Ekaanbj: /* change value of virtual machine */

2026-02-13T09:23:40Z

change value of virtual machine

← Older revision		Revision as of 09:23, 13 February 2026
Line 106:		Line 106:
	virsh dumpxml fedora_20_raid1 \| less		virsh dumpxml fedora_20_raid1 \| less
	=change value of virtual machine=		=change value of virtual machine=
	virsh autostart ~~virtual_machine_name~~		virsh autostart <vm-name>
			virsh autostart <vm-name> --disable

	=disk handling=		=disk handling=

Ekaanbj: /* create a vmw with spice */

2026-01-02T19:29:51Z

create a vmw with spice

← Older revision		Revision as of 19:29, 2 January 2026
Line 281:		Line 281:
	This time with a qcow2 disk		This time with a qcow2 disk
	qemu-system-x86_64 -m 2048 -enable-kvm -cpu host -smp 2 -cdrom veeam-recovery-media-6.3.0.73_x86_64.iso -boot d -vga qxl -spice port=5900,addr=0.0.0.0,disable-ticketing=on -device virtio-serial-pci -chardev spicevmc,id=vdagent,name=vdagent -device virtserialport,chardev=vdagent,name=com.redhat.spice.0 -display none -drive file=veeam.qcow2,format=qcow2,if=virtio		qemu-system-x86_64 -m 2048 -enable-kvm -cpu host -smp 2 -cdrom veeam-recovery-media-6.3.0.73_x86_64.iso -boot d -vga qxl -spice port=5900,addr=0.0.0.0,disable-ticketing=on -device virtio-serial-pci -chardev spicevmc,id=vdagent,name=vdagent -device virtserialport,chardev=vdagent,name=com.redhat.spice.0 -display none -drive file=veeam.qcow2,format=qcow2,if=virtio
			=Start vm with disk passthrough. Booting via cdrom=
			qemu-system-x86_64 -enable-kvm -m 4G -smp 2 \
			-drive file=/dev/sda,format=raw,cache=none,if=virtio -cdrom ubuntu-24.04.3-desktop-amd64.iso -boot d -vga virtio -display gtk

	=Start cloudos vm with nvme disk=		=Start cloudos vm with nvme disk=
	# meta-data		# meta-data

Ekaanbj: /* ip address */

2025-12-24T09:27:44Z

ip address

← Older revision		Revision as of 09:27, 24 December 2025
Line 205:		Line 205:
	virsh net-dhcp-leases default		virsh net-dhcp-leases default
	=ip address=		=ip address=
	~~Which ip does vm have~~		# QEMU guest agent
	virsh domifaddr ~~<vm>~~		virsh domifaddr crash-test-dummy --source agent
	~~==Get ip from vm==~~		# Network ARP table
	~~nmap -sn -n 10.111.222.* >/dev/null ; for VM in master1 master2 master3 worker1 worker2 worker3 ; do echo $VM $( export VM=$VM ; MAC=$(~~virsh ~~domiflist $VM \| grep~~ -~~oE '([0~~-9A-Fa-~~f]{2}[:-]){5}([0-9A-Fa-f]{2})') ;~~ arp ~~-a \| grep $MAC \| grep -oE '[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}' ) ; done~~		virsh domifaddr crash-test-dummy --source arp
	~~export NETWORK='10.111.222.*' ; nmap -sn -n "${NETWORK}" >/dev/null ; for VM in $(~~virsh ~~list \| tail -n +3 \| awk '{print $2}') ; do echo $VM $( export VM=$VM ; MAC=$(virsh domiflist $VM \| grep -oE '([0-9A-Fa-f]{2}[:-]){5}([0-9A-Fa-f]{2})') ; arp -a \| grep $MAC \| grep -oE '[0~~-~~9]{1,3}\.[0~~-~~9]{1,3}\.[0~~-~~9]{1,3}\.[0~~-~~9]{1,3}' ) ; done~~		# Libvirt DHCP leases
			virsh domifaddr crash-test-dummy --source lease

