datafill

Function

The datafill command configures padding characters in NQA test instance.

The undo datafill command removes the configured padding characters in NQA test instance.

Format

datafill fillstring

undo datafill

Parameters

Parameter	Description	Value
fillstring	Specifies the padding characters in NQA test packets.	The value is a string of 1 to 230 case-sensitive characters, with spaces supported. The special characters are supported.

Views

NQA view

Default Level

2: Configuration level

Usage Guidelines

Usage Scenario

In an NQA test, you need to simulate actual datagrams to obtain more accurate statistics. The datasize command can be used to set the size of the Data field. To differentiate packets sent from different test instances, add the specified characters to identify the test packets.

Prerequisites

Before running the datafill command, run the test-type command to specify the type of a test instance, which may be one of the following:

ICMP
UDP-tracert
UDP
UDP-jitter

Configuration Impact

After the datafill command is run, the following situations may occur:

If the length of the data packet sent from the test instance is shorter than the configured pad character, only the forepart of the pad character can be used.
If the length of the data packet sent from the test instance is shorter than the configured pad character, the pad character is repeated in sequence until the data packet is completely padded.

For example, the pad character is set to abcd. If the length of the test packet is 3, only abc is used to pad the test packet. If the length of the test packet is 6, abcdab is used to pad the test packet.

Payload filling modes in test cases may vary with different test types.

Test Type	Payload Padding Mode
ICMP	The character string specified by datafill is used to circularly fill in the payload from the 29th byte. That is, the datafill configuration is valid only when the value of datasize is larger than 28.
UDP-tracert	The character string specified by datafill is used to circularly fill in the payload from the 12th byte. That is, the datafill configuration is valid only when the value of datasize is larger than 12.
UDP	The first byte in the payload is 02, and the subsequent bytes are circularly padded with the string specified in the datafill command.
UDP-jitter	When datasize is set to 172, the first 100 bytes in the payload are fixed, and the subsequent bytes are circularly filled by the field specified by datafill. When datasize is set to another value, the payload is filled in by fixed fields. The configuration of datafill becomes invalid.

Precautions

The pad character of a running test instance cannot be changed.

Example

# Set the padding characters of the test named admin udp to "abcd".

<sysname> system-view
[sysname] nqa test-instance admin udp
[sysname-nqa-admin-udp] test-type udp
[sysname-nqa-admin-udp] datafill abcd