It's not relevant to DPDK at all. I was trying to put two NICs in a host to single subnet, and even w/o DPDK involved, the NICs didn't work properly. Googling turned out that one can't use multiple NICs in a Linux host in single subnet under the default, out of the box, configuration.
I guess many of subscribers in this mailing list should already be familar w/ the problem. But I describe how I've solved the problem below in the hope that it may be helpful to someone like me: If one wants such a network setup, one needs to tweak routing rules together w/ a few changes to the way ARP is handled. An interesting point here is one needs to set routing rules correctly in order to just get ARP replies work as intenteded, though ARP replies are not strictly relevant to the outgoing packets. Please refer to the following doc: https://access.redhat.com/solutions/30564 In summary, each NIC needs to have a separate routing table and a routing rule linking the table w/ the IP address of the NIC. I added arp_ignore = 1 together w/ arp_announce = 2 since other docs on the ARP flux problem suggests doing so. DoHyung 2019년 1월 2일 (수) 오후 9:38, Jay Rolette <[email protected]>님이 작성: > On Tue, Jan 1, 2019 at 4:05 AM DoHyung Kim <[email protected]> wrote: > >> It was a consequence of the well-known behavior of Linux kernel regarding >> ARP handling when multiple NICs are on the same subnet. >> > > What solution did you end up going with? > -- DoHyung Kim Fluidic Inc.
