HELP!!! DummyNet causing machine dead!

[Maxim Konovalov]

On Tue, 14 Oct 2003, 14:50-0500, mzu at cs.uh.edu wrote:

>
> I have three Squid machines working together as a cache array.
> I used Dummynet to control the inter-cache bandwidth.
>
> My three squid is 10.12.0.1, 10.12.0.2 and 10.12.0.3
>
> I used the following commands to create pipes in each squid
> For example, in Squid1:
> ipfw add pipe 1 IP from 10.12.0.1 to 10.12.0.2 out
> ipfw add pipe 2 IP from 10.12.0.1 to 10.12.0.3 out
> ipfw pipe 1 config bw 10Mbit/s queue 75Kbytes
> ipfw pipe 2 config bw 10Mbit/s queue 75Kbytes
>
> I have another program to change the bandwidth of each pipe every half an
> hour, with a lot of traffic going through the caches at the same time. So
> that the configeration for a pipe can change
>
> FROM: ipfw pipe 1 config bw 10Mbit/s queue 73Kbytes
>
> TO: ipfw pipe 1 config bw 2Mbit/s queue 25Kbytes
>
> Then in very short time, the machine is dead. I think the problem might
> because of the setting of "queue". But I don't know how much should be
> correct. I was using "bw x Mbit/s queue 6*x+13 Kbytes".
>
> Oh, when bandwidth change from 5M to 3M ,or 8M to 5M (smaller difference),
> the machines will run just fine with my 6*x+13 setting. Only steep jump
> like from 8M to 2M will always cause death.
>
> Please help me out!!! This is emergency!!!!

... and uname -a says?