Traceroute

Contents

• Introduction and Overview
• *Commands
  • TraceRoute

Introduction and Overview

In order to debug the connectivity of hosts using the Internet protocols, the UDP requests with increasing TTL values can be used to ascertain the route between hosts and the quality of the connection between us and the destinarion. The TraceRoute issues these requests and displays the results.

*Commands

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*TraceRoute

Send probe packets to network hosts to identify a route

Syntax

*TraceRoute [-d] [-r] [-n] [-v] [-m <ttl>] [-q <count>] [-p <port>] [-s <address>] [-t <tos>] [-w <wait>] <host> [<packetsize>]

Parameters

-d	-	Set the SO_DEBUG option on the socket being used.
-r	-	Bypass the normal routing tables and send directly to a host on an attached network. If the host is not on a directly-attached network, an error is returned. This option can be used to ping a local host through an interface that has no route through it.
-n	-	Numeric output only. No attempt will be made to lookup symbolic names for host addresses.
-v	-	Verbose output. ICMP packets other than TIME_EXCEEDED and UNREACHABLE that are received are listed.
-m <ttl>	-	Specifies the maximum TTL value that will be used.
-q <count>	-	Specify the number of probes per TTL value. (default is 3)
-p <port>	-	Specifies the UDP port base number to use. Queries will be send on ports starting at this base, up to the number of hops specified. If something on the route uses this port-range, it will be necessary to change it. (default is 33434)
-s <address>	-	Specifies the source address to use, where multiple interfaces are in use.
-w <time>	-	Specifies the time in seconds between probes (default is 3)
<packetsize>	-	Specifies the number of data bytes to be sent. (default is 38)
<host>	-	Host name to find the route to.

Use

The TraceRoute command is used to identify the route taken by packets to reach a host. Attempts are made to contact the host with increasing TTL values, resulting in hosts along the way responding with 'time exceeded' messages. These messages are identified and used to provide information on the route taken.

Example

*TraceRoute bighost.distantcorp.net

Related APIs

None

Document information

Maintainer(s):	RISCOS Ltd <developer@riscos.com>
History:	Revision Date Author Changes 1 ROL Initial version
Disclaimer:	Copyright © Pace Micro Technolgy plc, 2002. Portions copyright © RISCOS Ltd, 2002. Published by RISCOS Limited. No part of this publication may be reproduced or transmitted, in any form or by any means, electronic, mechanical, photocopying, recording or otherwise, or stored in any retrieval system of any nature, without the written permission of the copyright holder and the publisher, application for which shall be made to the publisher.