Troubleshooting reservation updates

This page shows you how to resolve issues with modifying reservations. To learn more about reservations, see Reservations of Compute Engine zonal resources.

Attempt to delete a reservation's compact placement policy

The following error occurs when you try to delete a reservation's compact placement policy before deleting the reservation.

Error message:

The resource_policy resource 'projects/PROJECT_ID/regions/REGION/resourcePolicies/COMPACT_PLACEMENT_POLICY_NAME' is already being used by 'projects/PROJECT_ID/zones/ZONE/reservations/RESERVATION_NAME'

Resolution: To delete a compact placement policy specified in a reservation, select one of the following methods:

If you created the reservation by specifying an instance template, follow these steps:
1. View the details of the reservation and make note of the reservation's instance template.
2. Delete the reservation.
3. Delete the instance template.
  
  Note: You can't update instance templates. If you delete a compact placement policy specified in an instance template, attempting to use the template to create reservations or virtual machine (VM) instances causes errors.
4. Delete the compact placement policy.
If you created the reservation by specifying properties directly, follow these steps:
1. Delete the reservation.
2. Delete the compact placement policy.

Attempt to downsize a specific reservation to less VMs than the targeted number

The following error occurs when you try to decrease the number of reserved VMs in a specific reservation to a number that is lower than the number of VMs that consume the reservation.

Error message:

The resize instance count cannot be lower than the in use count for a specific reservation.

Resolution: To ensure that the number of VMs in the specific reservation is equal to or lower than the number of VMs that consume the reservation, do one of the following with the VMs in excess:

Delete VMs
Stop or suspend the VMs

Caution: If you stop or suspend instances in excess instead of deleting them, then those instances no longer count against the reservation, and you can proceed to modify the reservation. However, after you modify the reservation, you can't restart or resume the instances unless you increase the number of instances in the reservation or delete other instances that are consuming it.

Reservation capacity limit exceeded

The following error occurs when you try to increase the number of reserved VMs in an on-demand reservation, but the zone lacks available reservation capacity for your requested machine family.

Error messages:

RESERVATION_CAPACITY_LIMIT_EXCEEDED

Failed to reserve additional capacity for 'MACHINE_FAMILY' because reservation capacity limit exceeded in 'ZONE'. Select a different machine family or zone.

Resolution: If you try to increase the number of reserved VMs in an automatically consumed reservation and consume existing, running VMs, then Compute Engine rejects the request when the zone lacks reservation capacity. This rejection prevents Compute Engine from charging you twice for the running VMs and an unused reservation. To resolve this error, try one or more of the following options:

Use a different zone. Create a reservation in a zone that has available capacity for your requested machine family.
Use a different machine family. Create a reservation that specifies a machine type from a different machine family.
Reduce the VM count. Request fewer VMs in the reservation.
Retry later. Submit the modification request again at a later time.