H3C Technologies H3C Intelligent Management Center - Manual (Page 62)

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{
Write-Metadata—Select Write-Metadata, and enter metadata.
{
Goto-Table—Select Goto-Table, and enter a flow table ID. The table ID must be larger than the
table ID of the flow entry. The flow entries of the last flow table do not have the Goto-Table
instruction.
Configuring actions
The Apply-Actions instruction specifies a sequence of actions to be immediately executed on a packet.
The action set of the packet is not affected when the action list is executed. The Write-Actions instruction
adds actions to the action set of a packet.
Action set
An action set is bound to each packet. Initially, the action set does not contain any actions. As the packet
is processed by flow tables, actions accumulate in the action set. A flow entry can use the Write-Actions
or Clear-Actions instruction to modify or clear the action set. The action set does not immediately change
contents of the packet after the packet is processed by a flow entry. After the packet is processed by a
flow entry that does not contain the Goto-Table instruction, the pipeline processing ends. Then the action
set of the packet is executed.
In an action set, each action type includes only one action. If the action set contains groups, actions in
each group are executed in order.
The actions in an action set or group are executed in this order:
1. Copy TTL Inwards
2. Pop VLAN/MPLS/PBB Tag
3. Push MPLS Tag
4. Push PBB Tag
5. Push VLAN Tag
6. Copy TTL Outwards
7. Decrement MPLS/IP TTL
8. Set MPLS TTL/IP TTL/Field
9. Set Queue
10. Group
11. Output
Action list
The Apply-Actions instruction modifies a packet by applying an action list to the packet. The actions in an
action list are the same as those in an action set, except that the actions in the action list immediately
modify the contents of a packet. Effects of the actions are cumulative. The actions are executed in the
order specified by the action list.
Table 7 shows the actions supported by an OpenFlow switch.
Table 7 Actions
Action Function
Output Send the packet out of a specified port.
Copy TTL Outwards
Copy the TTL from the next-to-outermost header to the outermost
header.