Flow Director doesn't work with fragmented packets

[thanhnv118]

Hi all,

We are trying to use flow-director to split data traffic to a VF in NIC X540-AT2 and we have successfully experimented this solution with packet ( MTU < 1500 ) . But with packet that bigger than MTU 1500 ( IP fragmentation breaks packets into smaller fragments ) , Flow Director doesn't work !!!!!

- Create VFs

#echo 1 > /sys/class/net/p7p2/device/sriov_numvfs

- Config Flow Director ( for queue_id 0 of VF 1 ) :

#ethool --config-ntuple p7p2 flow-type udp4 dst-ip 192.168.1.5 dst-port 2152 action 4294967296 (

 action = vf_id * 2^32 + queue_id )

Filter: 2045

       Rule Type: UDP over IPv4

       Src IP addr: 0.0.0.0 mask: 255.255.255.255

       Dest IP addr: 192.168.1.5 mask: 0.0.0.0

       TOS: 0x0 mask: 0xff

       Src port: 0 mask: 0xffff

       Dest port: 2152 mask: 0x0

       Action: Direct to queue 4294967296 

- OS : CentOS 7

We also change flow-type udp4 into ip4 , but it still doesn't work.

Could anyone give me some suggestions to solve it ??

Brgs,

thanhnv118

[Mike_Intel]

Hello thanhnv118,

Thank you for posting in Intel Ethernet Communities. 

For us to further check the issue, please tell us why are you doing this experiment? Are you designing a system with embedded X540-AT2?

If you have questions, please let us know. In case we do not hear from you, we will make a follow up after 3 workings days. Thank you.

Best regards,

Michael L.

Intel Customer Support Technicians

[thanhnv118]

Dear Michael,

Thank you for your reply,

I'm trying to split traffic between Linux user space and kernel space, so i use Flow Bifurcation mechanism as a guide : 

https://doc.dpdk.org/guides-17.05/howto/flow_bifurcation.html .

And my issue : with fragmented packets , VF doesn't have any packet .

Best regards,

thanhnv118

[Mike_Intel]

Hello thanhnv118,

For us to understand what you are doing and to route you to the right support if needed. Please clarify if you are designing a system to a software?

If you have questions, please let us know. In case we do not hear from you, we will make a follow up after 3 workings days. Thank you.

Best regards,

Michael L.

Intel Customer Support Technicians

[thanhnv118]

Hi Michael,

Thank you for your reply

Yep, I have a process (at server A ) send UDP packet size ( MTU > 1500) to card NIC 540-AT2( at server B).

I want to filter this packet with Flow director and I use tcpdump in VF but do not have any packets.

My question is very simple : How to filter fragmented packet with using Flow Director?

Brgs,

thanhnv118

[Mike_Intel]

Hello thanhnv118,

Base on your inquiry, we have specific forum for these issues and I will be transferring this thread for faster response. 

Best regards,

Michael L.

Intel Customer Support Technicians

[thanhnv118]

Dear Mr Michael,

Thank you for your support,

I hope you give me solution as soon as possible. 

Brgs,

thanhnv118

[CarlosAM_INTEL]

Hello, @thanhnv118:

Thank you for contacting Intel Embedded Comunity.

You should address your VF consultation as a reference to the channel listed on the following website:

https://bugs.dpdk.org/

Best regards,

@CarlosAM_INTEL.

[thanhnv118]

Hi CarlosAM,

Thank you for your support.

So i have a question : Does Intel Ethernet Flow director support fragmented packet filtering ???

Bgrs,

thanhnv118

[CarlosAM_INTEL]

Hello, @thanhnv118:

Thanks for your reply.

Based on your last communication, we suggest following the suggestion stated in our previous message, which is the proper way to answer this type of question. 

Best regards,

@CarlosAM_INTEL.