Levent Serinol
lserinol@yahoo.com
Tue, 23 Oct 2001 10:35:38 -0700 (PDT)
> invoked. Are there any messages in your logs like > "xx requests/sec are too many"? yes. sorry I forgot to send it in my previous mail. here what it says : Oct 22 18:18:10 gemini dccd[14598]: [ID 803709 mail.notice] 53 requests/sec are too many from 32768 212.xxx.xxx.xxx,55920 > If not, you've found an upper bound on the performce > of fork()/exec(), > dccproc, dccd, or something else on your system. > > You might have simply overflowed the kernel socket > buffer. > 700 UDP packets is at least 140 KBytes. A burst of > 700 requests > after things were quiet would probably suddently > inflate the RTT, > and so each of the dccproc clients would have > quickly sent 3 > retransmissions. That would try to stuff 400 KBytes > into the > socket buffer. Dccd asks a socket buffer of 1 MByte > or whatever > 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 > 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 think > 700/second is far too > high for almost all installations, and if you really > need that rate, > I'll have to make the rate limit machinery > configurable. I'll be so glad. Best Regards, ===== Levent Serinol ICQ# : 9792343 #exclude <windows.h> "Trust me. I know what I'm doing." -- Sledge Hammer __________________________________________________ Do You Yahoo!? Make a great connection at Yahoo! Personals. http://personals.yahoo.com