Learn OpenStack · deploy/reference/decision-guides
Networking Decision Guide
Comparison
| Feature | OVN | Open vSwitch (OVS) | LinuxBridge |
|---|---|---|---|
| Recommended for | New deployments | Existing OVS users | Simple/small environments |
| Complexity | Medium | Medium-High | Low |
| Performance | High (kernel datapath) | High (kernel datapath) | Moderate |
| Distributed routing (DVR) | Native (built-in) | Supported (extra config) | Not supported |
| Hardware offload | Supported | Supported | Not supported |
| L3 HA | Native | Requires VRRP config | Requires VRRP config |
| Security groups | OVN ACLs (fast) | OVS conntrack | iptables (slower at scale) |
| DPDK support | Yes | Yes | No |
| Maintenance burden | Low (single control plane) | Higher (separate L3/DHCP agents) | Low |
| Upstream focus | Primary — active development | Maintenance mode | Maintenance mode |
| IPv6 | Full support | Full support | Full support |
Recommendation by Use Case
Production / New deployment → OVN
OVN is the recommended networking backend for all new OpenStack deployments as of 2025.1. It provides: - Distributed routing without extra configuration - Native L3 HA without VRRP - Single control plane (no separate L3, DHCP, or metadata agents) - Active upstream development and community focus
In globals.yml:
neutron_plugin_agent: "ovn"
Existing OVS deployment → Keep OVS
If you already run Open vSwitch, there's no urgent reason to migrate. OVS remains fully supported. Consider migrating to OVN during a major version upgrade if you want to reduce operational complexity.
In globals.yml:
neutron_plugin_agent: "openvswitch"
enable_neutron_dvr: "yes" # if distributed routing is needed
Dev/test or very simple environments → LinuxBridge
LinuxBridge is the simplest option. No OVS/OVN infrastructure needed. Good for single-node or small lab deployments where advanced networking features aren't required.
In globals.yml:
neutron_plugin_agent: "linuxbridge"
Migration Paths
| From | To | Path |
|---|---|---|
| LinuxBridge → OVN | Requires full neutron migration. Not a simple config change — plan a maintenance window and follow the upstream migration guide. | |
| OVS → OVN | Supported migration path documented upstream. Best done during a major version upgrade. Requires neutron DB migration. | |
| OVN → OVS | Not recommended. Possible but requires manual neutron reconfiguration and DB changes. |
Key rule: Pick your networking backend at initial deployment. Migrations are possible but non-trivial and require downtime.