Differences between ovs-ofctl and ovs-dpctl

Basically, ovs-ofctl is used to look up for the actual flow table entries. And, ovs-dpctl can be used to see what is inside of the OVS’s kernel table, which can be considered as flow table, but OVS kernel module actually does not speak OpenFlow, i.e., it doesn’t handle OpenFlow messages.

The number of entries retrieved by ovs-ofctl and ovs-dpctl can be different. That is because only the matched entries in user-space are copied to the kernel-space. More details may be found in the OVS official website.

From the original post.
ovs-ofctl dump-flows” prints OpenFlow flow table entries.

ovs-dpctl dump-flows” is different.

As the manpage says:

This command is primarily useful for debugging Open vSwitch. The flow table entries that it displays are not OpenFlow flow entries. Instead, they are different and considerably simpler flows maintained by the Open vSwitch kernel module.

In a little more detail, the flows that ovs-dpctl prints are always exact-match. They reflect packets that have actually passed through the system in the last 5 seconds or so.

If you want to know what OpenFlow sees, use ovs-ofctl. If you want to verify that the OpenFlow flows are being implemented in the way you expect, ovs-dpctl is the right tool.

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