I have 4 computers 2 winxp pro and 2 linux

1 slackware for instance is 192.168.0.1 and second is 192.168.0.2

when trying to scan localhost udp ports it reveals nicely

or if i do from localhost to specify 192.168.0.1 or 192.168.0.2 from its computer it reveals nicely.

if i want to scan 192.168.0.2 from 192.168.0.1 (both linux machines)for udp for instance

nmap -sU 192.168.0.2 -v
i get
Increasing send delay for 192.168.0.2 from 0 to 50 due to max_successful_tryno increase to 4

Increasing send delay for 192.168.0.2 from 400 to 800 due to 11 out of 11 dropped probes since last increase.

And on Win boxes all UDP ports shows open

how to fix this?

Thanks!

Do you have some sort of firewall installed which enables ICMP filtering?