FreeBSD 6.0 Buffer Overrrun System Crash

[John B. Wood]

Hello, everyone.  Several months ago I reported problems I was having in 
obtaining a stable bridging with Dummynet platform(Dell Dimension 3000) 
as a result of a receive buffer overrun on the em0 interface.  Instead 
of using Dummynet pipes to set up a controlled packet loss (25%) 
scenario I tried bridging and IPFW without Dummynet as follows:

ipfw add 100 prob 0.25 deny ip from any to any bridged
ipfw add 200 allow ip from any to any bridged

After several minutes of operating as expected the system crashes with 
the kernel message "em0: RX overrun" and the system has to be rebooted.  
This is the same error I got using Dummynet.  I also tried John 
Nielsen's configuration (cf this mailing list 4/7/06) to no avail.  Does 
anyone have a fix?  Thanks for your time and comment. Sincerely,

-- 
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