HP MSR2000/3000/4000 Router Series Layer 3 - IP Services Configuration Guide

164
To enable TCP SYN Cookie:
Step Command Remarks
1. Enter system view.
system-view N/A
2. Enable SYN Cookie.
tcp syn-cookie enable The default setting is disabled.
Configuring the TCP buffer size
Step Command Remarks
1. Enter system view.
system-view N/A
2. Configure the size of TCP receive/send
buffer.
tcp window window-size
The default buffer size is 64 KB.
Configuring TCP timers
You can configure the following TCP timers:
SYN wait timer—TCP starts the SYN wait timer after sending a SYN packet. If no response packet
is received within the SYN wait timer interval, TCP fails to establish the connection.
FIN wait timer—TCP starts the FIN wait timer when the state changes to FIN_WAIT_2. If no FIN
packet is received within the timer interval, TCP terminates the connection. If a FIN packet is
received, TCP changes connection state to TIME_WAIT. If a non-FIN packet is received, TCP restarts
the timer, and tears down the connection when the timer expires.
To configure TCP timers:
Step Command Remarks
1. Enter system view.
system-view N/A
2. Configure TCP
timers.
Configure the TCP SYN wait timer:
tcp timer syn-timeout time-value
Configure the TCP FIN wait timer:
tcp timer fin-timeout time-value
By default:
The TCP SYN wait timer is 75
seconds.
The TCP FIN wait timer is 675
seconds.
Enabling sending ICMP error packets
Perform this task to enable sending ICMP error packets, including redirect, time-exceeded, and
destination unreachable packets.
ICMP redirect packets
A host that has only one default route sends all packets to the default gateway. The default
gateway sends an ICMP redirect packet to inform the host of a correct next hop by following these
rules:
{ The receiving and sending interfaces are the same.