H3C Technologies H3C S5560 Series Switches - Manual (Page 134)

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Configuring fast forwarding
Overview
Fast forwarding reduces route lookup time and improves packet forwarding efficiency by using a
high-speed cache and data-flow-based technology. It identifies a data flow by using the following fields:
source IP address, source port number, destination IP address, destination port number, and protocol
number. After the first packet of a flow is forwarded through the routing table, fast forwarding creates an
entry for the flow and uses the entry to forward subsequent packets of the flow.
Fast forwarding can process fragmented IP packets, but it does not fragment IP packets.
Configuration procedure
To configure fast forwarding:
Step Command Remarks
1. Enter system view. system-view N/A
2. Enable fast-forwarding
load sharing.
ip fast-forwarding load-sharing
By default, fast-forwarding load
sharing is enabled.
3. Configure the aging time of
fast forwarding entries. ip fast-forwarding aging-time
aging-time By default, the aging time is 30
seconds.
Displaying and maintaining fast forwarding
Execute display commands in any view and reset commands in user view.
Task Command
Display fast forwarding table information.
display ip fast-forwarding cache [ ip-address ] [ slot
slot-number ]
Display fast forwarding table information about
fragmented packets. display ip fast-forwarding fragcache [ ip-address ]
[ slot slot-number ]
Display the aging time of fast forwarding entries. display ip fast-forwarding aging-time
Clear fast forwarding table information. reset ip fast-forwarding cache [ slot slot-number ]