Best of Technical Support
I have written an SMS system in Java. I want to
execute that system as a background service in
Linux. My system is in a *.jar file. How can I do it
as a service in Red Hat?
You need to create a script file that you would put in
the /etc/rc.d/init.d/ directory. It must have a very
specific format, as clearly indicated on this page:
I suggest that you look at other scripts
in that directory to grasp the general format
of the file, especially the first 15 lines or so.
Felipe Barousse Boué
When starting a new service, I like to
copy the init script for SSH, because it's
usually the simplest. Put in whatever commands
you need to run to start your program from the
command line. For example, you might need to set
some environment variables to run a Java program.
Run your init script from the command line to make
sure it starts and stops your new service
correctly, then use your distribution's tool for
managing runlevels to make it run at startup.
Use chkconfig on Red Hat.
I use Webmin and ZoneMinder on my P4 2.2GHz, 1GB RAM system,
and the response is less than what I would expect. Is there a way to
speed up the loopback device?
I just upgraded some Webmin systems to the
latest Webmin, 1.140 at the time of this writing,
and I noticed a substantial speed improvement in
operation. I upgraded all modules as well. All this
was done directly from within Webmin.
Felipe Barousse Boué
The only lag on the loopback device is traversing the TCP stack;
this should be very fast. If you see performance issues, you may want to
look at a program called top (see man top) to see if there are any
It is highly unlikely that the loopback device is the culprit. It's
more probable that there's something else causing the performance lag,
network function or otherwise. Perhaps it's having timeout issues due
to failed DNS lookups or something similar?
I can't get my modem to work. I have a Creative Labs Blaster v92 PCI
internal modem. Linux recognized a Conexant chipset and attempted
to install the driver, but I received an error message. Should I try
installing SuSE Pro 9.0 instead?
Probably the easiest and most advisable solution
is to purchase a very inexpensive modem that is not
a Winmodem. You probably would get a better setup
with less complex stuff, and you will get a modem that
will last for many future Linux generations. Besides,
you will show manufacturers that we all want standard
modems, not proprietary ones.
Felipe Barousse Boué
It's almost never necessary to upgrade your entire operating system
simply to support a device. Without knowing the exact chipset you are
using, I can suggest only that you first determine if yours is a full
hardware modem or a so-called Winmodem. I suspect it is the
latter, because if it were a full hardware modem you probably wouldn't
be having any issues. Rather than updating your Linux distribution,
figure out which driver it was attempting to load and then go to the
Web to find an updated driver. Winmodem support under Linux is
ever-increasing (see www.linmodems.org for a good place to start).
If you are lucky, you will be able to find a newer, working,
version of the driver you are looking for—and save yourself a lot
of trouble to boot.
Are you looking for a tweaky project to help you
understand Winmodems, or do you simply want a Net
connection? Have a goal in mind before you decide
between the above two answers, and remember that if
you upgrade, you may need to redo your modem setup.
I would like to learn Red Hat 9. Can I install Red Hat
9 software and Windows 2003 server (Beta) software
on the same PC? My PC is a Dell PIII with 700MZ,
6GB hard drive and 128MB of RAM. I know I will need to
partition the hard drive. I saw the software for sale
on Amazon.com for about $70 US. I am new to this and
am trying to learn, so any assistance is appreciated.
Yes, you can install Linux and Windows on the
same machine to create what is called a dual-boot system. There are some details to watch,
though. Red Hat 9 has been discontinued so, to play
with Linux and and learn, I would get Fedora Core 1
(Red Hat-sponsored) instead. You can download it
Felipe Barousse Boué
The easiest way to try Linux is download
Knoppix from knoppix.org. This allows you to
try Linux and not impact your hard drive.
Most distributions can be downloaded for free,
including Red Hat 9. You may want to search for a
more up-to-date distribution such as Fedora Core 2.
I haven't personally tried setting up a boot manager with Windows 2003 server and don't intend to, but I have heard of several people doing so successfully. The procedure seems the same as with earlier versions of Windows. Here are the main things you need to be aware of:
1) Knoppix includes QtParted, a free software partition editor. The interface is not as polished, but QtParted does just as good a job of partition editing as PowerQuest's PartitionMagic and other proprietary programs, and you might as well get in the spirit by doing the job with free software. Knoppix, incidentally, makes a great rescue disk.
2) You'll want at least one partition for Linux and another of 125MB for a swap partition. Opinions vary about how to partition, with some people favoring putting the /home, /var and other directories on separate partitions. However, because you're just starting out, perhaps you want to use only one.
3) You might also want a FAT32 partition so that you can share files between your operating systems.
4) If Windows isn't already installed, install it first, right after you partition the drive. Windows does not tolerate another operating system during installation. You can work around the problems, but it's easier just to avoid them altogether.
5) When you're installing, make sure you install the GRUB boot
manager. The installation automatically detects the presence of
Windows, and the boot manager loads when the machine starts and offers
you a menu for choosing which operating system you want to start.
You don't need to resize your existing partitions with a partition editor if you're installing from scratch. All Linux distributions include a basic partitioning tool. If you do use a partition editor, keep in mind that if it fails you may lose important data. Make sure to back up your existing system first, and check that the backup is good before resizing any partition. Alternatively, as Rick Moen suggests, once you have a backup, you might as well just restore it to new partitions and save yourself the partition resizing step entirely.
But, your 6GB drive is too small to run two current operating systems comfortably. You might want to add a new, larger drive for Linux.
Special Reports: DevOps
Have projects in development that need help? Have a great development operation in place that can ALWAYS be better? Regardless of where you are in your DevOps process, Linux Journal can help!
With deep focus on Collaborative Development, Continuous Testing and Release & Deployment, we offer here the DEFINITIVE DevOps for Dummies, a mobile Application Development Primer, advice & help from the experts, plus a host of other books, videos, podcasts and more. All free with a quick, one-time registration. Start browsing now...