[libvirt-users] libvirt beginner needs to create and start VMs entirely on command line

I'm a beginner to libvirt and creating VMs, for that matter. I have a set of specifications for VMs I need to create and log into, but I have to create them on an Ubuntu box that I only have ssh access to. I won't have desktop GUI access, although I do have dynamic port forwarding, so I can access a browser GUI from my desktop. Reading through the libvirt info, I see numerous mentions about using VNC to do additional work, but I won't be able to use VNC (not allowed within our firewall). I could use some advice on how to move forward with this. I've started at https://help.ubuntu.com/lts/serverguide/libvirt.html for initial information. I managed to create a disk image for my first VM, and I believe I created the first VM using an ISO (based on CentOS, I believe), but I'll probably have to rebuild that, because I think I have to configure networks on the VM, which I didn't do on initial creation. I was confused by the initial results from "virt-install", because it seemed to hang after a second or two (I posted this SO question about this: http://stackoverflow.com/questions/31302871/trouble-using-virt-install-on... ). The reply from this makes it seem like it was trying to present a GUI for next steps, but I of course never saw that. The VM appears to exist, but in a "shut off" state.