Dup! Ping problems

wizard · Jun 28, 2006, 12:53 PM

Hi,

i am having problems with my pfsense firewall. Sending an icmp echo request to our windows 2003 load balancer service (DNS cluster ip) results in DUP! pings.

ping 213.160.x.xx
PING 213.160.64.65 (213.160.x.xx) 56(84) bytes of data.
64 bytes from 213.160.x.xx: icmp_seq=1 ttl=128 time=4.85 ms
64 bytes from 213.160.x.xx: icmp_seq=1 ttl=128 time=4.98 ms (DUP!)
64 bytes from 213.160.x.xx: icmp_seq=2 ttl=128 time=0.781 ms
64 bytes from 213.160.x.xx: icmp_seq=2 ttl=128 time=0.905 ms (DUP!)
64 bytes from 213.160.x.xx: icmp_seq=3 ttl=128 time=0.803 ms
64 bytes from 213.160.x.xx: icmp_seq=3 ttl=128 time=0.929 ms (DUP!)

Do you have an idea what the problem maybe.

sullrich · Jun 28, 2006, 1:26 PM

You have a ethernet like loop somewhere. The firewall should not be seeing its packets twice.

wizard · Jun 28, 2006, 1:38 PM

It's really unusual my network cards are pointing in two different subnets. The problem only occurs when i try to ping our windows cluster i can't seem to see how my firewall could see each packet twice. But every second packet is a dup! tcpdump also shows that the seq numbers are different could it be an arp problem? At the moment i am lost.