H3C Technologies H3C S12500 Series Switches - Manual (Page 11)

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• Priority—Matching precedence of the flow entry. When a packet is matched against the flow table
and only the highest priority flow entry that matches the packet is selected.
• Counters—Counts of the packets or bytes that match the flow entry. The counters of flow entries for
S12500 switches are updated based on the packet count. The following types of packets are not
counted:
{
Packets that are sent to the controller.
{
Packets that match flow entries whose instruction sets include the Meter instruction.
• Instructions—A set of instructions that are executed when a packet matches the entry. These include
the following types:
{
Meter—Directs the packets to the specified meter to rate-limit of the packets.
{
Apply-Actions—Applies the specified actions in the action set immediately.
{
Clear-Actions—Clears all actions in the action set immediately.
{
Write-Actions—Modifies all actions in the action set immediately.
The instruction set associated with a flow entry contains a maximum of one instruction of each type.
The instructions of the set are executed in the order specified by this list above.
When the pipeline processing stops, the actions (such as forwarding packets or modifying packets)
in the action set of the packet are executed. An action set contains a maximum of one action of
each type.
• Timeouts—Maximum amount of idle time or hard time for the flow entry.
{
idle time—The flow entry is removed when it has matched no packets during the idle time. If it
has matched packets (except packets that are sent to the controller) during the idle time, the idle
time is updated.
H3C recommends that you set an idle time that is no less than 60 seconds. When there are
more than 1k flow tables on the switch, set an idle time that is no less than 300 seconds. You
can use the display openflow summary command to view the number of tables on the switch.
For more information about setting the idle time, see H3C VCF Controller help.
{
hard time—The flow entry is removed when the hard time timeout is exceeded, whether or not
it has matched packets.
• Cookie—Flow entry identifier specified by the controller.
OpenFlow pipeline
An OpenFlow instance on an S12500 switch contains only one flow table, so an S12500 switch do not
support the OpenFlow pipeline processing in the current software version.
The OpenFlow pipeline processing defines how packets interact with flow tables contained by a switch.
The flow tables of an OpenFlow switch are sequentially numbered, starting at 0. The packet is first
matched against flow entries of the first flow table, which is flow table 0. A flow entry can only direct a
packet to a flow table number that is greater than its own flow table number.
When a packet matches a flow entry, the OpenFlow switch updates the action set for the packet and
counters, and passes the packet to the next flow table. In the last flow table, the OpenFlow switch
executes all actions to modify packet contents and specify the output port for packet forwarding.