[ovs-discuss] [dpdk-ovs]VXLAN encapsulation exceeds the MTU of dpdk port .

[Dongjun]

On 2015/6/30 23:01, gowrishankar wrote:
> On Thursday 25 June 2015 01:31 PM, Dongjun wrote:
>> As following topology, two VMs communicate via VXLAN tunnel.
>> TCP pkts may be droped for exceeding the MTU of host DPDK port in br2.
>> Now I can change the VMs' MTU from default to smaller to accommodate 
>> the traffics, it works well.
>>
>> The way I have not find to change mtu of DPDK phy port, is there a 
>> blueprint for supporting this by ovs, like "ovs-appctl 
>> netdev-dpdk/set-xxx" or another way?
>>
>>         Host1                  |                     Host2
>>                     (l-ip)-   L3    -(r-ip)
>> -----   -----        -----     |     -----       -----  ----- -----
>> |VM1| --|br1|Vxlan --|br2|DPDK---DPDK|br2|--Vxlan|br2|--|br1|--|VM2|
>> -----   -----        -----     |     -----       -----  ----- -----
>
> There are two br2 bridge on Host2. It is intentional ?
>
> Btw, I am trying on same page but could not simplify the vm-vxlan-dpdk 
> working within "single" bridge case,
> may be that I am yet to find right flow rules to handle vhost-user, 
> vxlan and dpdk ports.
> I hope you are using patch port between two bridges. Would you really 
> need it ?
>
>
> Regards,
> Gowri Shankar
>> _______________________________________________
>> discuss mailing list
>> discuss at openvswitch.org
>> http://openvswitch.org/mailman/listinfo/discuss
>
Thanks.
There is a redundant br2. I fix topology, add IPs and configuration, 
would you please see it again.

               Host1            |            Host2
6.0.0.1              7.0.0.1-  L3   -7.0.0.2             6.0.0.2
-----   -----        -----     |     -----       -----  -----
|VM1| --|br0|Vxlan --|br1|DPDK---DPDK|br1|--Vxlan|br0|--|VM2|
-----   -----        -----     |     -----       -----  -----

Host1:
#Bridges and Ports:
ovs-vsctl add-br br0 -- set bridge br0 datapath_type=netdev
ovs-vsctl add-port br0 vhost-user-1 -- set interface vhost-user-1 
type=dpdkvhostuser ofport_request=1
ovs-vsctl add-port br0 vxlan-1 -- set interface vxlan-1 type=vxlan 
ofport_request=100 options:remote_ip=7.0.0.2

ovs-vsctl del-br br1
ovs-vsctl add-br br1 -- set bridge br1 datapath_type=netdev
ovs-vsctl add-port br1 dpdk0 -- set interface dpdk0 type=dpdk 
ofport_request=1

ifconfig br1 7.0.0.1/24

#Flows:
ovs-ofctl add-flow br0 priority=5,ip,nw_dst=6.0.0.1,action=output:1
ovs-ofctl add-flow br0 priority=5,ip,nw_dst=6.0.0.2,action=output:100
ovs-ofctl add-flow br0 priority=0,action=NORMAL

ovs-ofctl add-flow br1 priority=5,ip,in_port=LOCAL,action=output:1
ovs-ofctl add-flow br1 priority=5,ip,in_port=1,action=output:LOCAL
ovs-ofctl add-flow br1 priority=0,action=NORMAL


Host2:
#Bridges and Ports:
ovs-vsctl add-br br0 -- set bridge br0 datapath_type=netdev
ovs-vsctl add-port br0 vhost-user-1 -- set interface vhost-user-1 
type=dpdkvhostuser ofport_request=1
ovs-vsctl add-port br0 vxlan-1 -- set interface vxlan-1 type=vxlan 
ofport_request=100 options:remote_ip=7.0.0.1

ovs-vsctl add-br br1 -- set bridge br1 datapath_type=netdev
ovs-vsctl add-port br1 dpdk0 -- set interface dpdk0 type=dpdk 
ofport_request=1

ifconfig br1 7.0.0.2/24

#Flows:
ovs-ofctl add-flow br0 priority=5,ip,nw_dst=6.0.0.2,action=output:1
ovs-ofctl add-flow br0 priority=5,ip,nw_dst=6.0.0.1,action=output:100
ovs-ofctl add-flow br0 priority=0,action=NORMAL

ovs-ofctl add-flow br1 priority=5,ip,in_port=LOCAL,action=output:1
ovs-ofctl add-flow br1 priority=5,ip,in_port=1,action=output:LOCAL
ovs-ofctl add-flow br1 priority=0,action=NORMAL