Libvirt
https://libvirt.org/news.html
v3.10.0 (unreleased)
qemu: Add vmcoreinfo feature
Starting with QEMU 2.11, the guest can save kernel debug details when this feature is enabled and the kernel supports it.
3.9.0 (2017-11-02) - Debian 10 buster / sid
v3.8.0 (2017-10-04)
v3.7.0 (2017-09-04)
bhyve: Support autoport for VNC ports
qemu: Added support for setting heads of virtio GPU
v3.6.0 (2017-08-02) - Ubuntu 17.10 artful / 18.04 bionic
Handle hotplug change on VLAN configuration using OVS
fix some minor bugs when using 'host-model' CPU.
v3.0.0 (2017-01-17) - Debian 9 stretch & 8 jessie-backports
v2.5.0 (2016-12-04) - Ubuntu 17.04 zesty
https://help.ubuntu.com/community/KVM/Installation
kvm-ok
apt-get install qemu-kvm libvirt-bin ubuntu-vm-builder bridge-utils
systemctl status libvirtd
cd /etc/libvirt/qemu && virsh define foo.xml
https://wiki.libvirt.org/page/FAQ#Where_are_VM_config_files_stored.3F_How_do_I_edit_a_VM.27s_XML_config.3F
https://fedoraproject.org/wiki/How_to_debug_Virtualization_problems
virt-host-validate
virsh capabilities
http://events.linuxfoundation.org/sites/events/files/slides/Debugging-libvirt-QEMU-in-OpenStack-2015-CloudOpen-Eu.pdf
/etc/libvirt/libvirtd.conf
log_filters="1:qemu 1:libvirt 3:security 3:event 3:util 3:file" log_outputs="1:file:/var/log/libvirt/libvirtd.log"
systemctl restart libvirtd
https://libvirt.org/logging.html
export LIBVIRT_DEBUG=1
export LIBVIRT_LOG_FILTERS="1:qemu 1:libvirt"
export LIBVIRT_LOG_OUTPUTS="1:journald 1:file:/tmp/virsh.log"
LIBVIRT_LOG_FILTERS:
x:name (log message only)
x:+name (log message + stack trace)
1: DEBUG
2: INFO
3: WARNING
4: ERROR
LIBVIRT_LOG_OUTPUTS
stderr output goes to stderr
syslog:name use syslog for the output and use the given name as the ident
file:file_path output to a file, with the given filepath
journald output goes to systemd journal
gdb: https://access.redhat.com/blogs/766093/posts/2690881
virsh list --all
virsh destroy ... # force off
export EDITOR=vim # for `virsh edit`
virsh dumpxml GuestID > guest.xml
virsh define guest.xml
virsh domxml-to-native qemu-argv demo.xml > demo.sh
virsh domxml-from-native qemu-argv demo.args > demo.xml
virsh snapshot-create-as --domain debian --name 'snapshot1'
virsh snapshot-list debian
qemu-img snapshot -l debian.qcow2 # when VM off
virsh pool-edit default # debian 9 default: /var/lib/libvirt/images/
https://fedorapeople.org/groups/virt/virtio-win/direct-downloads/stable-virtio/virtio-win.iso
https://github.com/torvalds/linux/blob/master/drivers/virtio/Kconfig
VIRTIO_BALLOON supports increasing and decreasing the amount of memory within a KVM guest.
VIRTIO_MMIO support for memory mapped virtio platform device driver.
http://docs.openvswitch.org/en/latest/howto/libvirt/
<interface type='bridge'>
<mac address='52:54:00:71:b1:b6'/>
<source bridge='ovs-br0'/>
<virtualport type='openvswitch'/>
<model type='virtio'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
</interface>
https://hicu.be/bridge-vs-macvlan
- Macvlan Bridge: VM-VM has bridge
- Macvlan private: VM-VM no communication
- Macvlan VEPA: VM-VM communicate via VEPA capable switch
https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Virtualization_Administration_Guide/sect-attch-nic-physdev.html
passthrough attaches a virtual function of a SRIOV capable NIC directly to a VM without losing the migration capability.https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Virtualization_Host_Configuration_and_Guest_Installation_Guide/App_Macvtap.html
when a guest virtual machine is configured to use a type='direct' network interface such as macvtap, ..., the guest cannot communicate with its own host.
My workaround: deassign macvtap host NIC's IP, and communicate with host's 2nd NIC.
try if no dhcp:
sysctl -w net.ipv4.conf.br0.bc_forwarding=1
sysctl -w net.bridge.bridge-nf-call-iptables=0
ip link set dev enp4s0 promisc on
https://libvirt.org/formatdomain.html#setting-vlan-tag-on-supported-network-types-only
<devices>
<interface type='bridge'>
<vlan>
<tag id='42'/>
</vlan>
<source bridge='ovsbr0'/>
vi /etc/init.d/libvirt-guests
ON_SHUTDOWN=shutdown
SHUTDOWN_TIMEOUT=10
systemctl enable libvirt-guests.service
booting with
kvm-intel.nested=1 argument on the kernel command line, or:
https://www.linux-kvm.org/page/Nested_Guests#How_to_runvirt-manager：enable
Copy host CPU configuration checkboxhttps://libvirt.org/kbase/virtiofs.html
https://www.kernel.org/doc/Documentation/vfio.txt
echo '0000:42:00.1' | sudo tee /sys/bus/pci/devices/0000:42:00.1/driver/unbind
echo 8086 1d02 | sudo tee /sys/bus/pci/drivers/vfio-pci/new_id
Support partion
<disk type='block' device='disk'>
<source dev='/dev/sdbX'/>
<target dev='vdb' bus='virtio'/>
</disk>
<source dev='/dev/disk/by-uuid/abcd1234'/>
cat /etc/default/grub | grep GRUB_CMDLINE_LINUX_DEFAULT
intel_iommu=on kvm-intel.nested=1 modprobe.blacklist=megaraid_sas,ahci,radeon,nouveau,nvidiafb,snd_hda_intel,...
update-grub
apt install -y ovmf
systemctl restart libvirtd
# select UEFI while creating VM
error while adding virt-manager NFS pool:
libvirtd[...]: cannot open volume '...': Transport endpoint is not connected
=> chmod +r
Last modified 4mo ago