Re: The PPP negotiation failed, coz serial loopback was detected

Well, both PC's HAVE the same PCI modem
(Intel 536EP).

So, one isnt better than the other.

Umm yup. I'm not using XP's firewall.

I'm using something else.

And using Linux on the other PC, no.

The flatmate here, has her games on it.. etc..

You ever tried to update/format/change something on a womens PC lol. You'll
get your head bitten off.

Going thru the other PC (with XP), using Linux on this (when I use it),
isnt a prob. I can get onto the net no prob at all.

I might as well wipe KPPP and Gnome-PPP if it cant be done on Linux. Both
are just wasting space.

And just continue to go thru the other PC (XP) when using Linux.





"Moe Trin" <ibuprofin@xxxxxxxxxxxxxxxxxxxxxx> wrote in message
news:slrnf88l7f.gr6.ibuprofin@xxxxxxxxxxxxxxxxxxxx
On Thu, 28 Jun 2007, in the Usenet newsgroup alt.os.linux, in article
<f5vecf$3d8$1@xxxxxxxxxxxxxxx>, Paul wrote:

192.168.0.1 is the other PC here (I'm on an XP network). I'm 192.168.0.2
on an XP network.

I use it when the other PC connects to the net to get this PC on the net
thru the network.

And both PCs here have modems and both can dialup .

OK - that can make things a lot more complicated. NORMALLY, it's
expected that the home user would only have one box set for dialout or
other access to the world. Here, I have what's left of an ancient
386SX-16 laptop - no case, no keyboard, no display, consuming about 15
VA (about 10 Watts, and most of that is the hard drive) - acting as the
firewall and access point. It has broadband access, and has a modem for
backup. Thus, all of the systems on the LAN are pointed at this laptop
as their default gateway to the world. Now I also have yet another
modem in the print-server, and it is configured and ready to connect to
the cable modem, or dial in as needed (though both interfaces are now
unplugged to avoid possible lightning damage), BUT because it's not the
primary way out to the world, none of the other systems list it as a
gateway of any kind. If the laptop dies (it _is_ over 18 years old),
I'll simply trigger a script to change the default gateway on the LAN
hosts, and plug in the proper cables.

Before I got broadband, I had the pppd on the 386SX-16 running in
'demand' mode - any packets sent to this box for the Internet caused it
to dial out to the ISP automagically. When the link went idle for a
specified period (I used 5 minutes), it hung up the phone without user
intervention. Thus, I didn't even have to click on some icon to
access the Internet.

Problem for you - there can only be one default gateway. The word is
being used the the 'programming' sense, of "if no choice is made, the
default will be used". Think of it as "if you don't want to use A, B,
or C, then use D" _and_ "if you don't want to use A, B, or C, then use
E" - which are you going to use, D, or E? In the case of the Linux
operating system, when two routes lead to the "same" place (and "the
world" is considered one place) then use the one with the lowest
Metric (look at /sbin/route -n). If the Metric (cost) are equal,
then use the last one under the presumption that the user changed his
mind, and forgot to cancel/delete the previous choice.

Normally, setting up routing is a privileged task (requires "root"
permission) and "root" is supposed to know what root is doing. The
reason is simple: fundamental security. pppd is well aware of this
issue, and requires you to set up privileged functions if you are
going to _change_ the default route (think of a business, where some
id10t is going to use a ppp setup to _bypass_ the company firewall).
One Linux distribution (SuSE) modified the ppp daemon they were
distributing by adding a "replacedefaultroute" option. Neither of the
program authors (Paul Mackerras and James Carlson) considered the
option anything but a security problem, and no one else adopted this
"improvement".

How to get around this? I'd use the box with the better modem as a
primary. The fact that the other box is running XP and thus lacks a
lot of security functions (why does windoze need anti-virus,
anti-spyware, and if you're smart, an after market firewall app in
place of the "firewall" supplied by microsoft, while Linux doesn't need
this stuff), should also suggest using Linux as the default, but
it's your systems, and your call.

Old guy


.

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