Deployment Guide

High Availability

This section describes OpenFlow (OF) protocol 1.0 and 1.3 support for High Availability (HA) on the C9000 Series.

NOTE: OpenFlow protocol is supported on chassis (LP) and Line Module (LM) ports. It is not supported on Port Extender (PE)

ports.

High availability (HA) is a collection of features that preserves system continuity by maximizing uptime and minimizing packet loss during

system disruptions. The C9000 Series switch has two route processor modules (RPMs), the primary RPM and the secondary RPM. The

primary RPM performs routing, switching, and control operations while the standby RPM monitors the primary RPM. If the primary RPM

fails, the standby RPM can assume control of the system without requiring a chassis reboot.

The OF handler running on Active RPM is active and the one running on the Standby RPM is standby. The Active OF handler initiates the

connection with the controller. During an RPM switchover, all flows from hardware, including L2, L3, and ACL, remain secure and a fresh

connection is initiated with the controller. RPM switchover is not hitless, however, traffic loss is minimized by the following.

During runtime, the standby RPM syncs with the active RPM:

• Standby RPM has all the configuration information for OF-ports, OF-VLANs, and OF-instance configuration via the replay mechanism

to the standby RPM.

• Standby RPM does not play any role in openflow protocol related to connections with controller and has no flow database.

During an RPM failover, the Standby RPM performs the following:

• Restores the critical configuration information such as, OF-Ports, OF-VLAN, and OF instance using the replay mechanism.

• Reconnects to the controller using the reconnect—timer command to become the new Active RPM.

• New Active RPM starts the recovery timer using the recover-timer command to recover all the flows from the controller and

resume the connection. All flows are replayed by the controller and the new active RPM reconciles the flows with all line cards.

• Reconnect and recover timers are configurable and provide a window for the reconnect and recover functions to execute during an

RPM failover event.

• At the end of the reconnect time any flows that are not reconciled are flushed out.

The following configuration example shows reconnect—timer and recover—timer configuration:

Dell#Dell#show openflow

Manufacturer : Dell

Hardware Desc : OpenFlow switch HW ver. 1.0

Software Desc : OpenFlow switch SW ver. 1.0 and 1.3

Capabilities : port,table,flow,queue

Actions : output,enqueue,strip-vlan,set-vlan,set-pcp,set-smac,

set-dmac,set-tos

Default VLAN : 0 (configured), 4091 (used)

Source Suppression : enabled

Reconnect Timer : 150

Recover Timer : 50

Dell#

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