ntx_dloop Command

Commands Reference, Volume 4

ntx_dloop Command

Purpose

Performs a direct memory access (DMA) loopback test for the Network Terminal Accelerator (NTX).

Syntax

ntx_dloop [ -c ] [ -q ] [ -d Device ] [ -h ] [ -l Rate ] { -n [ Blocks ] | -t [ Time ] } [ -r | -s BlockSize ]

Description

Attention: You must use the kill signal to stop this program. Do not use the kill -9 command to close this program as the channel will not be closed properly.

The ntx_dloop command performs a DMA loopback test with the Network Terminal Accelerator diagnostic on an adapter. The loopback test does the following:

Sends a block of data to the adapter.
Reads the data from the adapter.
Compares the data it reads against the original data.

Flags

-c	Disable data verification. The application does not check that the data block read from the adapter matches the data block sent to adapter. The default is to verify the data.
-d Device	Identifies the adapter raw device file name. By default, the /dev/rhp0 file is used.
-h	Gets the file descriptor for the adapter from standard input. This flag is only useful if you are running the command using the execve subroutine. As a result of the way the shell handles redirection, command lines of the type `ntx_dloop ... -h < /dev/rhp0` do not work.
-l Rate	Sets the data throughput limit. You can use this flag to limit the use of the host adapter interface. Specify the Rate value in characters per section. The default value is 40,000.
-n Blocks	Specifies the number of data blocks to send before terminating. By default, data blocks are sent for 30 seconds. You cannot use this flag with the -t flag.
-q	Runs the command quietly. By default, the command reports test results to standard output. If you specify the -q flag, only errors are reported.
-r	Varies the block sizes. When you specify this flag, the ntx_dloop command sends random blocks to the adapter. The block size varies from 1 to 512 blocks. You cannot use this flag with the -s flag. By default, the command uses a block size of 512.
-s BlockSize	Fixes the block size. The BlockSize parameter specifies the size of the blocks to use with the command. You can specify any value between 1 and 512. You cannot use this flag with the -r flag.
-t Time	Sets the program execution time. The Time variable specifies the length of time in seconds to loop before stopping. By default, the loop runs for 30 seconds. You cannot specify this flag with the -n flag.

Exit Status

This command returns the following exit values:

0	Successful completion.
>0	An error occurred.

Security

Access Control: You must have root authority to run this command.

Auditing Events: N/A

Examples

To run the DMA loopback on the default device for 3 minutes, do the following:

ntx_dloop -rt 180

This command runs using random block sizes and displays the result on standard output.

Files

/usr/bin/ntx_dloop	Contains the ntx_dloop command.
/dev/rhp0	Default NTX raw device file name.

Related Information

The /dev/rhp file.

Network Terminal Accelerator Overview in AIX Versions 3.2 and 4 Asynchronous Communications Guide.