I am getting lot of duplicate packets when i ping from host to host or from gusers on different hosts:
64 bytes from 10.0.58.192: icmp_seq=169 ttl=64 time=0.930 ms
64 bytes from 10.0.58.192: icmp_seq=169 ttl=64 time=1.073 ms (DUP!)
64 bytes from 10.0.58.192: icmp_seq=170 ttl=64 time=1.277 ms
64 bytes from 10.0.58.192: icmp_seq=170 ttl=64 time=1.337 ms (DUP!)
64 bytes from 10.0.58.192: icmp_seq=171 ttl=64 time=1.170 ms
64 bytes from 10.0.58.192: icmp_seq=171 ttl=64 time=5.017 ms (DUP!)
64 bytes from 10.0.58.192: icmp_seq=172 ttl=64 time=3.843 ms
64 bytes from 10.0.58.192: icmp_seq=172 ttl=64 time=3.920 ms (DUP!)
That happens:
- if you ping a broadcast address, because you send one ping and get many answers back.
- if two or more systems have the same IP and both send an answer back.
- if your NIC is in promiscious mode and you have a not so smart switch (or hub) which sends the ping also back to the pinging system.
- if you bridging 2 vNICs/pNICs
Workaround:
If you connect 2 teaming pNICs in 2 different swithes (not smart enough).
Change pNIC teaming on vSS to: Router based on IP hash or Explicit fileover order.
If you choose IP hash when connection going to same switch, do not gorget activate LAG on the switch, otherwise use Explicit fileover order.
Router based on source MAC hash or Router based originating port ID will not work in this situation.