KVM

KVM, a drop-in qemu replacement engine making use of VT hardware, is in my mind the best of some 4000 Linux VT Solutions. The www.linux-kvm.org page is really nice. The qemu wiki also regularly proves itself useful.

Mounting a QCOW2 image

• Verify qcow2 format:

[schwarzgerat](130) $ file  /media/vms/win10.img 
/media/vms/win10.img: QEMU QCOW2 Image (v3), 137438953472 bytes
[schwarzgerat](0) $ 

• Connect it to a network block device:

[schwarzgerat](1) $ sudo qemu-nbd --connect=/dev/nbd0 /media/vms/win10.img 
[schwarzgerat](0) $

• Find the partition:

[schwarzgerat](1) $ sudo gdisk /dev/nbd0 -l
GPT fdisk (gdisk) version 1.0.9

The protective MBR's 0xEE partition is oversized! Auto-repairing.

Partition table scan:
  MBR: protective
  BSD: not present
  APM: not present
  GPT: present

Found valid GPT with protective MBR; using GPT.
Disk /dev/nbd0: 268435456 sectors, 128.0 GiB
Sector size (logical/physical): 512/512 bytes
Disk identifier (GUID): DBEAA70E-0076-4A74-A7C4-D2F498223CD0
Partition table holds up to 128 entries
Main partition table begins at sector 2 and ends at sector 33
First usable sector is 34, last usable sector is 125829086
Partitions will be aligned on 2048-sector boundaries
Total free space is 6077 sectors (3.0 MiB)

Number  Start (sector)    End (sector)  Size       Code  Name
   1            2048         1023999   499.0 MiB   2700  Basic data partition
   2         1024000         1226751   99.0 MiB    EF00  EFI system partition
   3         1226752         1259519   16.0 MiB    0C01  Microsoft reserved ...
   4         1259520       125825023   59.4 GiB    0700  Basic data partition
[schwarzgerat](0) $

• Mount it: sudo mount /dev/nbd0p4 /media/windows

Tmpfs issues

• See the info on hugetlbfs at Pages