How to start setting up LAN

I have two computers I would like to network with each other.
Each has an ethernet card and one of the cards on each provides
internet access through the switch and a wireless bridge. The
other cards are connected with a crossover cable.

How should I proceed? Many experiments I tried have either
produced nothing or disaster, so I know I'm missing some basic
understanding.

I have assigned the address 192.168.1.99 to the local ethernet
card, and when I ping it answers, but I haven't succeeded in
getting any other of the local addresses I assigned on either
computer to respond. Is it necessary to configure one of them
as a router?

When I assign an address in /etc/hosts, should I be using the
same domain name as on the internet access side of things?

On Fri, 24 Sep 2004 21:27:37 -0700, Bert Rubash <(E-Mail Removed)> wrote:
> I have two computers I would like to network with each other.
> Each has an ethernet card and one of the cards on each provides
> internet access through the switch and a wireless bridge. The
> other cards are connected with a crossover cable.
>
> How should I proceed? Many experiments I tried have either
> produced nothing or disaster, so I know I'm missing some basic
> understanding.
>
> I have assigned the address 192.168.1.99 to the local ethernet
> card, and when I ping it answers, but I haven't succeeded in
> getting any other of the local addresses I assigned on either
> computer to respond. Is it necessary to configure one of them
> as a router?

We cannot tell from the data provided if you have a network, hardware, or
firewall problem, or how you are connected to internet (public IPs, or
NAT router). First check boot messages or /var/log/messages to see
if there is any problem enabling the hardware.

To check potential routing problems, it helps to post the output of
/sbin/ifconfig and "/sbin/route -n". If you want to disguise any IPs, at
least include the part to the right for the number of zeros in the
netmask. You should not have the same network/netmask pair on more than
one interface (except special cases per Adv-Routing HOWTO). For your
crossover interface, you should not have any gateway (a gateway should
typically only lead to internet). If your broadband router uses
192.168.1.x IPs on its LAN, it is best to use a different IP range on your
crossover network, although, you could used such IPs for crossover if they
have netmask 255.255.255.255 and a -host route to IP of other machine.

If running a firewall (enabled by default on some systems) it may need to
be modified or refreshed when connecting another interface.

> When I assign an address in /etc/hosts, should I be using the
> same domain name as on the internet access side of things?

Local private IPs should usually have names that cannot possibly be
confused with registered names (unless you own the name), so avoid using 2
or 3 letters after the last dot. And just plain "local" is now a reserved
name for multicast, so do not use that for a domain. Note that names for
local IPs do not necessarily need to match hostnames, but something in
/etc/hosts should at least point a box's own name at an IP on it.

Some possibly relevant lines from /var/log/messages:

Sep 25 08:12:53 tux e100: Intel(R) PRO/100 Network Driver, 3.0.17
Sep 25 08:12:53 tux e100: Copyright(c) 1999-2004 Intel Corporation
Sep 25 08:12:53 tux e100: eth0: e100_probe: addr 0xd5000000, irq 10, MAC
addr 00:90:27:C7:89:49
Sep 25 08:12:53 tux natsemi dp8381x driver, version 1.07+LK1.0.17, Sep 27,
2002
....
Sep 25 08:12:53 tux 2.4.x kernel port by Jeff Garzik, Tjeerd Mulder
Sep 25 08:12:53 tux eth1: NatSemi DP8381[56] at 0xe09d0000,
00:09:5b:e1:56:59, IRQ 12.
Sep 25 08:12:54 tux eth1: link up.
Sep 25 08:12:54 tux eth1: Setting full-duplex based on negotiated link
capability.
Sep 25 08:12:54 tux e100: eth0: e100_watchdog: link up, 100Mbps, full-duplex
Sep 25 08:12:54 tux ohci_hcd: 2004 Feb 02 USB 1.1 'Open' Host Controller
(OHCI) Driver (PCI)
Sep 25 08:12:54 tux ohci_hcd: block sizes: ed 64 td 64
Sep 25 08:12:56 tux lp0: using parport0 (polling).
Sep 25 08:12:58 tux dnsmasq[6797]: started, version 2.9 cachesize 150
Sep 25 08:12:58 tux dnsmasq[6797]: read /etc/hosts - 12 addresses
Sep 25 08:12:58 tux dnsmasq[6797]: reading /etc/resolv.conf
Sep 25 08:12:58 tux dnsmasq[6797]: using nameserver 216.57.207.18#53
Sep 25 08:12:58 tux dnsmasq[6797]: using nameserver 216.57.214.17#53

