Re: Problems configuring /etc/network/interfaces
Petre, yes, my /etc/resolv.conf file is set up correctly. Thanks.
Lars,
> Charles Bray wrote:
>
> > Right now, my /etc/network/interfaces file includes the following
> lines
> > (excluding comments):
> >
> > auto lo
> > iface lo inet loopback
> >
> > My understanding is that the "auto lo" line is supposed to activate
> the
> > loopback interface at boot time. But evidently it doesn't. After I
>
> > boot and log in as root, if I ping the localhost at 127.0.0.1, I get
> the
> > error message:
> >
> > neighbor table overflow
> >
> > At this point, the routing table (route -n command) doesn't list the
>
> > loopback interface, and I must manually activate and add it with the
>
> > lines:
> >
> > ifconfig lo 127.0.0.1
> > route add 127.0.0.1 lo
>
> The route looks wrong to me. Something like
>
> route add -net 127.0.0.0 netmask 255.0.0.0 lo
>
> should be what you need..
So the lo device will take all traffic on the entire 127.0.0.0 network,
not just at 127.0.0.1. Is this preferred?
> Instead of the two command you might want to try running
>
> ifup lo
I can't tell that this command does anything, but the "route add
-net.... " line works fine, although it doesn't seem to be needed (see
below).
> > Strangely (to me), if I comment out the "auto lo" line in
> > /etc/network/interfaces and reboot, I can then successfully ping the
>
> > loopback address, indicating that the interface has been
> automatically
> > activated.
So, as of now, I've commented out the "auto lo" line to avoid the
above-described "neighbor table overflow" error, and, although the
loopback interface isn't listed in the routing table, everything works
just fine. I can ping localhost or 127.0.0.x with no problem. I wish I
understood, but I guess I don't have to right now.
> > After successfully connecting to my ISP via serial modem (and after
> > manually adding the loopback interface), the routing table is as
> > follows:
> >
> > Destination Gateway Genmask Flags Metric Ref Use
> Iface
> > 286.115.220.139 0.0.0.0 255.255.255.255 UH 0 0 0
> ppp0
> ---^ Something is definitely very very wrong here. Each field of the
> ip
> address should be in the interval 0..255, 286 just cannot happen...
Of course, you're right. I'm sorry. I tried to be very careful not to
make any mistakes, but the 8 in 286 was actually one of those zeros with
a diagonal line through it, and it looked like an 8 to my weary eyes.
Since my Linux computer isn't ready yet, I'm posting from my wife's
Windows machine.
> > 127.0.0.1 0.0.0.0 255.255.255.255 UH 0 0 0 lo
> > 192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0
> eth0
> > 0.0.0.0 192.168.1.1 0.0.0.0 UG 0 0 0
> eth0
> >
> > I can ping 286.115.220.139 as well as my machine's local network IP
> > address at 192.168.1.1, but I can't ping my ISP's DNS servers or
> > anywhere else on the internet.
>
> If you can ping that illegal address something is completely utterly
> wrong.
You make me laugh. :)
> Did you copy the info by hand and make a typo ?
< : )
> Your routing table looks very weird to me. Lets have a look...
> First of you need the loopback route:
>
> 127.0.0.0 0.0.0.0 255.0.0.0 U 0 0
> 0
> lo
>
> If its not present you should run
> route add -net 127.0.0.0 netmask 255.0.0.0 lo
Again, this doesn't seem to be necessary, but even when I do run this
command, it's not permanent. After reboot, it's gone. How can I fix
this?
> Your box is capable of finding itself without a route
I'm not sure I understand this.
> so the strange 286.... route should go. Experiment with "route del" to
> get rid of it.
The "286" route was designated automatically when I dialed into my ISP.
It's the ISP's PPP server address.
> When looking for other addresses you need to first of all be able to
> find your gateway.
.........
Please read my reply to Michael Heldebrandt regarding the gateway
problem. Thanks for all your advice and time. I deeply appreciate your
help.
Charles
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