Autoipd fails to give ip address to eth0:0

Hi,

I have a problem under Fedora Core. Autoipd (the part of Howl which
gives local link addresses supporting Zeroconfig) will give an ip
address to eth0 correctly, but the following does nothing, though it
returns without an error.

autipd -i eth0:0

Am I doing something wrong? Any help would be really appreciated.

Cheers,

-R.

(E-Mail Removed) wrote:
> Hi,
>
> I have a problem under Fedora Core. Autoipd (the part of Howl which
> gives local link addresses supporting Zeroconfig) will give an ip
> address to eth0 correctly, but the following does nothing, though it
> returns without an error.
>
> autipd -i eth0:0
>
> Am I doing something wrong? Any help would be really appreciated.

What are you thinking to achieve?

The Zeroconf addresses are in the same subnet (169.254.0.0/16),
and there is no sense in giving two of them to the same intereface.

--

Tauno Voipio
tauno voipio (at) iki fi

Yeah, I'm aware of the ip range... and I have to disagree, there are
very good reasons to do this. In this case, I have two services running
on the same system which need to each bind to their own interface or
they cannot send and receive traffic on the same port.

But back to my question, do you know why autoipd will not assign to a
virtual interface?

-R.

(E-Mail Removed) wrote:
> Yeah, I'm aware of the ip range... and I have to disagree, there are
> very good reasons to do this. In this case, I have two services running
> on the same system which need to each bind to their own interface or
> they cannot send and receive traffic on the same port.

You cannot do it - there are no separate ports for the
different IP addresses present on a host. The IP alias
on an interface does not create additional parallel ports.

Besides, having two interfaces in the same subnet is
not a good idea in the general case. It makes simple
routing impossible. There are special cases, e.g.
load balancing, but a pair of aliased interfaces
on a common NIC does not apply here.

> But back to my question, do you know why autoipd will not assign to a
> virtual interface?

It is against the design philosophy of the zero configuration
system. Please read the documents at <http://www.zeroconf.org/>.

--

Tauno Voipio
tauno voipio (at) iki fi

Really... Odd, it works great statically or with dhcp. We have a
software version of a device that was previously hardware based running
beside the application that uses it. We have eth0 and eth0:0 configured
on different ips with the two processes using them to talk to each
other and the network on the same port. We are using a virtual
interface to save us the unnecessary cost of a second nic. I appreciate
your reply and opinions, but I do not think you understand my question.
There is no problem with my network configuration. It absolutely and
positively works for all cases except local link addressing.


It looks like there is a problem with virtual interfaces and autoipd.
If you can help with this part, please let me know.

Kind regards,

-R.

(E-Mail Removed) wrote:
> Really... Odd, it works great statically or with dhcp. We have a
> software version of a device that was previously hardware based running
> beside the application that uses it. We have eth0 and eth0:0 configured
> on different ips with the two processes using them to talk to each
> other and the network on the same port. We are using a virtual
> interface to save us the unnecessary cost of a second nic. I appreciate
> your reply and opinions, but I do not think you understand my question.
> There is no problem with my network configuration. It absolutely and
> positively works for all cases except local link addressing.
>
>
> It looks like there is a problem with virtual interfaces and autoipd.
> If you can help with this part, please let me know.

Is the service e.g. Apache?

Did you read the zeroconf documentation?

--

Tauno Voipio
tauno voipio (at) iki fi

No it's not, and yes I have. Do you actually have any knowledge
regarding autoipd and virtual interfaces?

Hi,

I'm replying to my own post with a work around in case someone else out
there has a similar problem.

If you statically bind eth0:0 in the 169.254.0.0/16 space and then
autoipd eth0, you will get the desired behavior. It is admittedly not a
good solution, but it will make things work.

Cheers,

-R.

(E-Mail Removed) wrote:
> Hi,
>
> I'm replying to my own post with a work around in case someone else out
> there has a similar problem.
>
> If you statically bind eth0:0 in the 169.254.0.0/16 space and then
> autoipd eth0, you will get the desired behavior. It is admittedly not a
> good solution, but it will make things work.

It seems that you did not understand the zeroconf documentation
you said you did read ...

Please re-read the conditions for using the link-local address range.

--

Tauno Voipio
tauno voipio (at) iki fi