2004.12_Charly's Column-Configuring Your Headless Server for an Lcd Device.pdf

Charly’s column

SYSADMIN

Show Me!

Every rack-mounted server doesn’t need its own dedicated monitor. But if you

decide to go headless, it helps to fit the server with an LCD device that displays

real-time information on critical events. LCDproc is the tool you need to con-

trol the display. BY CHARLY KÜHNAST

without input and output devices.

In most cases, this is fine for the

administrator; after all, you can use SSH,

serial consoles, and syslog forwarding.

But it can still make sense to fit the

server with a small LCD device. An LCD

at least gives the server a chance to alert

you to really important events. LCDproc

[1] is the software you need to control

the display.

LCDproc Version 0.4.5 supports a wide

range of displays for both the serial port

and USB. The LCDproc download is a

350 KByte tar archive. Typing

gant approach. You can type ./configure

--help to list your options. My display

was built by Crystalfontz [2]. LCDproc

even has a curses driver for it. That

may sound useless, but it does

make sense for people like me, who

develop or test their LCDproc clients

on a computer that is not fitted with

an LCD. Setting up the driver is quite

simple:

or later, additionally need the fol-

lowing two lines:

NewFirmware=yes

Speed=19200

Now let’s launch the server:

/usr/local/sbin/LCDd &

./configure --enable-drivers= U

cfontz,curses

make && make install

This brings the display to life, and you

should be treated to your first status

message, telling you that you do not

have an active client. Don’t worry; it is

easy to change that, as LCDproc has a

collection of pre-configured clients. One

of them displays the current system load.

To launch the client, type:

Divide and Conquer

LCDproc comprises two components:

a server that communicates with the

hardware, and a client that tells the

server what to display. The server takes

its defaults from a file called /etc/LCDd.

conf . Check out the directory where

you unpacked LCDproc for a sample

file. You need a few simple modifications

to enable the CFontz driver:

• First delete the line that says

Driver=none or tag this line as a com-

ment.

• Then remove the comment tag at

the start of the Driver=CFontz line.

If your display is an older model –

like mine was – that should complete

the installation steps. More modern

devices, with firmware version 2.0

tar xvzpf lcdproc-0.4.5.tar.gz

puts the installation guide in the

lcdproc-0.4.5 directory. The guide starts

by saying if you’re in a desparate hurry,

type:

/usr/local/bin/lcdproc C &

I use the display for video recording pro-

jects, where it provides a summary of

the date, the channel, and the name of

the program (see Figure 1).

./configure --enable-drivers=all

make

■

And if you start wondering why that

doesn’t work, come back and read the

rest of the file.

Fair enough, but restricting LCDproc

to the drivers you actually need for

your display gives you a more ele-

INFO

[1] LCDproc:

http://lcdproc.omnipotent.net

[2] Crystalfontz:

http://www.crystalfontz.com/

SYSADMIN

Charly Kühnast is a

Unix System Manager

at the data- center in

Moers, near

Germany’s famous

River Rhine. His tasks

include ensuring fire-

wall security and availability and

taking care of the DMZ (demilitarized

zone).

smartmontools ...................... 62

Why wait for a hard drive to fail? The smart-

montools package will warn you about

potential problems.

Admin Workshop

This month we examine cron , at , and

anacron .

Figure 1: LCDproc displaying the channel name on

the LCD attached to my digital video recorder.

www.linux-magazine.com December 2004

The Sysadmin’s Daily Grind: LCDproc

S ervers are often expected to work

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