Open vSwitch Advanced Features Tutorial-202309031730

Summary

The notes for ovs-advanced.rst tutorial.

Terminology

• Open vSwitch
• OpenFlow
  • Flow
  • Table
  • Priority
  • action
  • resubmit
• OVS Actions
  • Load
  • Learn
  • strip_vlan
  • output
• OVS Fields
  • NXM_OF_VLAN_TCI
  • NXM_OF_ETH_DST
  • NXM_OF_ETH_SRC
  • NXM_OF_IN_PORT
  • NXM_OF_NX_REG0
• OVS Register
• Packets
  • reserved multicast protocols
  • IEEE 802.10 Spanning Tree Protocol(STP)

Notes

The tutorial shows the example how to use OVS flow table to implement a MAC-learning switch with VLAN trunk and access port.

Below is the overview of the OVS flow tables for this tutorial:

Consider to understand how OpenFlow flow table works before continue.

The tutorial use 5 tables for pipeline.

flowchart LR

table0[table 0 Admission Control]
--> table1[table 1 VLAN Input Processing]
--> table2[table 2 MAC+LAN Learning for Ingress Port]
--> table3[table 3 Look up Destination Port]
--> table4[table 4 Output Processing]

We can turn this pipeline into couple of questions:

1. How to drop packets in flow with?
   1. multicast source address
   2. reserved multicast protocols
   3. Spanning Tree Protocol(STP)
2. How to create a default drop flow?
3. How to create a flow with ovs action and what does action’s behavior?
   1. resubmit
   2. learn
   3. load
   4. strip_vlan
4. What is register of OVS?
   1. What is NXM_NX_REG0?
5. How to output packet in flow?
6. How to handle below packets in the pipeline?
   1. Multicast
   2. Broadcast
   3. Unicast
7. What does those OVS fields means?
   1. NXM_OF_VLAN_TCI
   2. NXM_OF_ETH_DST
   3. NXM_OF_ETH_SRC
   4. NXM_OF_IN_PORT
8. ovs-vsctl
   1. How to create port, interface, and bridge?
   2. How to show the tables and flow of bridge?
9. ovs-ofctl
   1. How to create flow?
10. How to test the flow table with ovs-appctl?

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References

• ovs-fields.7.txt

• ovs-actions(7) - Linux manual page

OpenFlow

• https://wiki.onosproject.org/display/ONOS/OpenFlow+1.5+Implementation
• openflow-switch-v1.5.1.pdf