[clug] how to use traceroute

[Eyal Lebedinsky]

On 06/25/14 10:09, Bob Edwards wrote:
> On 25/06/14 09:31, Eyal Lebedinsky wrote:
>> I used it before to see what is going on with routing. However, there is
>> something going
>> on with iinet recently, and a download test from ftp.iinet.net.au ran at
>> around 50k/s for
>> a line sync of 6-7Mb/s.
>>
>> I did a 'traceroute ftp.iinet.net.au' and it went all the way to 30
>> hops. I added '-m 255'
>> and it still went all the way. Looks like some kind of loop between
>> 203.0.178.32 (ftp.iinet...)
>> and 203.215.4.197 (no DNS). It is still doing this now.
>>
>> I find this unusual but maybe I do not understand how it works and why
>> this is acceptable.
>>
>> Can anyone explain why this is so and is this normal?
>>
>> TIA
>>
>> --
>> Eyal Lebedinsky (eyal at eyal.emu.id.au)
>
> traceroute is less useful these days as the low TTLs can be detected and
> the resulting ICMP messages not returned by many routers.
>
> You may fare a bit better with tcptraceroute and using the default port
> 80 (everyone lets tcp/80 through...). But the short TTLs can still be
> detected by the routers and the ICMP layer may not respond.
>
> Cheers,
>
> Bob Edwards.

Thanks Bob,

tcptraceroute works and gives the expected results. Live and learn.

cheers

-- 
Eyal Lebedinsky (eyal at eyal.emu.id.au)