[PLUG] it gets weirder - was Linux 7.2 printer problem solved
J.A. Henshaw
jeff at jhenshaw.com
Thu Mar 21 17:42:03 UTC 2002
Michael Rasmussen wrote:
> I got curious about why the configuration of 192.168.200.081 doesn't work.
> Poked around on the machine for a bit and found that `ifconfig
> 192.168.0.001` works as does `ifconfig 192.168.0.071`
>
> Then a bit of shell:
>
> for i in 6 7 8 9
> do
> for j in 0 1 2 3 4 5 6 7 8 9
> do
> ifconfig eth0 down
> echo trying 0$i$j >> conflog
> ifconfig eth0 192.168.200.0$i$j >>conflog 2>&1
> echo trying $i$j >> conflog
> ifconfig eth0 192.168.200.$i$j >> conflog 2>&1
> done
> done
>
> And the results show an error whenever a digit larger than 7 is in the
> specified address:
>
> trying 067
> trying 67
> trying 068
> 192.168.200.068: Unknown host
> ifconfig: '--help' gives usage information.
> ...
> trying 077
> trying 77
> trying 078
> 192.168.200.078: Unknown host
> ifconfig: `--help' gives usage information.
> trying 78
>
> So Robert, the real answer to your question is:
>
> an IP address ending in .081 is invalid - because the leading 0 tells the
> software to interpret the number in octal. In octal only digits 0-7 are
> valid. For that matter and address of say 192.168.081.001 would also be
> invalid. Because the 3rd octet is not a valid octal number.
>
> You could also try something like `ifconfig eth0 192.168.0x081.1` which
> would result in an address of 192.168.129.1.
>
> Thanks for the interesting problem.
>
> --
> Michael Rasmussen - Network Engineer, Columbia Management
> voice: 971-925-6723 cell: 503-807-1447 rasmussenm at columbiafunds.com
> <mailto:rasmussenm at columbiafunds.com> http://www.columbiafunds.com
>
Michael, Thanks for the interesting analysis as well!
Give that man a raise!!
I hope YOU didn't sign any oppressive employment contracts
re open source.... :)
jH
>
>
--
Democracy is when two wolves and a sheep vote on what they
will have for lunch.
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