Home > Articles > Operating Systems, Server > Linux/UNIX/Open Source

  • Print
  • + Share This
Like this article? We recommend

Installing/Upgrading software

The apt subsystem is a packaging system designed for Debian that can speed up installing software. Most free software has a Debian package created, so you can save yourself from the "./configure && make && make install" routine. First you'll want to update the apt-database:

root@not a tty[/]# apt-get update

This will connect to the mirrors specified in /etc/apt/sources.list. Add mirrors closer and faster to you if possible, check the http://www.debian.org/mirror/list for more options. This requires a working internet connection on the host system, as well as an accurate /etc/resolv.conf in the chrooted environment (which is likely not configured). Remember that if you change /etc/resolv.conf in the host environment that's the nameserver that will be used on the bootable CD! Remove internal or private nameservers after configuring the system but before releasing it to the public.

Now that the database is updated, install software is as easy as a single command line:

root@not a tty[/]# apt-get install fluxbox

This command line will attempt to install the Fluxbox4 window manager on your system. If the package does not require any additional packages to be installed, it begins on its own. If additional libraries are necessary, you will be asked to confirm their installation. It will even tell you the approximate amount of space required—good to know when you need to keep the Knoppix system as small as possible. Finally, if the package already exists, you will be informed and then given the option of upgrading (if a new package is available). Finding packages to install can be accomplished by:

root@not a tty[/]# apt-cache search fluxbox

which will provide a list of packages with 'fluxbox' in either their name or description. Use the "apt-get install" command once you find the correct full package name. A more exhaustive search and listing can be found at http://www.debian.org/distrib/packages. Knoppix 3.8 is based off Debian 3.1, also known as 'sarge' or 'stable." If you are using another Knoppix distribution, check /etc/debian_version. Finally, you can also upgrade all the currently-installed packages to their most recent version. Be aware that this will take up a lot of precious space though, as the apt subsystem will often upgrade unnecessary software. Be sure to upgrade before you trim the unneeded pieces below, or upgrade case for each package. Individual packages can be upgraded by running "apt-get install packagename."

Removing packages

You will likely spend more effort removing files than installing new ones. Not only does the compressed filesystem need to fit on a 700MB CD, but every bit must later be uncompressed and either kept in RAM or read from the CD. Running from the CD can be slow since the drive needs to spin up and spin down each time, even just to access simple commands. Modern Knoppix versions have a 'toram' option on their bootscreen that can copy the entire CD to RAM—freeing the CD-ROM drive and greatly improving performance. This, of course, requires a system with enough RAM to hold the filesystem—about 1.7GB for the default distribution—so smaller is better. The basic removal command is:

root@not a tty[/]# apt-get --purge remove packagename

The --purge option will remove the configuration files in /etc and elsewhere that are associated with the package, and is recommended. Otherwise sparse configuration files will be left on the filesystem, not necessarily taking up space, but certainly confusing users and possibly breaking re-installations down the road. Getting a list of all installed packages is done through dpkg-query (the dpkg series of commands all operate on the same subsystem as the apt series, as apt series is an abstraction on top of dpkg):

root@not a tty[/]# dpkg -l


root@not a tty[/]# dpkg-query -W

To get an idea of the size of each application, use:

root@not a tty[/]# dpkg-query -W --showformat="${InstalledSize} 
{$Package}" | sort -n

Working with the Knoppix 3.8 CD, we can see that removing OpenOffice alone will free about 245Mb of installed space. Removing KDE, along with all the internationalizations, will save another 250Mb of uncompressed space. Other packages can be removed at your discretion; using apt-get will ask for confirmation before removing anything unintentional and will take care of the dependencies. Removing packages ending in "-dev" is usually a safe bet, if you do not plan on compiling or developing software with your Knoppix disk. Remove unnecessary locales (language information) through the localepurge program. You may have to install this through apt-get. Afterwards, if you decide you need a different selection, edit /etc/locale.gen to reflect your needs and then run:

root@not a tty[/]# locale-gen
root@not a tty[/]# localepurge

When you have removed all unnecessary packages, use the deborphan command to locate libraries that are no longer required by any package:

root@not a tty[/]# deborphan | xargs apt-get --yes --purge remove

After configuration is complete, clean the system of loose ends that the apt subsystem may have downloaded:

root@not a tty[/]# apt-get clean

Now is the time to restore any configuration files you changed during this portion, such as /etc/resolv.conf or /etc/apt/sources.list. After the system is precisely as you want it to be for your users, you can begin creating the compressed filesystem.

