> Mike Branco wrote: > > Do SYN packets have any particular use?
Yes, a packet that has the SYN flag set in it is the first packet of a connection. When you see a packet with SYN set, it is coming from someone who's attempting to make a new connection to your computer. > Is there a way to deny any and all SYN packets altogether? ipchains -A input -j DENY -i eth0 -p tcp ! -y -l Meaning: --------- -A input = add this rule to the input chain -j DENY = deny all packets which are -i eth0 = coming in on eth0, the external nic -p tcp = and the packet is tcp ! -y = and the packet has the SYN flag set, -l = then log these denies to the syslog. But you probably wouldn't want to do that, unless you never expect inbound new tcp connections (You get those doing outbound active ftp). Regards, Matthew _______________________________________________ Leaf-user mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/leaf-user
