Re: whats wrong with my IP address?

Zach Brown (zab@grumblesmurf.net)
Tue, 19 Nov 1996 17:50:48 -0800 (PST)


On Tue, 19 Nov 1996, Dave Wreski wrote:
>
> On Tue, 19 Nov 1996, D. Chiodo wrote:
>
> >
> > Exactly what problems are you having?
>
> Oh boy, all kinds of problems :)
>
> My 'network' consists of my ppp account to my ISP, another linux box, and
> a sparc 2. I have no problem assigning '192.107.200.0' as a network on my
> sparc, but I can't get it to work like it used to on my linux boxes with
> redhat 4.0.
>
> There seems to be something more fundamentally wrong here. Even something
> as simple as 'route add -net 127.0.0.0' gives me 'SIOCADDRT: Network is
> unreachable'.

how about: "route add -net 127.0.0.0 netmask 255.0.0.0 lo" ? works for
me. what is the current contents of your routing table? you are bringing
up lo before doing the route command, right?

> lo Link encap:Local Loopback
> inet addr:127.0.0.1 Bcast:127.255.255.255 Mask:255.0.0.0
> UP BROADCAST LOOPBACK RUNNING MTU:3584 Metric:1
> RX packets:2 errors:0 dropped:0 overruns:0
> TX packets:2 errors:0 dropped:0 overruns:0

looks fine

> > You can't just pull an individual IP address out of the air and expect it
> > to work, even if your network isnt connected to the Internet.
>
> Why is this?

by the 'not connected to the internet' bit he meant that your
host has to have the right netmask for the network and has to
have an ip address that the network admin agrees with :).

but in this case, because ip addresses have to be globally unique. what if
you actually want to send data to BOSS.OPOY.FI (192.107.200.22).. or any
of the other hosts they may have on that /24. How will you know you want
to go to your local net rather than the good old Oulu Telephone Company?
:)

there is a class a (/8) that is available just for this purpose. any
address within 10.x.x.x is specifically not globally assigned and is
designed for private networks. use that instead of 192.107.200.x. its
also a heck of a lot easier to remember :)

> I _am_ the network admin :) Admittedly, I don't seem to be a very good one
> :)
>

it takes time.. read alot of kernel source and rfcs :)

> Thanks,
> Dave

-- zach

> echo '16i[q]sa[ln0=aln100%Pln100/snlbx]sb20293A2058554E494Csnlbxq'|dc

767378858832584132

er.. am i missing something? :)