Check out my first novel, midnight's simulacra!

KVM: Difference between revisions

From dankwiki
(Created page with 'The [http://www.linux-kvm.org/page/Main_Page www.linux-kvm.org] page is really nice. The [http://calamari.reverse-dns.net:980/cgi-bin/moin.cgi/FrontPage qemu wiki] also regularly...')
 
No edit summary
 
(One intermediate revision by the same user not shown)
Line 1: Line 1:
The [http://www.linux-kvm.org/page/Main_Page www.linux-kvm.org] page is really nice. The [http://calamari.reverse-dns.net:980/cgi-bin/moin.cgi/FrontPage qemu wiki] also regularly proves itself useful.
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 [http://www.linux-kvm.org/page/Main_Page www.linux-kvm.org] page is really nice. The [http://calamari.reverse-dns.net:980/cgi-bin/moin.cgi/FrontPage qemu wiki] also regularly proves itself useful.
 
==Mounting a QCOW2 image==
* Verify qcow2 format:
<pre>[schwarzgerat](130) $ file  /media/vms/win10.img
/media/vms/win10.img: QEMU QCOW2 Image (v3), 137438953472 bytes
[schwarzgerat](0) $ </pre>
* Connect it to a network block device:
<pre>[schwarzgerat](1) $ sudo qemu-nbd --connect=/dev/nbd0 /media/vms/win10.img
[schwarzgerat](0) $</pre>
* Find the partition:
<pre>[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) $</pre>
* Mount it: <tt>sudo mount /dev/nbd0p4 /media/windows</tt>


==Integration with virtio==
==Integration with virtio==

Latest revision as of 17:10, 5 September 2022

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

Integration with virtio

Tmpfs issues

  • See the info on hugetlbfs at Pages

Automated/daemonized use