Ubuntu 20.04
Sponsored Link

KVM : Management tools2020/06/02

 
Install useful tools for virtual machine management.
[1] Install required packages.
root@dlp:~#
apt -y install libguestfs-tools virt-top
[2] Get official OS image and Create a Virtual Machine.
( If you'd like to do from OS installation, refer to here of [1] )
# display available OS template

root@dlp:~#
virt-builder -l

.....
.....
ubuntu-10.04             x86_64     Ubuntu 10.04 (Lucid)
ubuntu-12.04             x86_64     Ubuntu 12.04 (Precise)
ubuntu-14.04             x86_64     Ubuntu 14.04 (Trusty)
ubuntu-16.04             x86_64     Ubuntu 16.04 (Xenial)
ubuntu-18.04             x86_64     Ubuntu 18.04 (bionic)
ubuntu-20.04             x86_64     Ubuntu 20.04 (focal)
.....
.....

# create Ubuntu 18.04 VM image

root@dlp:~#
virt-builder ubuntu-18.04 --format qcow2 --size 10G -o /var/kvm/images/ubuntu1804.qcow2 --root-password password:myrootpassword

[   6.1] Downloading: http://builder.libguestfs.org/ubuntu-18.04.xz
[ 111.2] Planning how to build this image
[ 111.2] Uncompressing
[ 116.2] Resizing (using virt-resize) to expand the disk to 10.0G

.....
.....

                   Output file: /var/kvm/images/ubuntu1804.qcow2
                   Output size: 10.0G
                 Output format: qcow2
            Total usable space: 9.8G
                    Free space: 8.3G (84%)


# to configure VM with the image above, run virt-install
root@dlp:~# virt-install \
--name ubuntu-18.04 \
--ram 4096 \
--disk path=/var/kvm/images/ubuntu1804.qcow2 \
--vcpus 2 \
--os-variant ubuntu18.04 \
--network bridge=br0 \
--graphics none \
--noautoconsole \
--boot hd \
--noreboot \
--import 

Starting install...
Domain creation completed.
You can restart your domain by running:
  virsh --connect qemu:///system start ubuntu-18.04
[3] [ls] a directory in a virtual machine.
root@dlp:~#
virt-ls -l -d ubuntu2004 /root

total 16
drwx------  2 0 0 4096 Jun  2 02:14 .
drwxr-xr-x 19 0 0 4096 Jun  2 02:24 ..
-rw-r--r--  1 0 0 3106 Dec  5 14:39 .bashrc
-rw-r--r--  1 0 0  161 Dec  5 14:39 .profile
[4] [cat] a file in a virtual machine.
root@dlp:~#
virt-cat -d ubuntu2004 /etc/passwd

root:x:0:0:root:/root:/bin/bash
daemon:x:1:1:daemon:/usr/sbin:/usr/sbin/nologin
bin:x:2:2:bin:/bin:/usr/sbin/nologin
sys:x:3:3:sys:/dev:/usr/sbin/nologin
sync:x:4:65534:sync:/bin:/bin/sync
...
...
[5] Edit a file in a virtual machine.
root@dlp:~#
virt-edit -d ubuntu2004 /etc/fstab


# /etc/fstab: static file system information.
#
# Use 'blkid' to print the universally unique identifier for a
# device; this may be used with UUID= as a more robust way to name devices
# that works even if disks are added and removed. See fstab(5).
#
# <file system> <mount point>   <type>  <options>       <dump>  <pass>
/dev/mapper/vgubuntu-root /               ext4    errors=remount-ro 0       1
# /boot/efi was on /dev/vda1 during installation
UUID=54D9-A80A  /boot/efi       vfat    umask=0077      0       1
/dev/mapper/vgubuntu-swap_1 none            swap    sw              0       0
[6] Display disk usage in a virtual machine.
root@dlp:~#
virt-df -d ubuntu2004

Filesystem                           1K-blocks       Used  Available  Use%
ubuntu2004:/dev/sda1                    523248          4     523244    1%
ubuntu2004:/dev/vgubuntu/root         18971044    2095356   15888964   12%
[7] Mount a disk for a virtual machine.
root@dlp:~#
guestmount -d ubuntu2004 -i /mnt

root@dlp:~#
ll /mnt

total 88
drwxr-xr-x 19 root root  4096 Jun  1 20:24 ./
drwxr-xr-x 20 root root  4096 Jun  1 19:34 ../
lrwxrwxrwx  1 root root     7 Jun  1 20:14 bin -> usr/bin/
drwxr-xr-x  4 root root  4096 Jun  1 20:28 boot/
drwxr-xr-x  4 root root  4096 Jun  1 20:14 dev/
...
...
[8] Display the status of virtual machines.
root@dlp:~#
virt-top

virt-top 21:59:37 - x86_64 8/8CPU 2593MHz 11978MB
2 domains, 1 active, 1 running, 0 sleeping, 0 paused, 1 inactive D:0 O:0 X:0
CPU: 0.0%  Mem: 6144 MB (6144 MB by guests)

   ID S RDRQ WRRQ RXBY TXBY %CPU %MEM    TIME   NAME
    1 R                      0.0  0.0  38:11.38 win2k19
    -                                           (ubuntu2004)
Matched Content