I should add, this is a further problem:
$ ssh -i /home/ubuntu/.config/maas-test/vm_ssh_id_rsa ubuntu@192.168.122.199
Warning: Identity file /home/ubuntu/.config/maas-test/vm_ssh_id_rsa not accessible: Permission denied.
Permission denied (publickey).
I should add, this is a further problem: .config/ maas-test/ vm_ssh_ id_rsa ubuntu@ 192.168. 122.199 .config/ maas-test/ vm_ssh_ id_rsa not accessible: Permission denied.
$ ssh -i /home/ubuntu/
Warning: Identity file /home/ubuntu/
Permission denied (publickey).