Dropless, kernel bypass tcpdump on ExaNICs

ls -al libpcap.so.1
lrwxrwxrwx. 1 fischer fischer 17 May 2 12:59 libpcap.so.1 -> libpcap.so.1.11.0
[fischer@centos7 $ LD_LIBRARY_PATH=. ldd /usr/sbin/tcpdump
linux-vdso.so.1 => (0x00007ffca27aa000)
libcap-ng.so.0 => /lib64/libcap-ng.so.0 (0x00007f5327968000)
libcrypto.so.10 => /lib64/libcrypto.so.10 (0x00007f5327505000)
libpcap.so.1 => ./libpcap.so.1 (0x00007f53272b7000)
libc.so.6 => /lib64/libc.so.6 (0x00007f5326ee9000)
/lib64/ld-linux-x86-64.so.2 (0x00007f5327b6e000)
libdl.so.2 => /lib64/libdl.so.2 (0x00007f5326ce5000)
libz.so.1 => /lib64/libz.so.1 (0x00007f5326acf000)
libnl-genl-3.so.200 => /lib64/libnl-genl-3.so.200 (0x00007f53268c9000)
libnl-3.so.200 => /lib64/libnl-3.so.200 (0x00007f53266a8000)
libpthread.so.0 => /lib64/libpthread.so.0 (0x00007f532648c000)
libm.so.6 => /lib64/libm.so.6 (0x00007f532618a000)
[fischer@centos7 $ sudo TCPDUMP_DEBUG=1 LD_LIBRARY_PATH=. /usr/sbin/tcpdump -i enp4s0
exa_create: Found 2 ExaNIC ports total
1) enp4s0 IP 10.0.0.1 Netmask 255.255.255.0 [10Gbps] [LINKUP]
2) enp4s0d1 IP 10.0.1.1 Netmask 255.255.255.0 [10Gbps] [LINKUP]
tcpdump: verbose output suppressed, use -v or -vv for full protocol decode
listening on enp4s0, link-type EN10MB (Ethernet), capture size 262144 bytes
07:01:12.788053 ARP, Request who-has 10.0.1.2 tell centos7, length 28
07:01:13.791121 ARP, Request who-has 10.0.1.2 tell centos7, length 28
07:01:14.792963 ARP, Request who-has 10.0.1.2 tell centos7, length 28
^C
3 packets captured
3 packets received by filter
0 packets dropped by kernel

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NEIO Systems, Ltd.

NEIO Systems, Ltd.

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