Hi, I seem to read conflicting views on whether turning on tcp_syncookies is a good or bad thing. The docs mention this syncookies seriously violate TCP protocol, do not allow to use TCP extensions, can result in serious degradation of some services (f.e. SMTP relaying), visible not by you, but your clients and relays, contacting you Can someone elaborate on this ? Also, Dan Bernstein has a page on syncookies which alludes to some unanswered questions with some prominent linux developers http://cr.yp.to/syncookies.html -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/