Fab : Launching a Guest with global option fails if uid/gid of nova is different on compute nodes

[Vinod Nair]

Live migration fails as UID and GID are different on compute nodes..
In my testbed.py i had set cfgm to run on two nodes and database on two nodes,

cassandra:x:106:110:Cassandra database,,,:/var/lib/cassandra:/bin/false
contrail:x:107:111::/var/lib/contrail:/bin/false
neutron:x:108:112::/var/lib/neutron:/bin/false
haproxy:x:109:113::/home/haproxy:/bin/false
rabbitmq:x:110:114:RabbitMQ messaging server,,,:/var/lib/rabbitmq:/bin/false
statd:x:111:65534::/var/lib/nfs:/bin/false
nova:x:112:116::/var/lib/nova:/bin/false
libvirt-qemu:x:113:115:Libvirt Qemu,,,:/var/lib/libvirt:/bin/false

  File "/usr/lib/python2.7/dist-packages/nova/compute/manager.py", line 1413, in _spawn\n LOG.exception(_(\'Instance failed to spawn\'), instance=instance)\n', u' File "/usr/lib/python2.7/dist-packages/nova/compute/manager.py", line 1410, in _spawn\n block_device_info)\n', u' File "/usr/lib/python2.7/dist-packages/nova/virt/libvirt/driver.py", line 2064, in spawn\n admin_pass=admin_password)\n', u' File "/usr/lib/python2.7/dist-packages/nova/virt/libvirt/driver.py", line 2303, in _create_image\n fileutils.ensure_tree(basepath(suffix=\'\'))\n', u' File "/usr/lib/python2.7/dist-packages/nova/openstack/common/fileutils.py", line 38, in ensure_tree\n os.makedirs(path)\n', u' File "/usr/lib/python2.7/os.py", line 157, in makedirs\n mkdir(name, mode)\n', u"OSError: [Errno 13] Permission denied: '/var/lib/nova/instances/global/6a9b75f0-239b-4372-8262-5947b5635b49/'\n"]

[Michael Nishimoto (mnishimoto)]

Add 'fab setup_uids_gids' and must be called before 'fab install_contrail' if storage will be installed and setup later on.

[Michael Nishimoto (mnishimoto)]

The users which need to be added:

nova
libvirt-qemu

and maybe : libvirt-dnsmasq

The groups which need to be added:

kvm
nova

and maybe : libvirtd