Coordinating controller hybrid mode and OpenFlow switch settings

Supporting hybrid mode on OpenFlow switches

The OpenFlow configuration on individual HP switches must support the controller hybrid mode setting. Table Table 4 shows the correspondence between the hybrid mode configuration on the controller and the per-instance passive/active configuration on HP OpenFlow switches.

Hybrid mode support on ProVision switches

Hybrid Mode SettingsProVision OpenFlow Instance Configuration
Enabled (true)passive
Disabled (false)active

See the OpenFlow documentation for the specific switch.

See the latest OpenFlow documentation for HP switches for details on how to configure passive/active mode (where applicable) and for how such switches behave if they lose their control-plane connection to the controller.

Configuring controller settings to support hybrid mode

Network-related settings on the controller must agree with the controlled switches. Failure to achieve agreement between the controller’s network-related settings and the settings in the controlled switches might result in unpredictable network behavior. Table 5 lists the specific network-related controller settings that should agree with managed switches.

Controller settings to support hybrid mode

Controller Configurations ComponentKeyComments
com.hp.sdn.ctl.of.impl.ControllerManagerhybrid.modeEnable this setting if you want your controller to operate in hybrid mode (service restart required).

NOTE: Path Diag Tool will not work with flowmod strict mode or hybrid.mode = false or Path Daemon in hybrid-mode=false as Path Diag Tool was not designed to allow PDT to manipulate flow priority. age.multihop.links when set to true makes multihop.poll.interval valid. So whatever interval is set for this key becomes the polling interval for multi-hop links. Using polling interval can control how fast the multi-hop links need to be purged from controller if they are no longer active in the network. If age.multihop.inks flag is set to false then multi-hop links are not polled for their liveliness and never get purged from controller even if they have gone down.
age.multihop.linksFlag indicating whether multihop link aging is enabled. Enable this setting if there are switches in the network that are not controlled by the controller, but the topology across these switches must be visible to the controller. That is, if any controlled OpenFlow switches in the same OpenFlow instance are separated by non-OpenFlow switches, use this setting.

NOTE: Anytime user changes values for either age.multihop.links or multihop.poll.interval the "OpenFlow Link Discovery" app needs to be bounced so that those newly changed values take into effect.

com.hp.sdn.disco.of.node.impl.OfDhcpDiscoveryComponentdhcp.ageSet this value equal to or greater than your network’s DHCP lease time. Timeout (in minutes) for nodes learned via DHCP.
com.hp.sdn.disco.of.node.impl.OfArpDiscoveryComponentarp.ageOpenFlow end-host discovery via the ARP protocol. Timeout (in minutes) for nodes learned via ARP.
com.hp.sdn.disco.of.node.impl.OfIpDiscoveryComponentip.ageOpenFlow end-host discovery via the IP protocol. Timeout (in minutes) for nodes learned via IP.
learn.ipWhether or not the controller will discover nodes from all IP packets it receives.

To view or reconfigure any of the above controller configuration components, click on the component, then click on the Modify button. For more on this topic, see the "Configurations" section in chapter 2 of this guide.

Configuration components to modify for hybrid mode support

Configuration components to modify for hybrid mode support

NOTE: For information about version support for ip-control-table-mode command options, see HP VAN SDN Controller and Applications Support Matrix.

For information about version support for hardware-only mode, see HP VAN SDN Controller and Applications Support Matrix.

NOTE: OpenFlow 1.0 is the default version of OpenFlow for HP ProVision switches. OpenFlow does not allow the controller to optimize flow location in hardware tables. For concerns about line-rate data plane performance, configure all managed switches to use OpenFlow 1.0. Failure to properly configure the switch in this way might cause packet loss or other problems associated with high switch CPU utilization.

Uncontrolled switches in an OpenFlow Hybrid network are not visible to or controlled by the HP VAN SDN Controller. Uncontrolled switches are either controlled by another controller (outside the team) or not controlled at all (traditional networking). Traffic by such switches is independently managed.

The VAN SDN Controller Path Diagnostic Tool is useful only when hybrid mode is disabled. When hybrid mode is enabled, the controller does not monitor or direct all flows in the network. As a result, the path diagnostic tool (PathDiagnosticManager) does not have visibility into all flows on the network, and should not be used.