Best of Technical Support
Net Radio vs. Downloads
An engineer wants to listen to music over the Internet using
a 1MB, two-way DSL connection. Another engineer complains during this
session that his downloads are very slow. Now these two engineers
want the technician to monitor the network and show the percentage of
use of the music and downloads on this Ethernet connection.
The technician has Ethereal installed and resolves most problems with
this tool, but he finds it a poor performance monitoring tool. I,
being the technician, want to know if I am not using Ethereal to its full
capability in monitoring the network. Or, is there another tool I can
use to perform this function?
—
George Van Tuyl
gvtlinux@xmission.com
A product called the Multi Router Traffic Grapher,
www.mrtg.org, when configured properly and in conjunction
with your iptables and other network settings, could provide the data
analysis you need.
—
Felipe Barousse Boué
fbarousse@piensa.com
If you want to use traffic control on your Linux
router to balance the need for responsive interactive
connections with the demand for fast downloads,
check out the “Ultimate Traffic Conditioner” section
of lartc.org.
—
Don Marti
dmarti@ssc.com
Changing Desktop Environments
How do you change the default window manager on Red
Hat? Let me clarify. I log in with text, and when I
type startx, it starts GNOME, but I'd like to use KDE.
—
Weoh
errff@hotmail.com
You can change the content of /etc/sysconfig/desktop
from DESKTOP="GNOME" to
DESKTOP="KDE" or
DESKTOP="WINDOWMAKER", and X will start the
corresponding window manager. The file that controls
which window manager it starts is /etc/X11/xinit; take
a look at it.
—
Felipe Barousse Boué
fbarousse@piensa.com
Hardware Specs for Laptop?
I am attempting to load Red Hat 7.3 on a Sony VAIO notebook,
model no. PCG-GRT 250P. I need to know what horizontal and
vertical sync values must be entered for the LCD screen.
—
Noel Haynes
atannah@hotmail.com
From what I have found, your VAIO
should have a horizontal range of 27–115 and a vertical range of
50–160. My last suggestion would be
to install, say, Fedora Core 1 instead of Red Hat 7.3,
which has newer X versions.
I do not own a VAIO, but in looking around I
found this page that may be a good reference for
you: www.prongs.org/linux/sony/sony.html.
The page www.linux-on-laptops.com links to
configurations for many laptop models.
—
Felipe Barousse Boué
fbarousse@piensa.com
Displaying an Image in an X Application
I'm working on digital image processing on Linux. I have read
a .bmp image successfully. Now I have to display the image using X11. I have
used XCreateImage() and XPutImage(), but the figure is not being
displayed. I feel the problem is with the arguments I pass to these
functions. How do I do it?
—
shilpa.s
s_shilpa_15@yahoo.com
Try using the sample code from this X tutorial:
www.xmission.com/~georgeps/Xlib/Xlib_JPEG_tutorial.html.
—
Christopher Wingert
cwingert@qualcomm.com
Encrypted Cross-Platform Remote Desktop?
Does Linux come packaged with something similar to Windows 2000 Advanced
Server's Terminal Services? I have a Windows XP workstation that needs
to be configured to have remote access to a Linux server's applications.
The connection would be over the Internet—a VPN, perhaps?
—
William
billhcmp405@hotmail.com
Yes, there is a cross-platform remote desktop
solution. VNC for Linux and Microsoft Windows is
available under the GNU GPL from RealVNC (realvnc.com), and
there may also be VNC packages available for your
Linux distribution. If your distribution supplies
a VNC package, you should probably use it so that
the software will be easier to update if necessary.
See the RealVNC FAQ for how to encrypt a VNC
session using SSH.
—
Don Marti
dmarti@ssc.com
Mysterious Freezing Hardware
I recently purchased a new computer for the boss,
an AMD 2500+ with a Biostar M7NCG motherboard,
1.5GB of RAM and two IDE hard drives. After a
couple of months, it began freezing once or twice
a day. No single application is to be blamed. I've
tried replacing hardware and even went so far as to
put the hard drives in a totally different computer,
which did not resolve the issue. What are the best
ways of troubleshooting such a problem?
—
Leroy Powell
lspow80@yahoo.com
First, this looks like a hardware problem, not necessarily Linux-related
though. Without specifics, it is hard to guess what is going on. Let's
suppose you have Linux in it, then when you say “freezing”, is it the
whole machine that freezes or only the graphical user interface? Those
are quite different situations. I'd first look at the system logs. If
it is the whole machine locking, probably switch memory banks,
take some memory out and try the system. If the GUI is what freezes,
I would inspect the video card. Also, check for the latest drivers, or
a newer Linux distribution may solve your problem.
—
Felipe Barousse Boué
fbarousse@piensa.com
I hate to say it, but in a business, a PC that's
out of warranty and has an intermittent problem is
worth less than the time required to diagnose it.
Assuming your boss pays you a fair wage, he's better
off buying a new box with a longer warranty. Put this
time-sucker out on the sidewalk.
—
Don Marti
dmarti@ssc.com
Binding a Key to Send a Signal
What should I do to generate a SIGHUP signal when I
press Ctrl-K?
—
Narayanan Iyer
narayanan.iyer@wipro.com
You can use the bash bind command to assign certain
behavior to key sequences. The .inputrc file is
related as well. Do a help bind from within bash
or see the “shell builtin commands” section of the
bash man page for further information. Take a look at
en.tldp.org/HOWTO/Keyboard-and-Console-HOWTO.html
for more information, or go to
www.linuxgazette.com/issue55/henderson.html
for a hot key creation tutorial.
—
Felipe Barousse Boué
fbarousse@piensa.com