Hello Sam, Thanks for reporting this bug ! Yes I can confirm it is a bug, I managed to reproduce it on devstack and current release. To my mind, the volume should remain, but in a proper status (available and detached). By the way it seems that the boot volume is handled properly, but not supplemental attached volume. Here is the reproducer on my side: stack@openstack:~/nova$ openstack server list +--------------------------------------+------------+---------+-----------------------------------------------------------------------+--------------------------+--------+ | ID | Name | Status | Networks | Image | Flavor | +--------------------------------------+------------+---------+-----------------------------------------------------------------------+--------------------------+--------+ | 2360e339-5147-44b4-a4ac-87261b70abf2 | bug_detach | ACTIVE | private=10.0.0.4, fd4a:c3be:3d9c:0:f816:3eff:fe1c:5f7b | N/A (booted from volume) | ds512M | | efe970a5-b446-4d3e-869e-8221701e259c | demo | SHUTOFF | private=10.0.0.29, 172.24.4.211, fd4a:c3be:3d9c:0:f816:3eff:fef4:4b74 | N/A (booted from volume) | ds512M | +--------------------------------------+------------+---------+-----------------------------------------------------------------------+--------------------------+--------+ stack@openstack:~/nova$ openstack volume create --size 1 myvolume +---------------------+--------------------------------------+ | Field | Value | +---------------------+--------------------------------------+ | attachments | [] | | availability_zone | nova | | bootable | false | | consistencygroup_id | None | | created_at | 2023-11-07T14:14:39.510165 | | description | None | | encrypted | False | | id | cc6ed45a-90c5-4735-8048-1f4d20b6cf08 | | migration_status | None | | multiattach | False | | name | myvolume | | properties | | | replication_status | None | | size | 1 | | snapshot_id | None | | source_volid | None | | status | creating | | type | ceph | | updated_at | None | | user_id | 73800863dd9e4c799406254c518355ed | +---------------------+--------------------------------------+ stack@openstack:~/nova$ openstack volume list +--------------------------------------+----------+-----------+------+-------------------------------------+ | ID | Name | Status | Size | Attached to | +--------------------------------------+----------+-----------+------+-------------------------------------+ | cc6ed45a-90c5-4735-8048-1f4d20b6cf08 | myvolume | available | 1 | | | 1b98a735-9f75-44fa-9351-0eca65d3cffb | | in-use | 5 | Attached to bug_detach on /dev/vda | | b467c459-cd7d-4ea5-8ac2-6c1bfccc2ffc | | in-use | 5 | Attached to demo on /dev/vda | +--------------------------------------+----------+-----------+------+-------------------------------------+ stack@openstack:~/nova$ openstack --os-volume-api-version 3.27 volume attachment create myvolume bug_detach +-------------+--------------------------------------+ | Field | Value | +-------------+--------------------------------------+ | ID | 16c04c0c-0ad4-4223-a953-e7ae8bbad545 | | Volume ID | cc6ed45a-90c5-4735-8048-1f4d20b6cf08 | | Instance ID | 2360e339-5147-44b4-a4ac-87261b70abf2 | | Status | reserved | | Attach Mode | null | | Attached At | | | Detached At | | | Properties | | +-------------+--------------------------------------+ stack@openstack:~/nova$ openstack --os-volume-api-version 3.27 volume attachment list +--------------------------------------+--------------------------------------+--------------------------------------+----------+ | ID | Volume ID | Server ID | Status | +--------------------------------------+--------------------------------------+--------------------------------------+----------+ | 16c04c0c-0ad4-4223-a953-e7ae8bbad545 | cc6ed45a-90c5-4735-8048-1f4d20b6cf08 | 2360e339-5147-44b4-a4ac-87261b70abf2 | reserved | | 816d10d0-48b0-40a8-b60b-98a306264fb8 | 1b98a735-9f75-44fa-9351-0eca65d3cffb | 2360e339-5147-44b4-a4ac-87261b70abf2 | attached | | a3693d5c-f2a6-42da-8d4c-573909cbe839 | b467c459-cd7d-4ea5-8ac2-6c1bfccc2ffc | efe970a5-b446-4d3e-869e-8221701e259c | attached | +--------------------------------------+--------------------------------------+--------------------------------------+----------+ stack@openstack:~/nova$ openstack --os-volume-api-version 3.44 volume attachment complete 16c04c0c-0ad4-4223-a953-e7ae8bbad545 stack@openstack:~/nova$ openstack --os-volume-api-version 3.27 volume attachment list +--------------------------------------+--------------------------------------+--------------------------------------+----------+ | ID | Volume ID | Server ID | Status | +--------------------------------------+--------------------------------------+--------------------------------------+----------+ | 16c04c0c-0ad4-4223-a953-e7ae8bbad545 | cc6ed45a-90c5-4735-8048-1f4d20b6cf08 | 2360e339-5147-44b4-a4ac-87261b70abf2 | attached | | 816d10d0-48b0-40a8-b60b-98a306264fb8 | 1b98a735-9f75-44fa-9351-0eca65d3cffb | 2360e339-5147-44b4-a4ac-87261b70abf2 | attached | | a3693d5c-f2a6-42da-8d4c-573909cbe839 | b467c459-cd7d-4ea5-8ac2-6c1bfccc2ffc | efe970a5-b446-4d3e-869e-8221701e259c | attached | +--------------------------------------+--------------------------------------+--------------------------------------+----------+ stack@openstack:~/nova$ openstack server delete bug_detach stack@openstack:~/nova$ openstack --os-volume-api-version 3.27 volume attachment list +--------------------------------------+--------------------------------------+--------------------------------------+----------+ | ID | Volume ID | Server ID | Status | +--------------------------------------+--------------------------------------+--------------------------------------+----------+ | 16c04c0c-0ad4-4223-a953-e7ae8bbad545 | cc6ed45a-90c5-4735-8048-1f4d20b6cf08 | 2360e339-5147-44b4-a4ac-87261b70abf2 | attached | | a3693d5c-f2a6-42da-8d4c-573909cbe839 | b467c459-cd7d-4ea5-8ac2-6c1bfccc2ffc | efe970a5-b446-4d3e-869e-8221701e259c | attached | +--------------------------------------+--------------------------------------+--------------------------------------+----------+ stack@openstack:~/nova$ openstack volume list +--------------------------------------+----------+-----------+------+-----------------------------------------------------------+ | ID | Name | Status | Size | Attached to | +--------------------------------------+----------+-----------+------+-----------------------------------------------------------+ | cc6ed45a-90c5-4735-8048-1f4d20b6cf08 | myvolume | in-use | 1 | Attached to 2360e339-5147-44b4-a4ac-87261b70abf2 on None | | 1b98a735-9f75-44fa-9351-0eca65d3cffb | | available | 5 | | | b467c459-cd7d-4ea5-8ac2-6c1bfccc2ffc | | in-use | 5 | Attached to demo on /dev/vda | +--------------------------------------+----------+-----------+------+-----------------------------------------------------------+ stack@openstack:~/nova$ openstack volume set --state error cc6ed45a-90c5-4735-8048-1f4d20b6cf08 stack@openstack:~/nova$ openstack volume list +--------------------------------------+----------+-----------+------+-----------------------------------------------------------+ | ID | Name | Status | Size | Attached to | +--------------------------------------+----------+-----------+------+-----------------------------------------------------------+ | cc6ed45a-90c5-4735-8048-1f4d20b6cf08 | myvolume | error | 1 | Attached to 2360e339-5147-44b4-a4ac-87261b70abf2 on None | | 1b98a735-9f75-44fa-9351-0eca65d3cffb | | available | 5 | | | b467c459-cd7d-4ea5-8ac2-6c1bfccc2ffc | | in-use | 5 | Attached to demo on /dev/vda | +--------------------------------------+----------+-----------+------+-----------------------------------------------------------+ stack@openstack:~/nova$ openstack volume delete cc6ed45a-90c5-4735-8048-1f4d20b6cf08 Failed to delete volume with name or ID 'cc6ed45a-90c5-4735-8048-1f4d20b6cf08': Invalid volume: Volume status must be available or error or error_restoring or error_extending or error_managing and must not be migrating, attached, belong to a group, have snapshots, awaiting a transfer, or be disassociated from snapshots after volume transfer. (HTTP 400) (Request-ID: req-e8232e34-22c0-4ebe-b6fe-f2d06cd37258) 1 of 1 volumes failed to delete. stack@openstack:~/nova$ openstack volume set --detached cc6ed45a-90c5-4735-8048-1f4d20b6cf08 stack@openstack:~/nova$ openstack volume list +--------------------------------------+----------+-----------+------+-------------------------------+ | ID | Name | Status | Size | Attached to | +--------------------------------------+----------+-----------+------+-------------------------------+ | cc6ed45a-90c5-4735-8048-1f4d20b6cf08 | myvolume | available | 1 | | | 1b98a735-9f75-44fa-9351-0eca65d3cffb | | available | 5 | | | b467c459-cd7d-4ea5-8ac2-6c1bfccc2ffc | | in-use | 5 | Attached to demo on /dev/vda | +--------------------------------------+----------+-----------+------+-------------------------------+ stack@openstack:~/nova$ openstack volume delete cc6ed45a-90c5-4735-8048-1f4d20b6cf08