2eba495e22
TripleO project has been retired[1]. Remove the migration tool implemented specifically for TripleO deployments. Change-Id: I32775a0aa963b65a3900a87f28a88ab63901a8a0
41 lines
1.3 KiB
ReStructuredText
41 lines
1.3 KiB
ReStructuredText
Migration from ML2/OVS to ML2/OVN
|
|
=================================
|
|
|
|
Proof-of-concept ansible script for migrating an OpenStack deployment
|
|
that uses ML2/OVS to OVN.
|
|
|
|
Prerequisites:
|
|
|
|
1. Ansible 2.2 or greater.
|
|
|
|
2. ML2/OVS must be using the OVS firewall driver.
|
|
|
|
To use:
|
|
|
|
1. Create an ansible inventory with the expected set of groups and variables
|
|
as indicated by the hosts-sample file.
|
|
|
|
2. Run the playbook::
|
|
|
|
$ ansible-playbook migrate-to-ovn.yml -i hosts
|
|
|
|
Testing Status:
|
|
|
|
- Tested on an RDO cloud on CentOS 7.3 based on Ocata.
|
|
- The cloud had 3 controller nodes and 6 compute nodes.
|
|
- Observed network downtime was 10 seconds.
|
|
- The "--forks 10" option was used with ansible-playbook to ensure
|
|
that commands could be run across the entire environment in parallel.
|
|
|
|
MTU:
|
|
|
|
- If migrating an ML2/OVS deployment using VXLAN tenant networks
|
|
to an OVN deployment using Geneve for tenant networks, we have
|
|
an unresolved issue around MTU. The VXLAN overhead is 30 bytes.
|
|
OVN with Geneve has an overhead of 38 bytes. We need the tenant
|
|
networks MTU adjusted for OVN and then we need all VMs to receive
|
|
the updated MTU value through DHCP before the migration can take
|
|
place. For testing purposes, we've just hacked the Neutron code
|
|
to indicate that the VXLAN overhead was 38 bytes instead of 30,
|
|
bypassing the issue at migration time.
|