[nos-bbs] JNOS on Debian Etch
George [Skip] VerDuin
k8rra at ameritech.net
Thu Mar 5 22:05:04 EST 2009
Darn Jay...
Jay Nugent wrote:
> Greetings Skip,
>
> On Thu, 5 Mar 2009, George [Skip] VerDuin wrote:
>
>
>> Recently I fell on to a couple details where two Linux distros act
>> differently.
>> Fedora 10 is the OS for my station and my neighbors.
>> Debian Etch is one of several distros I'm using for a project.
>>
>> The first is seen on the establishment of tun bridge. In the statement:
>> ...ifconfig tun0 192.168.1.32 pointtopoint 44.102.132.20 mtu 1500 up
>> it matters if the address carries a preceding zero. This means that
>> a) 44.102.132.20 is OK
>> b) 44.102.132.020 fails -- resulting in an IP of 44.102.132.39
>> as seen later in both "ifconfig" and "route". When it fails, the
>> session acts badly.
>>
>
> It is not failing, it is doing exactly what you told it to do. But it
> is a common mistake, so don't feel bad. Linux lets you enter dotted-quad
> IP addresses in any of several numberical forms. You *can* enter them in
> decimal, octal, hex, even binary!
>
> .20 decimal is 20 decimal
> .020 hex is 32 decimal (you seemed to get 39 for some reason ????)
>
OK - I speak hex as "0x..." not "0..."
And the # I really used was ...47 not ...20.
That's 0x2f that I recognise -- not 39 that I don't recognise.
I don't speak octal - forgot all that in 50 years, it's deprecated.
But that number is bigger than 47 -- 57 not 39 either.
And I guess I speak binary, but not here.
Anyway what you put on the table makes some sense -- but where did the
"x" go?
Since when are "0" and "0x" equivalent?
And 39?
Should I believe 2f shows up as 39 because the "f" doesn't fit (bad carry)?
So there is more to the dotted-quad format than meets the eye than a
"preceding zero".
We are not there yet...
The rule just is(?) *don't* use fixed 3-digit numbers --> *drop* the
leading zeros.
No reason -- just a rule?
I did make an even bigger boo-boo though. In re-checking out the above
I discovered that F-10 *does act the same* as Etch on this IP. I don't
know how I missed it before. It may be limited to the "pointtopoint" IP
though.
>
>
> Anyway, try entering an IP address in hex, like 0x9a434b63
>
> ifconfig eth0:99 0x9a434b63
>
> eth0:99 Link encap:Ethernet HWaddr 00:10:dc:38:fa:d9
> inet addr:154.67.75.99 Bcast:154.67.255.255 Mask:255.255.0.0
> UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
> Interrupt:16 Base address:0xe000
>
> 9a434b63 hex == 154.67.75.99
>
> Fun stuff :)
>
> Enjoy!
> --- Jay WB8TKL
So what about the equivalence of "login" and "ssh" sessions?
73
Skip
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