QEMU-KVM Quick Reference

Convert raw/.img to .qcow2

[root@vhost1 ~]# qemu-img convert -f raw -O qcow2 <hdd-file>.img <hdd-file>.qcow2

Disk info
[root@vhost1 images]# qemu-img info <hdd-file>

Snapshot

List snapshot(s):
[root@vhost1 ~]# virsh snapshot-list qa-server

Create snapshot:
[root@vhost1 ~]# virsh snapshot-create-as <vm-name> <snapshot-name> "<snapshot-description>" --disk-only --atomic

Revert snapshot:
[root@vhost1 ~]# virsh snapshot-revert <vm-name> <snapshot-name>

Virtual Networking

[root@vhost1 ~]# brctl show
[root@vhost1 ~]# brctl addbr <bridge-name>
[root@vhost1 ~]# brctl delbr <bridge-name>
[root@vhost1 ~]# brctl addif <bridge-name> <if-name>
[root@vhost1 ~]# brctl delif <bridge-name> <if-name>
[root@vhost1 ~]# brctl showmacs <bridge-name>
[root@vhost1 ~]# brctl stp <bridge-name> on

http://www.linuxfoundation.org/collaborate/workgroups/networking/bridge 
http://www.linuxjournal.com/article/10821