Telnet connect fail with IP6

HI

Anyone know why I get this with IP6? I'm running Suse 10.3.

$ telnet fe80::21a:a0ff:fe64:3ebd 4000
Trying fe80::21a:a0ff:fe64:3ebd...
telnet: connect to address fe80::21a:a0ff:fe64:3ebd: Invalid argument

Yet if I use ::1 it works fine.

$ telnet ::1
4000
Trying ::1...
Connected to ::1.
Escape character is '^]'.

Anyone have any ideas? The ip6 address above is from ifconfig output
and is definately correct.

B2003

Hello,

(E-Mail Removed) a écrit :
>
> Anyone know why I get this with IP6? I'm running Suse 10.3.
>
> $ telnet fe80::21a:a0ff:fe64:3ebd 4000
> Trying fe80::21a:a0ff:fe64:3ebd...
> telnet: connect to address fe80::21a:a0ff:fe64:3ebd: Invalid argument
>
> Yet if I use ::1 it works fine.

A link local address (fe80::something) is not unique and may be
reachable on any directly connected link, so you need to indicate the
interface through which you want to reach that address. For instance if
it's eth0 :

$ telnet fe80::21a:a0ff:fe64:3ebd%eth0 4000

Pascal Hambourg a écrit :
>
> A link local address (fe80::something) is not unique and may be
> reachable on any directly connected link, so you need to indicate the
> interface through which you want to reach that address. For instance if
> it's eth0 :
>
> $ telnet fe80::21a:a0ff:fe64:3ebd%eth0 4000

Note that if the address belongs to an interface of the host running the
telnet client and thus is a local address, then the interface through
which you reach that address is the loopback interface lo, *not* the
interface on which the address is configured.

On Jul 10, 4:32 pm, Pascal Hambourg <boite-a-s...@plouf.fr.eu.org>
wrote:
> Pascal Hambourg a écrit :
>
>
>
> > A link local address (fe80::something) is not unique and may be
> > reachable on any directly connected link, so you need to indicate the
> > interface through which you want to reach that address. For instance if
> > it's eth0 :
>
> > $ telnet fe80::21a:a0ff:fe64:3ebd%eth0 4000
>
> Note that if the address belongs to an interface of the host running the
> telnet client and thus is a local address, then the interface through
> which you reach that address is the loopback interface lo, *not* the
> interface on which the address is configured.

I'm beginning to see why people don't want to bother with IP6. There
seems to be a lot of needless complexity in many aspects of it.

Thanks for your help though , works fine now.

B2003

(E-Mail Removed) wrote:
> HI
>
> Anyone know why I get this with IP6? I'm running Suse 10.3.
>
> $ telnet fe80::21a:a0ff:fe64:3ebd 4000
> Trying fe80::21a:a0ff:fe64:3ebd...
> telnet: connect to address fe80::21a:a0ff:fe64:3ebd: Invalid argument

Not sure.. but are you allowed to connect to the link local
address?? Do you have a Global address you can use instead?

Not saying that is the issue....

>
> Yet if I use ::1 it works fine.
>
> $ telnet ::1
> 4000
> Trying ::1...
> Connected to ::1.
> Escape character is '^]'.
>
> Anyone have any ideas? The ip6 address above is from ifconfig output
> and is definately correct.

But it is the link local addy.

(E-Mail Removed) wrote:
.....
>
> I'm beginning to see why people don't want to bother with IP6. There
> seems to be a lot of needless complexity in many aspects of it.

IPv6 started out ok, then many people with NO EXPERIENCE and lots
of AGENDAS took it over. It doesn't deserve to live, but we
don't have much choice at this point. Better get used to it.

In general, it's not hideous, but like it's predecessor, it has
some major short comings and shows the "design by committee"
issues.

VERY SLOW adoption. Lots (and I mean LOTS) of protocols are
NOT adapted for IPv6 and will take some work. Slow deployment
of the Internet and lack of knowledge by the Telco's and ISP's
aren't helping. Also, EVERYONE is looking to capitalize
on the technology. Expect LOTS of rip offs as this pig goes
out.

And the world will pay... because they don't know any better.

(E-Mail Removed) a écrit :
>>
>>>$ telnet fe80::21a:a0ff:fe64:3ebd%eth0 4000
>
> I'm beginning to see why people don't want to bother with IP6. There
> seems to be a lot of needless complexity in many aspects of it.

Maybe I should have mentionned that the average user should not need to
bother with or even know about IPv6 link local addresses, so this is
mostly hidden complexity. They are not supposed to be used by "common"
applications (i.e. not IPv6-specific networking tools).

If you want to communicate in IPv6 with the local host, use the loopback
address ::1. If you want to communicate in IPv6 with remote hosts, setup
and use global addresses (~public) or unique local addresses (~private)
as you would do in IPv4.

On Jul 11, 8:49 am, Pascal Hambourg <boite-a-s...@plouf.fr.eu.org>
wrote:
> If you want to communicate in IPv6 with the local host, use the loopback
> address ::1. If you want to communicate in IPv6 with remote hosts, setup
> and use global addresses (~public) or unique local addresses (~private)
> as you would do in IPv4.

Yes , but the point is I shouldn't have to tell a client which
physical interface to use to connect even to an internal address. That
should be taken care of in the kernel routing system as with IP4. If
someone is setting up an test system internally on a machine using
various addresses this will be a total PITA.

B2003

(E-Mail Removed) a écrit :
>
> Yes , but the point is I shouldn't have to tell a client which
> physical interface to use to connect even to an internal address. That
> should be taken care of in the kernel routing system as with IP4.

I suspect that this is not specific to IPv6 but to its implementation in
Linux, which checks the destination address scope before checking
whether it is internal or not.

On the other hand, ping6 to an internal link-local address on Windows
2000 with IPv6 extension pack does not require you specify the output
interface.

> If
> someone is setting up an test system internally on a machine using
> various addresses this will be a total PITA.

As I said, set up global or unique local addresses on your hosts for any
purpose. Using link-local addresses is a bit like using MAC addresses.