for UEFI boot – are using LVM, the Logical Volume Manager.

With the availability of larger drives at reasonable costs, I decided to move some logical volumes (LV) spanning several drives onto one single drive, thus consolidating disks. This one drive will then be mirrored in a RAID-1 configuration for redundancy.

Note: In a multi-drive LVM Logical Volume each drive represents a potential point of failure. Moving the data from multiple drives onto one drive reduces that risk.

Remote Backup Script for Windows NTFS Partitions on LVM Volumes

Linux bash script to mount and backup / synchronize a Windows 10 partition inside a LVM volume to a remote backup server using rsync and SSH

I run the bash script below to backup my Windows NTFS partitions residing on LVM volumes to a remote backup server. It uses SSH and public key authentication to authenticate at the remote side.

The script mounts an NTFS partition inside a LVM raw volume. It performs a file-based backup using rsync. It is NOT suitable for system backups!

Please carefully read the “Requirements”, “How it Works”, and “Usage” sections before attempting to use it.