[clug] Re: Determining availability of a remote machine
kim.holburn at anu.edu.au
Thu Apr 3 19:38:16 EST 2003
At 5:47 PM +1000 2003/04/02, Jepri wrote:
>On 2003.04.02 17:43, Steve Jenkin wrote:
>>'traceroute' relies on the proper intermediate handling of expired
>>live', not ICMP ECHO (ping).
>>>From my (linux) manpage:
>> -I Use ICMP ECHO instead of UDP datagrams.
>> -p Set the base UDP port number used in probes
>> (default is 33434). Traceroute hopes that nothing
>> is listening on UDP ports base to base + nhops - 1
>> at the destination host (so an ICMP PORT_UNREACH-
>> ABLE message will be returned to terminate the
>> route tracing). If something is listening on a
>> port in the default range, this option can be used
>> to pick an unused port range
>>... .then listening for an ICMP "time exceeded" reply from a
>>Would be nice if it would use an designated TCP port, would work just
>>and could be 'jiggled' to go through various firewalls. [tcp:80/http
>>obvious default choice]
>This is already part of the ping standard. Try looking in your /etc/services file. It's almost always commented out.
Exactly what is it you're talking about? What is part of the ping standard? /etc/services has udp and tcp ports. What has that to do with ping?
>ping-pong 3010/udp # Telerate Workstation
>lsp-ping 3503/tcp # MPLS LSP-echo Port
>lsp-ping 3503/udp # MPLS LSP-echo Port
># Ping Pan <pingpan at juniper.net>
>pds 9595/tcp # Ping Discovery Service
>pds 9595/udp # Ping Discovery Service
Also your email has an odd header:
Cc: Warwick Mitchell <wmitchell at shed.org.au>
Cc: Linux user group <linux at samba.org>
I thought the standard was to use header continuation lines:
Cc: Warwick Mitchell <wmitchell at shed.org.au>,
Linux user group <linux at samba.org>
My mail client doesn't hand;e this well. (Not that that means a lot).
Network Consultant - Telecommunications Engineering
Research School of Information Sciences and Engineering
Australian National University - Ph: +61 2 61258620 M: +61 0417820641
Email: kim.holburn at anu.edu.au - PGP Public Key on request
Life is complex - It has real and imaginary parts.
Andrea Leistra (rec.arts.sf.written.Robert-jordan)
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