Comment 11 for bug 2037752

I just learned that -1 are our default values in the database. These get updated once we establish a connection to the virsh host and update to the real numbers.
That said, it's likely a problem with the connection to virsh or the SSH key. Can you try composing the host via the CLI?
You can find instructions here (make sure to switch to CLI): https://maas.io/docs/how-to-manage-vm-hosts#heading--configuration .