if-match tcp

Function

The if-match tcp command configures a matching rule based on the SYN Flag in the TCP packet header in a traffic classifier.

The undo if-match tcp command deletes a matching rule based on the SYN Flag in the TCP packet header in a traffic classifier.

By default, a matching rule based on the SYN Flag in the TCP packet header is not configured in a traffic classifier.

Format

if-match tcp syn-flag { syn-flag-value | ack | fin | psh | rst | syn | urg }

undo if-match tcp syn-flag

Parameters

Parameter	Description	Value
syn-flag	Specifies the SYN Flag in the TCP packet header.	-
syn-flag-value	Specifies the SYN Flag in the TCP packet header.	The value is an integer that ranges from 0 to 63.
ack	Indicates that the SYN Flag type in the TCP packet header is ACK.	-
fin	Indicates that the SYN Flag type in the TCP packet header is FIN.	-
psh	Indicates that the SYN Flag type in the TCP packet header is PSH.	-
rst	Indicates that the SYN Flag type in the TCP packet header is RST.	-
syn	Indicates that the SYN Flag type in the TCP packet header is SYN.	-
urg	Indicates that the SYN Flag type in the TCP packet header is URG.	-

Views

Traffic classifier view

Default Level

2: Configuration level

Usage Guidelines

Usage Scenario

You can run the if-match tcp command to classify packets based on the SYN Flag in the TCP packet header so that the device processes packets matching the same traffic classifier in the same manner.

Prerequisites

A traffic classifier has been created using the traffic classifier command in the system view.

Precautions

If you run the if-match tcp command in the same traffic classifier view multiple times, only the latest configuration takes effect.

Example

# Configure a matching rule based on the SYN Flag of psh in the traffic classifier c1.

<HUAWEI> system-view
[HUAWEI] traffic classifier c1 operator and
[HUAWEI-classifier-c1] if-match tcp syn-flag psh