3Com 10014298 manual IP Performance, Attributes

IP Performance 77

debugging command to output the debugging information to the console. In this way, you can view the detailed information of all DHCP packets on the console while applying for the IP address, thereby, conveniently locating the problem.

IP Performance	IP performance configuration includes:
	■	Configuring TCP Attributes
	■ Configuring Special IP Packet Transmission to the CPU
	■ Configuring L3 Broadcast Forwarding
	■ Displaying and Debugging IP Performance
	■	Troubleshooting IP Performance

Configuring TCP The TCP attributes that can be configured include:

Attributes

■synwait timer: When sending the syn packets, TCP starts the synwait timer. If response packets are not received before synwait timeout, the TCP connection will be terminated. The timeout of synwait timer ranges 2 to 600 seconds and it is 75 seconds by default.

■finwait timer: When the TCP connection state turns from FIN_WAIT_1 to FIN_WAIT_2, finwait timer will be started. If FIN packets are not received before finwait timer timeout, the TCP connection will be terminated. Finwait ranges 76 to 3600 seconds and it is 675 seconds by default.

■The receiving/sending buffer size of connection-oriented Socket is in the range from 1 to 32K bytes and is 4K bytes by default.

Perform the following configuration in System view.

Table 74 Configure TCP Attributes

Operation	Command
Configure synwait timer time for TCP	tcp timer syn-timeout time-value
connection establishment
Restore synwait timer time for TCP connection	undo tcp timer syn-timeout
establishment to default value
Configure FIN_WAIT_2 timer time of TCP	tcp timer fin-timeout time-value
Restore FIN_WAIT_2 timer time of TCP to	undo tcp timer fin-timeout
default value
Configure the Socket receiving/sending buffer	tcp window window-size
size of TCP
Restore the socket receiving/sending buffer	undo tcp window
size of TCP to default value

By default, the TCP finwait timer is 675 seconds, the synwait timer is 75 seconds, and the receiving/sending buffer size of connection-oriented Socket is 4K bytes.

Configuring Special IP In IP packet forwarding, redirection packets, TTL timeout packets, and route Packet Transmission to unreachable packets are often sent to CPU, which will notify the peer end for

the CPU further processing upon receiving them. Configuration errors and malicious assaults may cause CPU overload. In this case, to maintain normal system