On Tue, 2016-04-26 at 09:36 +0800, zhukaijie wrote: > Once I type my qemu command line in bash shell and execute it. > Then I use ps -aux to list the qemu process, results > indicates the user of the qemu vm is "root" (Of course I logged > with root). However, if I use libvirt to start a qemu > vm, the user of qemu become "qemu". Could you tell me something > about the user "qemu"? Also, how does this difference > happen? Thank you. libvirt will launch qemu processes as a different user for security reasons: while the libvirtd process needs to be running as root in order to perform system setup tasks, the guest processes themselves don't need to, and the overall system security / stability benefits from them running as a different user. You can override the user (I believe "qemu" to be the default) by changing the "user" and "group" settings in your /etc/libvirt/qemu.conf. On a side note, this mailing list is about the development of libvirt itself; please send inquiries about libvirt usage to the libvirt-users@xxxxxxxxxx mailing list instead. -- Andrea Bolognani Software Engineer - Virtualization Team -- libvir-list mailing list libvir-list@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/libvir-list