VMware live migration¶
https://blueprints.launchpad.net/nova/+spec/vmware-live-migration
This is a proposal for adding support for live migration in the VMware driver. When the VMware driver is used, each nova-compute is managing a single vCenter cluster. For the purposes of this proposal we assume that all nova-computes are managing clusters under the same vCenter server. If migration across different vCenter servers is attempted, an error message will be generated and no migration will occur.
Problem description¶
Live migration is not supported when the VMware driver is used.
Use Cases¶
As an Operator I want to live migrate instances from one compute cluster (nova-compute host) to another compute cluster (nova-compute host) in the same vCenter server.
Proposed change¶
Relocating VMs to another cluster/datastore is a simple matter of calling the RelocateVM_Task() vSphere API. The source compute host needs to know the cluster name and the datastore regex of the target compute host. If the instance is located on a datastore shared between the two clusters, it will remain there. Otherwise we will choose a datastore that matches the datastore_regex of the target host and migrate the instance there. There will be a pre live-migration check that will verify that both source and destination compute nodes correspond to clusters in the same vCenter server.
A new object will be introduced (VMwareLiveMigrateData) which will carry the host IP, the cluster name and the datastore regex of the target compute host. All of them are obtained from the nova config (CONF.vmware.host_ip, CONF.vmware.cluster_name and CONF.vmware.datastore_regex).
Alternatives¶
None
Data model impact¶
None
REST API impact¶
None
Security impact¶
None
Notifications impact¶
None
Other end user impact¶
None
Performance Impact¶
None
Other deployer impact¶
None
Developer impact¶
None
Upgrade impact¶
None
Implementation¶
https://review.openstack.org/#/c/270116/
Assignee(s)¶
- Primary assignee:
rgerganov
Work Items¶
Add
VMwareLiveMigrateDataobjectImplement pre live-migration checks
Implement methods for selecting target ESX host and datastore
Ensure CI coverage for live-migration
Update support-matrix
Dependencies¶
None
Testing¶
The VMware CI will provision two nova-computes and will execute the live migration tests from tempest.
Documentation Impact¶
The feature support matrix should be updated to indicate that live migration is supported with the VMware driver.
References¶
http://pubs.vmware.com/vsphere-60/topic/com.vmware.wssdk.apiref.doc/vim.VirtualMachine.html#relocate
History¶
Release Name |
Description |
|---|---|
Newton |
Introduced |
Ocata |
Reproposed |
Pike |
Reproposed |
Queens |
Reproposed |
Rocky |
Reproposed |
