On Tue, 30 Oct 2007, Edinilson - ATINET wrote: > Since a week we could note a massive (and abnormal) smtp connections in our > XMail server (XMail 1.25 Win32 on Windows 2000 Server). > After many adjusts in XMail threads to support this "DDOS", we could note an > interesting thing: Windows 2000 Server does not support more than 1800 > threads (counting all kind, pop3 threads, smtp threads, mailer threads, > etc). > After +-1800 threads, XMail.exe is still there but not answering anymore. > > Could others XMail Win32 users confirm this value (1800) ?
It is *very* likely a VM space exhaustion due to the VM reservation that needs to be done for each thread stack. In Linux (and some Unixes in general) an `ulimit -s NNNN` can solve the problem, that has been there since the introduction of the NPTL library. In Windows, XMail uses the default system stack size, even because there no completely portable (over the whole Windows family, from NT, up) way to reduce it. In general, 1000+ threads should be *more* than enough. I suggest you to use some good Maps inside the server.tab file, so that connections gets dropped immediately. I noticed the increase of spammer activity too, on xmailserver.org. About little more than one year ago, I had about 2-3000 rejections at Maps level, whereas the last week I saw than jumping to more than 40K. Unfortunately, spammer's Mom is always pregnant. - Davide - To unsubscribe from this list: send the line "unsubscribe xmail" in the body of a message to [EMAIL PROTECTED] For general help: send the line "help" in the body of a message to [EMAIL PROTECTED]
