Category Archives: kvm

kvm virtualization

kvm performance tuning.

By | April 7, 2018

Set swappiness to 10, swap space will be used at or 90% usage of system ram, generally on linux systems this value is 60. Checking the current swappiness value cat /proc/sys/vm/swappiness 60 To change the value at system run time use #sysctl -w vm.swappiness=10 vm.swappiness = 10 To keep the changes permanent we can add… Read More »

Category: kvm

kvm/qemu pxe boot setup on fedora.

By | April 6, 2018

kvm support disk less booting of operating systems over network, kvm default network can be configured to act a pxe server. packages required to setup pxe boot, tfp is a udp based file sharing service used to push the required files for pxe boor, /var/lib/tftpboot will be directory for tftp server. we need to copy… Read More »

Category: kvm

Scheduling disk i/o on fedora 26.

By | April 2, 2018

Scheduling disk i/o on fedora 26. By default on linux machines cfq i/o scheduler is used, Completely Fair Queuing (CFQ) is an I/O scheduler for the Linux kernel. cfq scheduler is generally idel and suitbale for genreal system workloads. If the server is used for virtualization like kvm,vmware it needs to have optimized throughput. for… Read More »

Category: kvm

Virt-manager error on fedora 26

By | April 2, 2018

Virt-manager error on fedora 26 virt-manager is a graphical tool to manage kvm vms on a host, due to some dependency or reinstall of libvirt can cause virt-manger show below error $virt-manager Traceback (most recent call last): File “/usr/share/virt-manager/virt-manager”, line 35, in <module> from virtinst import util as util File “/usr/share/virt-manager/virtinst/__init__.py”, line 39, in <module>… Read More »

Category: kvm

libvirt volume management.

By | April 1, 2018

On libvirt default storage pool is created called default, default pool will defined to use use location /var/lib/libvirt/images for file based volumes. when ever i create a kvm vm it will create a image in .qcow2 default disk storage for the newly created vm, in other words it is called as volume. Each vm created… Read More »

Category: kvm

kvm custom storage pool on lvm partition.

By | March 30, 2018

libvirtd by default has a storage pool called default, we can create additional storage pools from a simple xml file $ cat store.xml <pool type=”logical”> <name>store</name> <source> <device path=”/dev/sda1″/> </source> <target> <path>/dev/store</path> </target> </pool> Once the xml file is created , lets define it $ virsh pool-define store.xml Pool store defined from store.xml $ virsh… Read More »

Category: kvm

Configuring dhcp static ip assignment to kvm host vms

By | March 17, 2018

Libvird by dedfault uses dnsmasq to provide ip address for kvm host vms automatically when libvirtd daemon is started. virtual network switch can be provided ip address from dhcp,it uses dnsmasq server. use the below bash one liner to print all the kvm mac address and respective host name #virsh list –all | awk ‘{print… Read More »

Category: kvm

Libvirt / kvm basics

By | March 7, 2018

installing kvm, Lets check whether the host supports virtualization # grep -E ‘svm|vmx’ /proc/cpuinfo flags : fpu vme de pse tsc msr pae mce cx8 apic sep mtrr pge mca cmov pat pse36 clflush dts acpi mmx fxsr sse sse2 ss ht tm pbe syscall nx lm constant_tsc arch_perfmon pebs bts rep_good nopl cpuid aperfmperf… Read More »

Category: kvm

setting up kvm on fedora 27

By | March 6, 2018

KVM stands for Kernel based Virtual-machine which provides capabilities to run multiple multiple hosts on a system. dnf @virtualization bridge-utils qemu-kvm virt-manager virt-install qemu-img libvirt libvirt-python libvirt-client -y after installing libvirt tools when accessing virsh as a normal user you will prompted for authentication. $libvirt ==== AUTHENTICATING FOR org.libvirt.unix.manage === System policy prevents management of… Read More »

Category: kvm

Setting up a kvm bridge on fedora 26.

By | February 24, 2018

A network  connects more network segments. A  software bridge behaves like a virtual network switch to which any physical or virtual devices can be connected. 1.Adding a bridge. #brctl addbr br0 Check the bridge status. #brctl show | grep br0 br0 8000.000000000000 no 2.Create a configuration file for the bridge and add  enp9s0 to it.… Read More »

Category: kvm