ifconfig:

eth0 Link encap:Ethernet HWaddr 00:90:27:C7:89:49
inet addr:216.57.214.59 Bcast:216.57.214.63 Mask:255.255.255.224
UP BROADCAST NOTRAILERS RUNNING MULTICAST MTU:1500 Metric:1
RX packets:250 errors:0 dropped:0 overruns:0 frame:0
TX packets:155 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:101973 (99.5 Kb) TX bytes:17306 (16.9 Kb)

eth1 Link encap:Ethernet HWaddr 00:09:5B:E1:56:59
inet addr:192.168.1.99 Bcast:192.168.1.255 Mask:255.255.255.0
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:0 errors:0 dropped:0 overruns:0 frame:0
TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:0 (0.0 b) TX bytes:0 (0.0 b)
Interrupt:12

lo Link encap:Local Loopback
inet addr:127.0.0.1 Mask:255.0.0.0
UP LOOPBACK RUNNING MTU:16436 Metric:1
RX packets:10 errors:0 dropped:0 overruns:0 frame:0
TX packets:10 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:0
RX bytes:500 (500.0 b) TX bytes:500 (500.0 b)

route -n:

Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use
Iface
216.57.214.32 0.0.0.0 255.255.255.224 U 0 0 0 eth0
192.168.1.0 0.0.0.0 255.255.255.0 U 0 0 0 eth1
127.0.0.0 127.0.0.1 255.0.0.0 UG 0 0 0 lo
0.0.0.0 216.57.214.33 0.0.0.0 UG 0 0 0 eth0

Internet access is to an antenna on a nearby fish processing plant.
I don't have details: I was sent the wireless bridge in the mail;
I plugged it into the ethernet card and it worked. I originaly
accessed my provider (a different company than the wireless service
provider) through a phone line.

David Efflandt wrote:

> ... Note that names for
> local IPs do not necessarily need to match hostnames, but something in
> /etc/hosts should at least point a box's own name at an IP on it.

One of the problems I face is making abstractions concrete and catching
on the meaning of new terms. I don't understand what it means to
"point a box's own name at an IP on it". Is 'box' the referent of 'it'?
Does IP, here, mean Internet Protocol address?

I set the addresses of local hosts to the same IP addresses as the
local network ethernet cards on each computer, and ping returns echoes
from both hosts from either computer. The card IP addresses are different
from each other.

I also managed to get the lisa daemon running on one of the computers
and I get two empty file folders when I use lan:/ in Konqueror.

Am I going in the right direction, do I really have working hosts, or
just alternate names for the ethernet cards?

What's next? Advice anyone?

On Sat, 25 Sep 2004 12:27:47 -0700, Bert Rubash <(E-Mail Removed)> wrote:
> David Efflandt wrote:
>
>> ... Note that names for
>> local IPs do not necessarily need to match hostnames, but something in
>> /etc/hosts should at least point a box's own name at an IP on it.
>
> One of the problems I face is making abstractions concrete and catching
> on the meaning of new terms. I don't understand what it means to
> "point a box's own name at an IP on it". Is 'box' the referent of 'it'?
> Does IP, here, mean Internet Protocol address?

A computer (box) needs to be able to find an Internet Protocol address
(IP) on itself for its own hostname, for many networking things to work.
For example sendmail may hang for awhile during boot if it cannot resolve
its hostname to a local IP.

The one post showing no TX/RX traffic appeared like it was not working,
even though it should have been from log messages. But if they are now
able to ping each other, it looks like you are on your way.

--
David Efflandt - All spam ignored http://www.de-srv.com/