Comment 1 for bug 1807723

I'm not sure if multiple hosts is really the main culprit because the test passed on this tempest-slow job:

http://logs.openstack.org/78/606978/4/check/tempest-slow/63b3e0e/

And in that case, the two servers involved in the swap from the same multiattach volume are on different hosts. So maybe there is some timing issue involved when this fails.

In that passing case, these are the two servers:

Body: {"servers": [{"id": "988b38e6-1556-45b8-94ba-76d5045ef5e9", "links": [{"href": "https://10.210.68.80/compute/v2.1/servers/988b38e6-1556-45b8-94ba-76d5045ef5e9", "rel": "self"}, {"href": "https://10.210.68.80/compute/servers/988b38e6-1556-45b8-94ba-76d5045ef5e9", "rel": "bookmark"}], "name": "tempest-TestMultiAttachVolumeSwap-server-1095754502-2"}, {"id": "2f4078c8-4911-4154-b24b-ea2ca37fcdd3", "links": [{"href": "https://10.210.68.80/compute/v2.1/servers/2f4078c8-4911-4154-b24b-ea2ca37fcdd3", "rel": "self"}, {"href": "https://10.210.68.80/compute/servers/2f4078c8-4911-4154-b24b-ea2ca37fcdd3", "rel": "bookmark"}], "name": "tempest-TestMultiAttachVolumeSwap-server-1095754502-1"}]} _log_request_full tempest/lib/common/rest_client.py:437

988b38e6-1556-45b8-94ba-76d5045ef5e9 (server2) builds on the primary node and 2f4078c8-4911-4154-b24b-ea2ca37fcdd3 (server1) builds on the subnode.

Maybe it depends on where volume1 builds? In that test, volume1 is 2fe7ad08-b928-4139-9f9d-a4ee54ac630d which builds on the primary node, and if server1 is on the subnode, then that is one difference from the fail scenario where volume1 and server1 are on the same host.