Staying in the chroot jail, execute the following command (type carefully!):

root@not a tty[/]# mkisofs -R -U -v -V "Knoppix ISO9660 FS" -P "Name of Publisher" -p "Name of Creator" -hide-rr-moved -cache-inodes -no-bak -pad -m /KNOPPIX.build/* / | /usr/bin/create_compressed_fs - 65536 > 

Note that the argument after -m is a directory/listing that will be ignored and not put into the filesystem. You can use multiple -m directives to prevent other pieces from going into the filesystem, but this one is required or else you will end up adding your build directory into your final filesystem. The argument after it and before the pipe command is the root directory /, from where the mkisofs program will add files. Lastly, the final argument is the output of the entire process, or the compressed filesystem itself. Go grab a cup of coffee, pick up a magazine, or go for a jog. Compressing the filesystem will take quite some time and be memory and processor-intensive on the host system.

Unmount proc and break out of the chrooted environment:

root@not a tty[/]# umount proc
root@not a tty[/]# exit (or CTRL-D)

Now, change to the directory where you copied the entire CD-ROM. It should now have the compressed filesystem as well. In our example, this would be /knoppix-cd/KNOPPIX/KNOPPIX.build/. There should be two directories, KNOPPIX and boot. Now you can create the final ISO file. One last mkisofs:

root@tty1[KNOPPIX.build]# mkisofs -pad -l -r -J -V "Knoppix disc" -no-emul-boot -boot-load-size 4 –
boot-info-table -b boot/isolinux/isolinux.bin -c boot/isolinux/boot.cat -hide-rr-moved -o knoppix.iso

Once this is complete, burn it with your favorite CD-ROM burning program and you're done. I suggest installing a copy of qemu, a free x86 emulator, similar to VMWare, so that you can test out the ISO before burning a CD. If it is installed it should look like this:

root@tty1[KNOPPIX.build]# qemu -cdrom knoppix.iso
Figure 1

Figure 1 Using Qemu to test an ISO before burning

And you should be able to boot into the CD. Check for any problems thoroughly here and if all is well, move on to creating the physical CD.

In my next article, I will cover the other changes that you can make to your Knoppix CD, including changing the splash screen, upgrading the kernel, and choosing default boot options.

For more information on Linux, visit our Linux Reference Guide or sign up for our Linux Newsletter

  • + Share This
  • 🔖 Save To Your Account

InformIT Promotional Mailings & Special Offers

I would like to receive exclusive offers and hear about products from InformIT and its family of brands. I can unsubscribe at any time.


Pearson Education, Inc., 221 River Street, Hoboken, New Jersey 07030, (Pearson) presents this site to provide information about products and services that can be purchased through this site.

This privacy notice provides an overview of our commitment to privacy and describes how we collect, protect, use and share personal information collected through this site. Please note that other Pearson websites and online products and services have their own separate privacy policies.

Collection and Use of Information

To conduct business and deliver products and services, Pearson collects and uses personal information in several ways in connection with this site, including:

Questions and Inquiries

For inquiries and questions, we collect the inquiry or question, together with name, contact details (email address, phone number and mailing address) and any other additional information voluntarily submitted to us through a Contact Us form or an email. We use this information to address the inquiry and respond to the question.

Online Store

For orders and purchases placed through our online store on this site, we collect order details, name, institution name and address (if applicable), email address, phone number, shipping and billing addresses, credit/debit card information, shipping options and any instructions. We use this information to complete transactions, fulfill orders, communicate with individuals placing orders or visiting the online store, and for related purposes.


Pearson may offer opportunities to provide feedback or participate in surveys, including surveys evaluating Pearson products, services or sites. Participation is voluntary. Pearson collects information requested in the survey questions and uses the information to evaluate, support, maintain and improve products, services or sites, develop new products and services, conduct educational research and for other purposes specified in the survey.

Contests and Drawings

Occasionally, we may sponsor a contest or drawing. Participation is optional. Pearson collects name, contact information and other information specified on the entry form for the contest or drawing to conduct the contest or drawing. Pearson may collect additional personal information from the winners of a contest or drawing in order to award the prize and for tax reporting purposes, as required by law.


If you have elected to receive email newsletters or promotional mailings and special offers but want to unsubscribe, simply email information@informit.com.

Service Announcements

On rare occasions it is necessary to send out a strictly service related announcement. For instance, if our service is temporarily suspended for maintenance we might send users an email. Generally, users may not opt-out of these communications, though they can deactivate their account information. However, these communications are not promotional in nature.

Customer Service

We communicate with users on a regular basis to provide requested services and in regard to issues relating to their account we reply via email or phone in accordance with the users' wishes when a user submits their information through our Contact Us form.

