under heavy load dccd cannot answer dccproc ?

Vernon Schryver vjs@calcite.rhyolite.com
Tue Oct 23 18:01:23 UTC 2001


> From: Levent Serinol <lserinol@yahoo.com>

> ...
> > the kernel will allow, whichever is smaller.  What is the maximum
> > RCVBUF value for your system?
>
> udp_recv_hiwat 8192
> udp_max_buf 262144
> tcp_max_buf 1048576

those values look low for a system that wants to handle 700 UDP
requests/second for any single service, not only the DCC.

> ...
> > There must be some limit on the request rate to > defend against denial
> > of service attacks and or buggy clients (e.g. an infinite loop in the MTA).
> > What do you think the limit should be?  

> I agree with you on DOS attack and buggy clients.But
> can you make it customizable while compiling code or
> running dccd ?
> ...

I was dreading adding yet another argv switches for all of the rate
limiting parameters when in practice they'll almost never be changed.
Your notion of a compile-time switch would be fairly easy to implement.
I'll do that in the next version.

For now, you could edit dccd/dccd_defs.h to change the value of RL_SUB
and then rebuild dccd.
(I'll probably change the names of those values.)


Vernon Schryver    vjs@rhyolite.com



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