231003_Linux上跑KVM虚拟机

既然我本机是Linux，那运行虚拟机何不用KVM呢。如果是win/mac，那还用不了KVM(1类虚拟机)，只能用virtualbox,vmware(2类虚拟机)。

流れ简单说就是：安装环境；启动libvirt daemon；开启虚拟网络；virt-manager作为前端界面可以在里面操作了

检查处理器是否支持硬件虚拟化

LC_ALL=C lscpu | grep Virtualization

现在的处理器肯定都是支持的，If it looks like your processor does not support virtualization, it is almost certainly turned off in the BIOS.

KVM(Kernel-based Virtual Machine)集中在Linux内核里了，不需要安装

安装qemu

sudo pacman -S qemu

选qemu-full

安装libvert (检查iptables-nft 有没有，没的话装上)

sudo pacman -S libvirt

安装virt-manager

sudo pacman -S virt-manager

==开启libvirt daemon (不然之后的virshなど都用不了)==

systemctl start libvirtd

加入libvirt user group (archwiki写了，~~但我没这样做~~ 担心和虚拟机的稳定性有关，还是加入了)

sudo usermod -a -G libvirt $(whoami)

应该打开virt-manager不需要输入口令了

安装其他可能有用的包

sudo pacman -S ovmf vde2 dnsmasq bridge-utils openbsd-netcat

(archwikiによると、ebtables已经被iptables的功能包含了，所以不需要了)

创建的虚拟机的虚拟硬盘存放在/var/lib/libvirt/images下面.qcow2文件

用virt-manager创建虚拟机，startしようとするところ、虚拟网络报错：

Requested operation is not valid: network 'default' is not active

解决：https://askubuntu.com/questions/1036297/cant-start-kvm-guest-network-default-is-not-active

First, confirm that the default network is indeed inactive:

sudo virsh net-list --all

If so, ==start the default network==:

sudo virsh net-start default

Run the first command line again to see if it worked.

https://github.com/kubernetes/minikube/issues/828 这里还看到了

First time users need currently do:

virsh net-autostart default
virsh net-start default

虽然我net-autostart就没実行了

但我sudo virsh net-start default又报错：

error: Failed to start network default
error: internal error: firewalld is set to use the nftables backend, but the required firewalld 'libvirt' zone is missing. Either set the firewalld backend to 'iptables', or ensure that firewalld has a 'libvirt' zone by upgrading firewalld to a version supporting rule priorities (0.7.0+) and/or rebuilding libvirt with --with-firewalld-zone

问了chatgpt，我就试着开启iptables