Comment 3 for bug 1820007

This is what Lee Yarwood said about the problem when investigating the failed CI job run:

(11:52:13 AM) lyarwood: mriedem_afk: actually os-brick is doing some random lookups when encrypted volumes are used
(12:03:53 PM) lyarwood: mriedem_afk: so it looks like /dev/disk/by-id/ is just slow to populate on these CI nodes and we aren't retrying the lookup https://github.com/openstack/os-brick/blob/1c02d525bb77487d5de89c4bd58116b916d44207/os_brick/initiator/connectors/iscsi.py#L521-L540
(12:04:33 PM) lyarwood: mriedem_afk: the fact we are using /dev/disk/by-id/ is due to the volume being encrypted https://github.com/openstack/os-brick/blob/1c02d525bb77487d5de89c4bd58116b916d44207/os_brick/initiator/connectors/iscsi.py#L545-L553
(12:05:40 PM) lyarwood: mriedem_afk: and is due to the horrid design of the original encryptors that symlink things in a horrific way such that we can't use the actual block device path on the host otherwise we'd nuke it https://bugs.launchpad.net/os-brick/+bug/1703954
(12:05:41 PM) openstack: Launchpad bug 1703954 in OpenStack Compute (nova) "Attach/Detach encrypted volume problems with real paths" [Undecided,Incomplete]
(12:07:26 PM) lyarwood: mriedem_afk: I'll post something in the morning to retry _get_device_link but in the longer term I think I need to sort out the symlinking in the encryptors such that it's safe to provide them with a real block device path and they don't do anything stupid.