Re: Re^2: Telnet does not work in 2.0.10 ??

madams (madams@fgi.net)
Fri, 2 Aug 1996 18:47:27 -0500 (CDT)


On Fri, 2 Aug 1996 unix-l@inacom.com wrote:

> Michael Slater wrote:
> > When using Linux kernel version 2.10, Telnet seems to be broken.
> > I cant even telnet to localhost. It says trying 127.0.0.1 and just sits
> > there and does nothing. Telneting from another Linux Box into the same
> > machine does not work either. But if i telnet in from a Windows machine
> over
> > the ethernet, it works just fine. Anybody have a clue whats wrong ?
>
> David Dight wrote:
> >Works fine on our system. We're running 2.0.10. We can telnet to and from
> >the system with no problems. Check your net setup.
>
> I have Caldera setup at home and noticed that the routing table did not
> have a route for the 127.0.0.0 network. I checked the network setup files
> and found that when it called the route add command,it was calling it with
> "route add -net 127.0.0.1", and it should be using "route add -net
> 127.0.0.0".
> I also noticed that (since I had upgraded to kerneld and kernel loadable
> modules, I did not have an alias for the loop-back device to the dummy.o
> so whenever a call was made to the lo device, it was going to the bit
> bucket.
>
> Check these things -- might be how Caldera and their route binary works.
>
> Dan

The below is taken from the Changes file in /usr/src/linux/Documentation:

Upgrade notes
*************

Network errors with recent kernels
==================================

Many default network scripts are set up to add a route to the
localhost at 127.0.0.1 at startup. However, they do this incorrectly.
To fix the error, which is now spotted by the kernel (causing many
daemons to quit working), look for a line like `route add -net
127.0.0.1' in your network configuration files and change it to `route
add -net 127.0.0.0'.

This error is present in all Red Hat distributions (and derivative
distributions like Caldera). If you're running one of these, edit
/etc/sysconfig/network-scripts/ifup-lo, changing the line `route add
-net $(IPADDR)' to `route add -net 127.0.0.0' and you should be fine.