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Subjectwant to randomly drop packets based on percent
Hey,

I'm using the 2.4.32 kernel with madwifi and iproute2 version
2-2.6.16-060323.tar.gz

I wanted to insert artificial packet loss based on a percent so i found:
network emulab qdisc could do it, so i compiled support into the kernel
and tried:
tc qdisc change dev eth0 root netem loss .1%

however i keep getting the error
RTNETLINK answer: Invalid argument

I am not sure how to go about solving this problem for now, so if anyone
has any suggestions i'd greatly appreciate it.

I really only need to drop random packets being forwarded through
ip_forward ... however randomly dropping any packet based on a % is
sufficient so I figured netem would be great.

So in the meantime I figured I would try to insert packet loss in
ip_forward.c by generating a random number and dropping based on that.
I could goto drop; depending on the number in the function int
ip_forward(struct sk_buff *skb)

But then I ran into the problem of properly seeding the random number
generator... srand(time(0)) is one way... however time() returns
seconds, therefore i would drop multiple packets in a single second if I
used this method which is very undesirable. What is the proper way to
generate a random number here?

Thanks!
George
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