View source for Kvm

=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

=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>
=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
[[Category:Applications]]
[[Category:Unix]]
[[Category:Virtualization]]