How do I prevent virt-manager from asking for the root password?

/etc/polkit-1/rules.d/10.virt.rules:

polkit.addRule(function(action, subject) {
    if (action.id == "org.libvirt.unix.manage"
            && subject.local
            && subject.active
            && subject.isInGroup("libvirt")) {
        return polkit.Result.YES;
    }
});

You'll have to perform common steps including restarting policykit and starting a new session with the respective user after adding him to the libvirt group.

It looks like the resource is about Fedora 18 but it uses the javascript syntax already so it's most probably valid for Fedora 19 as well.

Links:

• http://goldmann.pl/blog/2012/12/03/configuring-polkit-in-fedora-18-to-access-virt-manager/
• http://niranjanmr.wordpress.com/2013/03/20/auth-libvirt-using-polkit-in-fedora-18/
• http://davidz25.blogspot.in/2012/06/authorization-rules-in-polkit.html

I found that simply adding my user to libvirt and kvm groups stopped the prompts.

sudo usermod -a -G libvirt yourusername
sudo usermod -a -G kvm yourusername

The password prompt was made for system security so if you do this might make it vulnerable.

1. Create the Group group on your machine. or you can run this "sudo groupadd -r Group"

2. You can any user you want to this system group by runing "sudo usermod -a -G Group User"

3. Now you need to create our PolicyKit policy that will allow the users of Group to run virt-manager

you will create a file at this path:"/etc/polkit-1/localauthority/50-local.d/50-org.Group-libvirt-local-access.pkla"
and you will put lines below in it

[Allow group Group libvirt management permissions]
Identity=unix-group:Group
Action=org.libvirt.unix.manage
ResultAny=yes
ResultInactive=yes
ResultActive=yes

Thats all you needed to do now you can run it. And i hope this helps you.