3Com Switch 8800 Advanced Software V5 Configuration Guide

Configuring IPv6 TCP Properties 227
Configuring the Aging
Time for PMTU
After the MTU of the path from the source host to the destination host is
dynamically determined (refer to
“IPv6 PMTU Discovery” on page 219), the source
host sends subsequent packets to the destination host on basis of this MTU. After
the aging time expires, the dynamically determined PMTU is removed and the
source host re-determines an MTU to send packets through the PMTU mechanism.
The aging time is invalid for static PMTU.
Follow these steps to configure the aging time for PMTU:
Configuring IPv6 TCP
Properties
The IPv6 TCP properties you can configure include:
■ synwait timer: When a SYN packet is sent, the synwait timer is triggered. If no
response packet is received before the synwait timer expires, the IPv6 TCP
connection establishment fails.
■ finwait timer: When the IPv6 TCP connection status is FIN_WAIT_2, the finwait
timer is triggered. If no packet is received before the finwait timer expires, the
IPv6 TCP connection is terminated. If a FIN packet is received, the IPv6 TCP
connection status becomes TIME_WAIT. If other packets are received, the
finwait timer is reset from the last received packet and the connection is
terminated after the finwait timer expires.
■ Size of the connection-oriented socket buffer.
Follow these steps to configure IPv6 TCP properties:
To do... Use the command... Remarks
Enter system view system-view -
Configure a static PMTU for a
specified IPv6 address
ipv6 pathmtu ipv6-address [
value ]
Required
By default, no static PMTU is
configured.
To do... Use the command... Remarks
Enter system view system-view -
Configure aging time for
PMTU
ipv6 pathmtu age age-time Optional
10 minutes by default.
To do... Use the command... Remarks
Enter system view system-view -
Set the finwait timer of IPv6
TCP packets
tcp ipv6 timer fin-timeout
wait-time
Optional
675 seconds by default
Set the synwait timer of IPv6
TCP packets
tcp ipv6 timer syn-timeout
wait-time
Optional
75 seconds by default
Set the size of the IPv6 TCP
buffer
tcp ipv6 window size Optional
8 KB by default