Other Collection and Use of Information

Application and System Logs

Pearson automatically collects log data to help ensure the delivery, availability and security of this site. Log data may include technical information about how a user or visitor connected to this site, such as browser type, type of computer/device, operating system, internet service provider and IP address. We use this information for support purposes and to monitor the health of the site, identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents and appropriately scale computing resources.

Web Analytics

Pearson may use third party web trend analytical services, including Google Analytics, to collect visitor information, such as IP addresses, browser types, referring pages, pages visited and time spent on a particular site. While these analytical services collect and report information on an anonymous basis, they may use cookies to gather web trend information. The information gathered may enable Pearson (but not the third party web trend services) to link information with application and system log data. Pearson uses this information for system administration and to identify problems, improve service, detect unauthorized access and fraudulent activity, prevent and respond to security incidents, appropriately scale computing resources and otherwise support and deliver this site and its services.

Cookies and Related Technologies

This site uses cookies and similar technologies to personalize content, measure traffic patterns, control security, track use and access of information on this site, and provide interest-based messages and advertising. Users can manage and block the use of cookies through their browser. Disabling or blocking certain cookies may limit the functionality of this site.

Do Not Track

This site currently does not respond to Do Not Track signals.


Pearson uses appropriate physical, administrative and technical security measures to protect personal information from unauthorized access, use and disclosure.


This site is not directed to children under the age of 13.


Pearson may send or direct marketing communications to users, provided that

  • Pearson will not use personal information collected or processed as a K-12 school service provider for the purpose of directed or targeted advertising.
  • Such marketing is consistent with applicable law and Pearson's legal obligations.
  • Pearson will not knowingly direct or send marketing communications to an individual who has expressed a preference not to receive marketing.
  • Where required by applicable law, express or implied consent to marketing exists and has not been withdrawn.

Pearson may provide personal information to a third party service provider on a restricted basis to provide marketing solely on behalf of Pearson or an affiliate or customer for whom Pearson is a service provider. Marketing preferences may be changed at any time.

Correcting/Updating Personal Information

If a user's personally identifiable information changes (such as your postal address or email address), we provide a way to correct or update that user's personal data provided to us. This can be done on the Account page. If a user no longer desires our service and desires to delete his or her account, please contact us at customer-service@informit.com and we will process the deletion of a user's account.


Users can always make an informed choice as to whether they should proceed with certain services offered by InformIT. If you choose to remove yourself from our mailing list(s) simply visit the following page and uncheck any communication you no longer want to receive: www.informit.com/u.aspx.

Sale of Personal Information

Pearson does not rent or sell personal information in exchange for any payment of money.

While Pearson does not sell personal information, as defined in Nevada law, Nevada residents may email a request for no sale of their personal information to NevadaDesignatedRequest@pearson.com.

Supplemental Privacy Statement for California Residents

California residents should read our Supplemental privacy statement for California residents in conjunction with this Privacy Notice. The Supplemental privacy statement for California residents explains Pearson's commitment to comply with California law and applies to personal information of California residents collected in connection with this site and the Services.

Sharing and Disclosure

Pearson may disclose personal information, as follows:

  • As required by law.
  • With the consent of the individual (or their parent, if the individual is a minor)
  • In response to a subpoena, court order or legal process, to the extent permitted or required by law
  • To protect the security and safety of individuals, data, assets and systems, consistent with applicable law
  • In connection the sale, joint venture or other transfer of some or all of its company or assets, subject to the provisions of this Privacy Notice
  • To investigate or address actual or suspected fraud or other illegal activities
  • To exercise its legal rights, including enforcement of the Terms of Use for this site or another contract
  • To affiliated Pearson companies and other companies and organizations who perform work for Pearson and are obligated to protect the privacy of personal information consistent with this Privacy Notice
  • To a school, organization, company or government agency, where Pearson collects or processes the personal information in a school setting or on behalf of such organization, company or government agency.


This web site contains links to other sites. Please be aware that we are not responsible for the privacy practices of such other sites. We encourage our users to be aware when they leave our site and to read the privacy statements of each and every web site that collects Personal Information. This privacy statement applies solely to information collected by this web site.

Requests and Contact

Please contact us about this Privacy Notice or if you have any requests or questions relating to the privacy of your personal information.

Changes to this Privacy Notice

We may revise this Privacy Notice through an updated posting. We will identify the effective date of the revision in the posting. Often, updates are made to provide greater clarity or to comply with changes in regulatory requirements. If the updates involve material changes to the collection, protection, use or disclosure of Personal Information, Pearson will provide notice of the change through a conspicuous notice on this site or other appropriate way. Continued use of the site after the effective date of a posted revision evidences acceptance. Please contact us if you have questions or concerns about the Privacy Notice or any objection to any revisions.

Last Update: November 17, 2020