"Unable to apply DRS resource settings on host" error in vCenter Server

Products

• VMware vSphere ESXi 8.0
• VMware vSphere ESXi 7.0
• VMware vSphere ESXi 6.0
• VMware vCenter Server 8.0
• VMware vCenter Server 7.0
• VMware vCenter Server 6.0

Issue/Introduction

An ESX host in vCenter Server reports the error:

 

Unable to apply DRS resource settings on host. The operation is not allowed in the current state. This can significantly reduce the effectiveness of DRS.
WARNING: UserDuct: 184: Cannot allocate a new data segment, out of memory

Environment

This issue impacts vCenter & ESXi 6.x, 7.x, and 8.x.

Resolution

This warning does not have a direct impact on production virtual machines but can result in resource contention within the cluster if DRS is not functioning correctly.

To resolve this issue, restart the management agents (hostd and vpxa) on the host.

 

/etc/init.d/hostd restart
/etc/init.d/vpxa restart

Workaround

Warning: The following steps should not be executed on a VSAN, NSX, VCD, or Horizon View-enabled cluster.

If the problem persists after restarting the management agents, remove the host from the cluster and then re-add it:

1. Place the host into maintenance mode.

Note: If DRS does not migrate the virtual machines to other hosts, migrate them manually.

2. Ensure that no virtual machines are running on the host.
3. Remove the ESXi/ESX host by dragging it out of the cluster.
4. Re-add the ESXi/ESX host by dragging it into the cluster.
5. Exit from maintenance mode.

Additional Information

This issue can also occur if a powered-on VM was moved to a resource pool. See Error: "Unable to apply DRS resource settings on host" after a Powered on VM moves to a Resource Pool for more details.

 

VMware Skyline Health Diagnostics for vSphere - FAQ
"Unable to apply DRS resource settings on host" warning in summary tab of the ESXi host
Restarting the Management agents in ESXi