Looking at nova-compute.log I see errors trying to find LUN 0 during the sysfs stage.

Several machines won't boot because their root disk entries in LVM are seen as PV and booting them doesn't see them in the DM subsystem.

Other machines boot but there attached disks throw LVM errors about duplicate PV and preferring the cinder-volumes VG version.

LVM is showing LVs that have both "bare" entries as well as entries in cinder-volumes and it's complaining about duplicate PVs, not using lvmetad and preferring some entries because they are in the dm subsystem.

I've verified that, so far, I haven't lost any data. The "bare" LV not being used as part of the DM subsystem because it's server won't boot can be mounted on the openstack host and all data on it is accessible.

This host has rebooted cleanly multiple times in the past. This is the first time it's shown any problems.

Am I missing an LVM filter? (unlikely since it wasn't neede before)

How can I reset the LVM configuration and convince it that it's not seeing duplicate PV?

How do I ensure that openstack sees the right UUID and volume ID?

Excerpts from error log and output of lvs :

--- nova-compute.log --- during VM start

2020-09-24 11:15:27.091 13953 INFO os_brick.initiator.connectors.iscsi [req-8d15fb6a-6324-471e-9497-587885eef8f6 396aeda6552f44fdac5f878b90325ee1 54af92f2bb494355b96024076184d1c8
 - default default] Trying to connect to iSCSI portal 172.10.0.40:3260
2020-09-24 11:15:29.721 13953 WARNING nova.compute.manager [req-fd32e16f-c879-402f-a32c-6be45a943c34 48af9a366301467d9fec912fd1c072c6 f9fc7b412a8446d083da1356aa370eb4 - default d
efault] [instance: de7d740c-786a-4aa2-aa09-d447ae7e14b6] Received unexpected event network-vif-unplugged-79aff403-d2e4-4266-bd88-d7bd19d501a9 for instance with vm_state stopped a
nd task_state powering-on.
2020-09-24 11:16:21.361 13953 WARNING os_brick.initiator.connectors.iscsi [req-8d15fb6a-6324-471e-9497-587885eef8f6 396aeda6552f44fdac5f878b90325ee1 54af92f2bb494355b96024076184d
1c8 - default default] LUN 0 on iSCSI portal 172.10.0.40:3260 not found on sysfs after logging in.
2020-09-24 11:16:23.482 13953 INFO os_brick.initiator.connectors.iscsi [req-8d15fb6a-6324-471e-9497-587885eef8f6 396aeda6552f44fdac5f878b90325ee1 54af92f2bb494355b96024076184d1c8
 - default default] Trying to connect to iSCSI portal 172.10.0.40:3260
2020-09-24 11:17:17.741 13953 WARNING os_brick.initiator.connectors.iscsi [req-8d15fb6a-6324-471e-9497-587885eef8f6 396aeda6552f44fdac5f878b90325ee1 54af92f2bb494355b96024076184d
1c8 - default default] LUN 0 on iSCSI portal 172.10.0.40:3260 not found on sysfs after logging in.: VolumeDeviceNotFound: Volume device not found at .
2020-09-24 11:17:21.864 13953 INFO os_brick.initiator.connectors.iscsi [req-8d15fb6a-6324-471e-9497-587885eef8f6 396aeda6552f44fdac5f878b90325ee1 54af92f2bb494355b96024076184d1c8
 - default default] Trying to connect to iSCSI portal 172.10.0.40:3260
2020-09-24 11:18:16.113 13953 WARNING os_brick.initiator.connectors.iscsi [req-8d15fb6a-6324-471e-9497-587885eef8f6 396aeda6552f44fdac5f878b90325ee1 54af92f2bb494355b96024076184d
1c8 - default default] LUN 0 on iSCSI portal 172.10.0.40:3260 not found on sysfs after logging in.: VolumeDeviceNotFound: Volume device not found at .
2020-09-24 11:18:17.252 13953 INFO nova.compute.manager [req-8d15fb6a-6324-471e-9497-587885eef8f6 396aeda6552f44fdac5f878b90325ee1 54af92f2bb494355b96024076184d1c8 - default defa
ult] [instance: de7d740c-786a-4aa2-aa09-d447ae7e14b6] Successfully reverted task state from powering-on on failure for instance.
2020-09-24 11:18:17.279 13953 ERROR oslo_messaging.rpc.server [req-8d15fb6a-6324-471e-9497-587885eef8f6 396aeda6552f44fdac5f878b90325ee1 54af92f2bb494355b96024076184d1c8 - defaul
t default] Exception during message handling: VolumeDeviceNotFound: Volume device not found at .
2020-09-24 11:18:17.279 13953 ERROR oslo_messaging.rpc.server Traceback (most recent call last):
2020-09-24 11:18:17.279 13953 ERROR oslo_messaging.rpc.server   File "/usr/lib/python2.7/site-packages/oslo_messaging/rpc/server.py", line 163, in _process_incoming
2020-09-24 11:18:17.279 13953 ERROR oslo_messaging.rpc.server     res = self.dispatcher.dispatch(message)
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