Deployment Guide

Forwarding Features

Flow Failover

This feature provides failover support if a controller is unavailable. If the connection to a controller is lost, installed flows are retained and

used for forwarding traffic until they are updated. This feature is enabled by default but you can disable failover on individual instances by

using the use the no fail-mode secure command. If you disable failover, all flows to the unavailable controller are dropped. For more

information, refer to the fail-mode secure command.

Flow Misses

By default, flows that do not reach their intended destination (flow misses), are copied to the controller. To disable this feature on an OF

instance, configure the controller to drop flow misses instead of copying them to the controller by using the flow-misses drop

command. For more information, refer to the flow-misses drop command.

Default VLAN

In the previous version of OpenFlow, some packet types, such as untagged ARP broadcasts, received on an OF port could not be

forwarded from a physical port and could only be copied to the controller. To resolve this issue, assign a default VLAN to the OF ports

using the openflow vlan command. If you do not assign a VLAN, the software selects one when you create the first OF instance. The

default VLAN applies to all OF instances and can only be configured if you have not configured any OF instances. For more information,

refer to the

openflow vlan command.

Source Suppression

Source suppression prevents received packets from being transmitted from the ingress port. Source suppression is enabled by default and

is applied to all instances on the switch. If you disable source suppression, received packets can be transmitted from the ingress port.

NOTE

: If you disable source suppression, the following conditions apply:

• Dell Networking does not recommend enabling legacy features.

• You cannot enable Hybrid mode.

• If you install flows using OFPP_FLOOD or OFPP_ALL, traffic loops may occur. If you disable source suppression, Dell Networking

recommends that you do not install flows using these parameters.

For more information, refer to the src-suppression command.

VLAN Tag Removal

This feature allows an interface processor (IFP) action to remove the outer VLAN tag from a packet before sending it out of the egress

port. OpenFlow VLAN egress ports are now supported and flows with the strip-vlan action and an OF VLAN member port as the

egress port are accepted.

NOTE

: This feature is supported for OF egress ports only.

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