Owner's Manual

Exceptions

This section describes the constraints of OpenFlow.

• Dell Networking switches can operate as Hybrid switches (switches running OpenFlow and legacy

functions simultaneously). You cannot enable Legacy functionality (switching and routing) on OF

ports or OF virtual local area networks (VLANs), as these interfaces are controlled by an OpenFlow

controller and are not available.

• Stacking of OpenFlow switches is not supported for the S4810, S4820T, S6000, or MXL switches. If

you configure stacking but disabled it in preparation for future stacking, the stack unit number must

be zero to enable OpenFlow on S4810, S4820T, S6000, or MXL switches.

• For OF ports and OF VLANs, the VLAN IDs used for OpenFlow must be unique; the VLAN IDs cannot

be used for legacy functionality on the same switch.

• Dell Networking does not recommend using global spanning tree protocol (STP) instances on ports

with both legacy VLANs and OF VLANs.

• Transport layer security (TLS) connections are not supported.

• Because controllers typically run their own version of link layer discovery protocol (LLDP), disable

legacy LLDP on OF ports.

• To avoid session timeout issues if you change the system clock, you must disable and re-enable all

existing OF instances.

• Emergency flows are not supported.

• Packet buffering is not supported.

• Data center bridging (DCB) and Internet small computer system interface (iSCSI) are not supported on

OpenFlow interfaces.

• The following packet types can only be copied to the controller and cannot be forwarded from a

physical switch port:

– STP BDPU

– LLDP

– GVRP

– ARP Replies

– 802.1x frames

– untagged broadcast packets received on an OF port

ACL Flow Exceptions

• Flooding (action “output=all” or “output=flood”) is supported on S4810, S4820T, S6000, and MXL

switches. Support for this command on the Z9000 was introduced in version 9.4(0.0).

• By default, ACL flows override flows installed in the L2 or L3 tables.

• Address resolution protocol (ARP) opcode, sender IP, and target IP matching are not supported.