Bro with PF_RING receive repeating data packets

Hi all,
Recently I have some problems with Bro and PF_RING in cluster.
On my server, when I have less than 32 worker threads(rings), everything is okay, but when I use worker threads more than 32, pf_ring start to receive repeating data packets. For example, rings less than 32, I send 400000 packets to server and pf_ring info in /proc shows there is 400000 packets in rings, but when rings greater than 32, I can get 800000 packets when 33 rings and 1200000 packets when 34 rings and so on.
I guess if there is some rules that a pf_ring or a bro cluster can only support less than 32 rings or worker threads on a server or some other reasons?
Any insight would be helpful.

That sounds like an issue with PF_Ring. I would check their documentation and mailing list to see if they only support 32 rings.


Hi all
there is a limit to the number of sockets in a pf_ring kernel cluster,
it used to be 32, now I increased it to 64 which I guess should be enough.


Hi all,
Thanks for your reply.
I found a definition in kernel/linux/pf_ring.h in PF_RING source code. The “CLUSTER_LEN” define the maximum of sockets a cluster can holds.
Now Im sure it is a issue with PF_RING. And I also increased "CLUSTER_LEN" to 64 and it seems like everything is okay. But Im still confuse about why the limit set to 32 and whether it is right to modify the source code. Will it affect the stability of PF_RING and Bro?


Hi Li,
    I met the same problem as you. Have you solved it? I also wonder whether modifying this macro definition CLUSTER_LEN correct, and whether it will affect stability of the system, did you get any idea after this reply?

I had this issue previously. Probably best to just move from pfring to AF Packet ( That is what fixed it for me … and gave me a much better performance.

There is also a plugin in development for DPDK (, which has the potential to be even better, but this plugin is still in early development, I think.