	=stop running vm:s=		=stop running vm:s=

Ekaanbj: /* list content of pools */

2025-10-08T18:30:09Z

list content of pools

New page

=prepare environment=
# Is environment prepared for viritutalization.
egrep '(vmx|svm)' /proc/cpuinfo
vmx - (intel) svm - (amd)

=Create disk image.=
qemu-img create -f qcow2 fedora20.halfface.se.qcow2 50G
=info about qcow2=
qemu-img info $machine.qcow2
qemu-img info $machine.qcow2 --force-share

=mount qcow2 image=
# Create /dev/nbd devices if they do not exist.
modprobe nbd max_part=8
# Connect qcow2 file to nbd device.
qemu-nbd --connect=/dev/nbd0 ./img_output/Rocky-8.6-x86_64-dvd1/rocky8.qcow2
# Sanity check disk device.
gdisk -l /dev/nbd0
Number Start (sector) End (sector) Size Code Name
1 2048 2099199 1024.0 MiB 8300 Linux filesystem
2 2099200 41943039 19.0 GiB 8E00 Linux LVM
# List device to mount
ls -la /dev/mapper/
total 0
drwxr-xr-x 2 root root 100 2022-08-25 12:13:50 .
drwxr-xr-x 22 root root 5220 2022-08-25 12:13:50 ..
lrwxrwxrwx 1 root root 7 2022-08-25 12:13:50 vg0-root -> ../dm-1
# Mount device
mount /dev/mapper/vg0-root /mnt/

=list all domain blocks=
virsh domblklist $vm
=list info about block device=
virsh domblkstat $vm vda --human
=List short info about vm=
virsh dominfo $vm
=add ram on the fly=
virsh setmem --domain $VM --size 1500M --current

=Install software=
yum install -y qemu kvm SDL bridge-utils tunctl

=install virtual machine.=
virt-install --connect qemu:///system --name Fedora_16 --ram 2048 --vcpus=1 -f /ssd/libvirt/Fedora_16.qcow2 -s 30 -c /install/system/linux/fedora/16/Fedora-16-x86_64-netinst.iso --vnc --noautoconsole --hvm
=delete virtual machine.=
virsh undefine kvm_1
=list libvirt storage pools=
virsh pool-list --all
=list content of pools=
virsh pool-list --name | grep -v '^$' | while read POOL ; do POOL_DIR=$(virsh pool-dumpxml "${POOL}" | xmllint --format - | awk -F '<path>|</path>' '/<path>/ {print $2}') ; echo '#' "${POOL} ${POOL_DIR}" ; (cd "${POOL_DIR}/"; ls -la *.iso *.ISO *.qcow2 *.QCOW2 *.ima *.IMA *.img *.IMG 2>/dev/null ); done
=create a pool=
virsh pool-define-as fedora42 dir --target /install/system/linux/fedora/42/
virsh pool-build fedora42
virsh pool-start fedora42
virsh pool-autostart fedora42
virsh pool-list --all
virsh pool-info fedora42

=connect to virtual machine.=
virt-viewer Fedora_16
On remote machine over ssh
virt-viewer --connect qemu+ssh://root@anden.halfface.se/system win8

=convert file format=
# img to qcow2
qemu-img convert -cp -O qcow2 kvm_1.img kvm_1.qcow2
# vmdk to qcow2
qemu-img convert disk0.vmdk -O qcow2 bigbluebutton.qcow2
FILE=costest-ph9l4-rhcos.vmdk ; qemu-img convert ${FILE} -O qcow2 ${FILE%.*}.qcow2
# vhdx to qcow2
FILE=<file> ; qemu-img convert -f vhdx -O qcow2 ${FILE} ${FILE}.qcow2

