Hello Tony Karera, Sorry for respone after a few days. I just got back from holiday. When there are notifications still in 'new', 'running' or 'error' status, it not allows to update or delete the host or segment [1]. In addition, if host reboot during upgrade the nodes kernel, it would trigger an host failure notification and recovery workflow. To avoid to set the hosts in maitenance mode, we advise that set the segment 'enabled' value 'False' before planned upgrade or maitenance [2]. [1]https://opendev.org/openstack/masakari/src/branch/master/masakari/ha/api.py L220 [2]https://opendev.org/openstack/masakari/src/branch/master/releasenotes/notes/... 发件人: Karera Tony [mailto:tonykarera@gmail.com] 发送时间: 2023年10月2日 15:09 收件人: openstack-discuss <openstack-discuss@lists.openstack.org> 主题: Masakari issue Hello Team, I have an openstack Wallaby Environment deployed using kolla-ansible. So, I shutdown all the VMs on the compute nodes becauseI wanted to upgrade the nodes kernel. After I rebooted them and all was fine apart from the fact that all the hosts in instance-ha segment are in maitenance mode. When I try to turn to false. I get the error below. Error: Failed to update host. <http://10.10.13.31/masakaridashboard/hosts/#message_details> Details ConflictException: 409: Client Error for url: http://x.x.x.x:15868/v1/segments/8d042245-5610-4b84-b611-b633f8f8367c/hosts/..., Host 066c5654-dd1a-4fa9-a664-dad10b89e202 can't be updated as it is in-use to process notifications. Regards Tony Karera