Add the Nova CpuFlagsFilter custom filter

Add the Nova CpuFlagsFilter custom filter


This feature is available starting from the MCP 2019.2.10 maintenance update. Before using the feature, follow the steps described in Apply maintenance updates.

CpuFlagsFilter is a custom Nova scheduler filter for live migrations. The filter ensures that the CPU features of a live migration source host match the target host. Use the CpuFlagsFilter filter only if your deployment meets the following criteria:

  • The CPU mode is set to host-passthrough or host-model. For details, see MCP Deployment Guide: Configure a CPU model.

  • The OpenStack compute nodes have heterogeneous CPUs.

  • The OpenStack compute nodes are not organized in aggregates with the same CPU in each aggregate.

To add the Nova CpuFlagsFilter custom filter:

  1. Open your project Git repository with the Reclass model on the cluster level.

  2. Open the classes/cluster/<cluster_name>/openstack/control.yml file for editing.

  3. Verify that the cpu_mode parameter is set to host-passthrough or host-model.

  4. Add CpuFlagsFilter to the scheduler_default_filters parameter for nova:contoroller:

        scheduler_default_filters: “DifferentHostFilter,SameHostFilter,RetryFilter,AvailabilityZoneFilter,RamFilter,CoreFilter,DiskFilter,ComputeFilter,ComputeCapabilitiesFilter,ImagePropertiesFilter,ServerGroupAntiAffinityFilter,ServerGroupAffinityFilter,PciPassthroughFilter,NUMATopologyFilter,AggregateInstanceExtraSpecsFilter,CpuFlagsFilter”
  5. Log in to the Salt Master node.

  6. Apply the changes:

    salt -C 'I@nova:controller' state.sls nova.controller