=snapshot=
# Create snapshot
virsh snapshot-create SL_63
# List snapshots
virsh snapshot-list SL_63
# Delete snapshot
virsh snapshot-delete SL_63 1346734871
# Revert to snapshot
virsh snapshot-revert fedora20_2.halfface.se 1414336149
List info about qcow2 image.
qemu-img info sms-app02.qcow2 --force-share
image: sms-app02.qcow2
file format: qcow2
virtual size: 100G (107374182400 bytes)
disk size: 107G
cluster_size: 65536
Snapshot list:
ID TAG VM SIZE DATE VM CLOCK
2 snapshot1 0 2018-04-23 18:50:15 00:00:00.000
4 pre-patch 0 2018-04-24 10:34:05 00:00:00.000
Format specific information:
compat: 1.1
lazy refcounts: false
refcount bits: 16
corrupt: false
Delete snapshot
qemu-img snapshot -d 4 sms-app02.qcow2

=list information=
# Simple information about domain.
virsh dominfo fedora_20_raid1

# View information about domain.
virsh dumpxml fedora_20_raid1 | less
=change value of virtual machine=
virsh autostart virtual_machine_name

=disk handling=
# Detach one of the disks.
virsh detach-disk fedora_20_raid1 vda
virsh detach-disk rhel8.5 vda --persistent

# Attach disk
virsh attach-disk fedora_20_raid1 /ssd/libvirt/fedora20_1.qcow2 vda --sourcetype file --subdriver qcow2
virsh attach-disk host /var/lib/libvirt/images/host-#.qcow2 vdb --driver qemu --subdriver qcow2 --targetbus virtio --persistent

# Copy kvm machine.
virsh dumpxml <domain> > domain.xml
vi domain.xml
virsh create domain.xml

# Eject cdrom.
virsh change-media www.halfface.se hda --eject

=duplicate move machine=
# You cannot "clone" a running vm, stop it. suspend and destroy
# are also valid options for less graceful cloning
virsh shutdown this.vm

# copy the storage.
cp /var/lib/libvirt/images/{this-vm,that-vm}.img

# dump the xml for the original
virsh dumpxml this-vm > /tmp/that-vm.xml

# hardware addresses need to be removed, libvirt will assign
# new addresses automatically
sed -i /uuid/d /tmp/that-vm.xml
sed -i '/mac address/d' /tmp/that-vm.xml

# and actually rename the vm: (this also updates the storage path)
sed -i 's/this-vm/that-vm/g' /tmp/that-vm.xml

# finally, create the new vm
virsh define /tmp/that-vm.xml
virsh start this-vm
virsh start that-vm

=virt-convert=
Convert vmware image to kvm.
virt-convert . --disk-format qcow2 --destination .
=drivers=
Drivers for other os and enhancements.
https://www.spice-space.org/download.html
=access via spice=
remote-viewer spice://10.151.105.122:5900
=virsh capabilities=
currently supported machine types.
virsh capabilities
=extend qcow2 image=
Inspect storage
virsh domblklist almalinux8.4
Inspect storage
virsh domblkinfo almalinux8.4 /var/lib/libvirt/images/almalinux8.4.qcow2
Make storage to new size.
virsh blockresize almalinux8.4 /var/lib/libvirt/images/almalinux8.4.qcow2 64G
Inspect storage
qemu-img info almalinux8.4.qcow2 --force-share
Create partition from free space.
fdisk /dev/vda
pvcreate /dev/vda3
vgextend almalinux /dev/vda3
lvextend -l +100%FREE /dev/mapper/almalinux-root
resize2fs /dev/mapper/almalinux-root
xfs_growfs /dev/mapper/almalinux-root
=resize qcow2=
qemu-img resize Fedora-38-Silverblue.qcow2 60G

=rename vm=
virsh stop foo
virsh domrename foo bar
cd /var/lib/libvirt/images
mv foo.qcow2 bar.qcow2
# replace foo with bar
virsh edit bar

[[Category:Applications]]
[[Category:Unix]]
[[Category:Virtualization]]

