Dell POWERCONNECT 6200 SERIES, Configuration Manual

Page: 55 / 176

Switching Configuration
55
Table 3-1 describes the
dos-control
keywords.
Table 3-1. DoS Control
CLI Examples
The commands shown below show how to enable DoS protection and view its status.
Example #1: Enabling all DOS Controls
console#configure
console(config)#dos-control sipdip
console(config)#dos-control firstfrag
console(config)#dos-control tcpfrag
console(config)#dos-control l4port
console(config)#dos-control icmp
console(config)#exit
Keyword Meaning
firstfrag Enabling First Fragment DoS prevention causes the switch to drop packets that
have a TCP header smaller then the configured Min TCP Hdr Size.
icmp ICMP DoS prevention causes the switch to drop ICMP packets that have a type
set to ECHO_REQ (ping) and a size greater than the configured ICMP Pkt Size.
l4port Enabling L4 Port DoS prevention causes the switch to drop packets that have
TCP/UDP source port equal to TCP/UDP destination port.
sipdip Enabling SIP=DIP DoS prevention causes the switch to drop packets that have a
source IP address equal to the destination IP address.
tcpflag Enabling TCP Flag DoS prevention causes the switch to drop packets that have
TCP flag SYN set and TCP source port less than 1024 or TCP control flags set to
0 and TCP sequence number set to 0 or TCP flags FIN, URG, and PSH set and
TCP sequence number set to 0 or both TCP flags SYN and FIN set.
tcpfrag Enabling TCP Fragment DoS prevention causes the switch to drop packets that
have an IP fragment offset equal to 1.