Department of Mathematics, Statistics
and Computer Science
Wim Ruitenburg's MSCS 206 linux learning 971017
- We have two linux boxes in the room, both on the same local Net. One
is guest.mscs.mu.edu with IP address 134.48.4.79, the new machine. The other
is warrior.mscs.mu.edu with IP address 134.48.4.141. We let warrior ping guest
with the command
ping guest
and let guest ping warrior with the command
ping warrior
We don't have to type the full addresses ping guest.mscs.mu.edu or
ping warrior.mscs.mu.edu, because our domain name server knows how to
read the abbreviated versions and determine the proper IP addresses of the
machines. These proper IP addresses are then used by the machines to actually
perform the pinging. We test the connections by occasionally unplugging one of
the machines off the Net.
- We wish to make the new linux box guest into the student machine
warrior, and temporarily turn the old warrior into guest. To be on the safe
side, we unplug one of the two machines from the web, and run
netconfig
on both machines. It suffices to describe the case of converting guest into
warrior. Netconfig asks us for our future machine name, warrior, asks
for our extension, mscs.mu.edu, and asks for our future IP address,
134.48.4.141. This IP address really stands for the bit string
10000110.00110000.00000100.10001101
As an aside, one could have found the IP of warrior from the domain name server
beforehand, if we had typed nslookup warrior.
Next comes the netmask, the fragment of our 32 bit address that belongs to the
local group address. Last time we mentioned that the mask's bit pattern happens
to be
11111111.11111111.11111110.00000000
In decimal form this reads 255.255.254.0, our netmask.
The following number is our gateway, the IP address of the device that is
designated to facilitate communication between our local group and the outside
world (in practice all machines with an IP address that differs in a netmask
level bit position). It happens to be 134.48.4.100. As an aside, we could have
found this out in advance by tracing the route that internet packets travel
from the machine (when it was still guest) to any nearby machine outside our
local group, because such a path would first have to cross this gateway. So the
gateway is found by, for example, executing traceroute 134.48.1.32, the
IP address of a machine we heard about last time (in fact, it is the IP address
of our domain name server). This brings us to the final question. Do we have a
domain name server? The answer is yes, and the number is 134.48.1.32. Done.
Lazy as we are, we restart the machine by typing the command
shutdown -r now
Now the PC acts as warrior. In the meantime the other machine is turned from
warrior into guest.
- We want to end with installing an X windows configuration. Information
on configuration of lots of things is stored in the subdirectory
/usr/doc/faq/howto
We go into this directory, where we find the file XFree86-HOWTO.gz. Type
less XFree86-HOWTO.gz
From reading this file we can learn a lot about X installation. One thing we
learn is that we can run the installation program XF86Setup. Run
XF86Setup
First, using the <enter> and tab keys we set our PS/2 mouse up in
3-button mode, and do apply. The mouse works. Warning: During this phase
we are not allowed to move the mouse or press its buttons! Second, we select
our video card which happens to be `oak generic' (this sort of information can
be found beforehand by typing SuperProbe). Third, we have to select the
monitor setting. Our monitor can handle 1024x768, but it is sometimes tricky
to install and finetune high resolution X. So instead we select the safe
and secure VGA setting at 640x480 (essentially always works). Proper exiting
automatically finishes the installation of the file /etc/XF86Config. Then type
startx
A low-resolution version of X appears on the screen.
Finetuning to a higher resolution will be done later. For those who are
curious, get your manufacturer's monitor manual, go to the directory
/usr/doc/faq/howto/mini, and type
less Modeline.gz
This is only a start.
Last updated: November 1998
Comments & suggestions:
wimr@mscs.mu.edu