=rename vm=
virsh domrename foo bar

=dhcp leases=
virsh net-list
virsh net-dhcp-leases okd01-dwb8v

List networks
virsh net-list

virsh net-info default
View leases
virsh net-dhcp-leases default
=ip address=
Which ip does vm have
virsh domifaddr <vm>
==Get ip from vm==
nmap -sn -n 10.111.222.* >/dev/null ; for VM in master1 master2 master3 worker1 worker2 worker3 ; do echo $VM $( export VM=$VM ; MAC=$(virsh domiflist $VM | grep -oE '([0-9A-Fa-f]{2}[:-]){5}([0-9A-Fa-f]{2})') ; arp -a | grep $MAC | grep -oE '[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}' ) ; done
export NETWORK='10.111.222.*' ; nmap -sn -n "${NETWORK}" >/dev/null ; for VM in $(virsh list | tail -n +3 | awk '{print $2}') ; do echo $VM $( export VM=$VM ; MAC=$(virsh domiflist $VM | grep -oE '([0-9A-Fa-f]{2}[:-]){5}([0-9A-Fa-f]{2})') ; arp -a | grep $MAC | grep -oE '[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}\.[0-9]{1,3}' ) ; done

=stop running vm:s=
virsh list --state-running --name | grep -v ^$ | while read VM ; do virsh shutdown $VM ; done

=execute command via agent=
virsh -c qemu:///system qemu-agent-command <vm> '{"execute": "guest-exec", "arguments": { "path": "/usr/bin/ls", "arg": [ "/" ], "capture-output": true }}'
virsh -c qemu:///system qemu-agent-command <vm> '{"execute": "guest-exec-status", "arguments": { "pid": <pid> }}'
base64 -d on output.
==all in one==
export KVM=pm-app02 ; KVM_PID=$(virsh -c qemu:///system qemu-agent-command ${KVM} '{"execute": "guest-exec", "arguments": { "path": "id", "arg": [ "-a","-a" ], "capture-output": true }}' --pretty | jq -r .return.pid) ; virsh -c qemu:///system qemu-agent-command "${KVM}" "{\"execute\": \"guest-exec-status\", \"arguments\": { \"pid\": ${KVM_PID} }}" | jq -r '.return."out-data"' | base64 -d

=virsh console <vm>=
Connect to vm serial
virsh console <vm>
=enable console login=
systemctl enable --now serial-getty@ttyS0.service

=socat console=
VM=terraform_test ; sudo socat -,echo=0 $(virsh dumpxml $VM | xq | grep "console type" | awk -F\" '{print $4}')

=set password on user=
virsh set-user-password <vm> root password
=Which version of libvirtd=
virsh -c qemu+ssh://root@hdplex.halfface.se/system version
=send keyboard to vm=
https://libvirt.org/manpages/virkeycode-xtkbd.html
virsh send-key terraform_vm --codeset linux KEY_LEFTALT KEY_TAB KEY_TAB

