Duplicate (DUP)! ping packet cause
Hey Im running RedHat 9.0 with a 2.4.2 kernel. I have two computers each with a Micronet wireless card with a ADMTEK 8211 chip with the latest drivers and I noticed that if I set one or both onto auto frequency so that the card switched through the frequencies preiodically - it comes up in the kernel messages like:
set channel 1
set channel 2
set channel 3 ...
I found the network perfromance it really poor but the most interesting thing is that when trying to ping the other computer it would not work at first and then when the two computers both got to the same frequencies a ping request would get through but then the computer that sent the request would receive multiple duplicate replies (all have the same icmp sequnce number) sometimes up to 12 replies. I ran Ethereal to look at the packets and the intresting thing is apprenetly the first computer only sent one ping request packet for a single ICMP seq # but the second computer received usally about four request with the same ICMP seq #, sending a reply back for each one. But then computer one would not receive just four replies back but would often receive double the amount of replies or sometimes four times as much.
To fix this problem I can just set both cards to the same frequency but I was wondering if anyone knew what might be the cause of the duplicate replies and diffrent number of ping requests on each of the computers for the same ICMP seq #. One thought is maybe the computer with the wireless NIC set to auto freq is stuffing up the packet sending, so rather then just sending one request its sending multiple and the same as when the relies come back, rather then just processing four its duplicating them somehow.
Anyone elses thoughts on this would be much appreciated as it has become a little sidetrack to a project I am doing at the moment at university
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