Creating Ovs Flows - Chelsio Communications Terminator Series Installation And User Manual

Chapter XXI. OVS Kernel Datapath Offload
3.2.

Creating OVS flows

It is mandatory to specify L2 Ethernet Type (dl_type) to offload OVS flows. There are two types
of flows:
•
exact-match: Protocol and 4-tuple are mandatory to create an exact-match flow. ~0.5 million
exact-match flows can be offloaded.
•
wild-card: If any of 4-tuple and protocol are absent, wild-card flow is created. 496 wild-card
flows can be offloaded.
T5/T6 SO adapters do not support exact-match flows. Up to 494 wild-card flows are
Note
supported.
Examples
3.2.1.1. Generic Flows
Below are few example OVS Flows with the following filterMode and filterMask combination:
filterMode = fragmentation,ethertype,protocol,tos,port
filterMask = fragmentation,ethertype,protocol,tos,port
•
Wild-card flow to drop incoming packets on first port:
[root@host~]# ovs-ofctl add-flow br0 in_port=1,dl_type=0x800,action=drop
•
Wild-card flow to switch ARP packets (L2 EtherType=0x0806) on 1
[root@host~]# ovs-ofctl add-flow br0
in_port=1,dl_type=0x0806,action=output:2
•
Wild-card flow to switch TCP packets (L3 proto=6) on 1
and destination MAC addresses:
[root@host~]# ovs-ofctl add-flow br0 in_port=1,dl_type=0x800,
nw_proto=6,action=mod_dl_src:00:07:43:28:E4:50,
mod_dl_dst:00:07:43:44:64:50,output:2
•
Exact-match flow to drop matching 4-tuple traffic:
[root@host~]# ovs-ofctl add-flow br0
in_port=1,dl_type=0x800,nw_proto=6,nw_src=10.1.1.66,tp_src=11000,nw_dst=10.1
.1.58,tp_dst=11000,action=drop
Chelsio Unified Wire for Linux
st
port to 2
st nd
port to 2 port by rewriting source
nd
port:
304