=nested virualization and virt-install=
<pre>
# Enable nested virtualization.
cat <<'EOF' > /etc/modprobe.d/kvm.conf
options kvm_amd nested=1
options kvm ignore_msrs=1 report_ignored_msrs=0
EOF
# Install dependecies.
systemctl enable autofs --now ; ln -s /net/10.111.222.1/storage/install /install ; ln -s /net/10.111.222.1/storage/temp /temp
dnf install -y virt-install libvirt qemu-kvm git stow vim-enhanced
systemctl enable libvirtd --now
# Setup cloud-os
cp /install/system/linux/fedora/40/Fedora-Cloud-Base-Generic.x86_64-40-1.14.qcow2 /var/lib/libvirt/images/fedora-cloud-base-generic.qcow2
qemu-img info /var/lib/libvirt/images/fedora-cloud-base-generic.qcow2
qemu-img resize /var/lib/libvirt/images/fedora-cloud-base-generic.qcow2 +195G
virt-install --name fedora-cloud-base-generic \
--cpu host-passthrough,cache.mode=passthrough \
--memory 19456 --vcpus 10 --graphics none\
--os-variant centos-stream9\
--import \
--disk /var/lib/libvirt/images/fedora-cloud-base-generic.qcow2,format=qcow2,bus=virtio \
--network bridge=br0,model=virtio \
--cloud-init \
--console pty,target_type=serial
# Setup Fedora Server.
cp /install/system/linux/fedora/40/Fedora-Server-KVM-40-1.14.x86_64.qcow2 /var/lib/libvirt/images/fedora-server-kvm.qcow2
qemu-img info /var/lib/libvirt/images/fedora-server-kvm.qcow2
qemu-img resize /var/lib/libvirt/images/fedora-server-kvm.qcow2 +195G
virt-install --name fedora-server-kvm \
--cpu host-passthrough,cache.mode=passthrough \
--memory 19456 --vcpus 10 --graphics none\
--os-variant centos-stream9\
--import \
--disk /var/lib/libvirt/images/fedora-server-kvm.qcow2,format=qcow2,bus=virtio \
--network bridge=br0,model=virtio \
--cloud-init \
--console pty,target_type=serial
</pre>
=create a vmw with spice=
qemu-system-x86_64 -m 2048 -enable-kvm -cpu host -smp 2 -cdrom systemrescue-11.03-amd64.iso -boot d -vga qxl -spice port=5900,addr=0.0.0.0,disable-ticketing=on -device virtio-serial-pci -chardev spicevmc,id=vdagent,name=vdagent -device virtserialport,chardev=vdagent,name=com.redhat.spice.0 -display none
This time with a qcow2 disk
qemu-system-x86_64 -m 2048 -enable-kvm -cpu host -smp 2 -cdrom veeam-recovery-media-6.3.0.73_x86_64.iso -boot d -vga qxl -spice port=5900,addr=0.0.0.0,disable-ticketing=on -device virtio-serial-pci -chardev spicevmc,id=vdagent,name=vdagent -device virtserialport,chardev=vdagent,name=com.redhat.spice.0 -display none -drive file=veeam.qcow2,format=qcow2,if=virtio
=Start cloudos vm with nvme disk=
# meta-data
instance-id: fedora-cloud-01
local-hostname: fedora-cloud
# user-data
#cloud-config
users:
- name: fedora
sudo: ALL=(ALL) NOPASSWD:ALL
ssh-authorized-keys:
- ssh-ed25519 AAAAC3NzaC1lZDI1NTE5AAAAIPWQhPFFJYj6j+uPGCTuuNqy/WG5QTBZ1L05UdZwNtC8 andreas.bjorklund@binero.com
lock_passwd: false
plain_text_passwd: 'password'
chpasswd:
expire: false
# build cloud init image.
genisoimage -output seed.iso -volid cidata -joliet -rock user-data meta-data
# Cread nvme machine.
qemu-system-x86_64 \
-machine q35,accel=kvm \
-bios /usr/share/OVMF/OVMF_CODE.fd \
-drive file=Fedora-Cloud-Base-Generic-42-1.1.x86_64.qcow2,format=qcow2,if=none,id=drive0 \
-device nvme,drive=drive0,serial=deadbeef,bootindex=1 \
-drive file=seed.iso,format=raw,if=none,id=seed \
-device virtio-blk-pci,drive=seed,bootindex=2 \
-device virtio-net-pci,netdev=net0 \
-netdev user,id=net0,hostfwd=tcp::2222-:22 \
-m 2G \
-cpu host \
-nographic
=list os-variant=
osinfo-query os
[[Category:Applications]]
[[Category:Unix]]
[[Category:Virtualization]]

Kvm - Revision history

Ekaanbj: /* change value of virtual machine */

Ekaanbj: /* create a vmw with spice */

Ekaanbj: /* ip address */

Ekaanbj: /* list content of pools */