Symptoms
An ESX host fails to enter maintenance mode in a VMware High Availability (HA) or DRS cluster. Virtual machines do not vMotion when attempting to enter maintenance mode. You receive an error in vCenter similar to:Waiting for all VMs to be powered off or migrated. In a DRS cluster check the Faults page on the DRS tab for troubleshooting The progress indicator remains at 2% indefinitely. Trying to remediate a host and getting a time out error when trying to enter the maintenance mode.
Purpose
This article provides an explanation for the behavior and includes a workaround. Note: The workaround provided may take a significant amount of time to complete.
Resolution
This is a normal behavior for a VMware HA/DRS cluster that is using strict admission control. Disabling strict admission control (allowing virtual machines to power on even if they violate constraints) should allow a host to enter maintenance mode in this situation. A bug was discovered that would not allow a host to enter maintenance mode even if strict admission control was disabled. However, this was resolved in VirtualCenter 2.5 Update 3 and disabling strict admission control should now allow hosts to enter maintenance mode correctly. To work around the issue, temporarily disable VMware HA in the cluster settings. After disabling the HA in the cluster settings, you can put the ESX Server host into Maintenance Mode, do the work required, and then re-enable HA on your cluster. For detailed steps, see VMware High Availability: Concepts, Implementation, and Best Practices. Note: DRS needs to be enabled on your cluster in Fully Automated mode if you want VirtualCenter to migrate your running virtual machines automatically to other hosts when placing your host in Maintenance Mode.
Related Information
For more information, see: ESXi/ESX host fails to go into maintenance mode (1036167) ESX/ESXi host unable to enter maintenance mode in a two node cluster (1017330)ESX/ESXi host unable to enter maintenance mode in a two node clusterESXi/ESX host fails to go into maintenance modeESX/ESXi ホストが VMware High Availability クラスタでメンテナンス モードに切り替わらず、2% で停止するVMware High Availability 群集中的 ESX/ESXi 主机无法进入维护模式并在进展到 2% 时停止
