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

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

CentOS

Figure 4

Figure 4 CentOS desktop

Origin

Red Hat Open Source code > rebuild of Red Hat AS Enterprise Sources. It's essentially an unofficial community supported Red Hat-style distribution with non-free packages originally in Red Hat replaced with Open Source packages or removed. Its binary packages are built for 100 percent Red Hat compatibility.

Official Purpose of Distro

"CentOS exists to provide a free enterprise class computing platform to anyone who wishes to use it." It's covered here because it's winding up on a significant number of desktops, both in and out of the corporate world.

FAQ Information

Per the FAQ: The kernel is 2.6-18-92, which qualifies as fairly dated. Looking at applications: Inkscape is available in version 0.46-1, which is close enough to the present.

Installation

Download it here. I'm downloading the full 3.7G DVD rather than a liveCD because any time saving from downloading a CD instead of a DVD will be more than paid for when the CD is installed to a hard drive and the first software update grabs most of the content of the DVD.

The following verifies the Gnome standard version:

1539bad48e984ae1441052dc074c0995 CentOS-5.2-i386-bin-DVD.iso
 $ md5sum 

Incredibly slow initial update after installation. It's been downloading for the last 20 minutes, and the progress bar shows it's about halfway through.

Software Installation

Start > Add Remove Packages

This gets you to Package Manager. You can select applications from categories, search on packages, or go to Repositories via the Edit menu. You can add some repositories via the checkbox. Don't add your installer DVD as a repository unless you plan to have it mounted all the time.

Desktop

Typical Gnome. Minimal set of tools, but you can expand them easily enough by adding repositories. (some can be added by check off in the Package Manager.) If you didn't choose KDE in the initial installation, you can add it from Package Manager (it'll be next to Gnome Desktop Environment) afterwards, pick one or the other as a default, and use the other (or mixed applications from both environments) as suits you.

Multimedia/Peripheral Setup

Multimedia

Don't bother unless you're a very experienced Linux user willing to invest an inordinate amount of time in getting your system rolling or you can amortize figuring out how to make this work across a batch of systems in a desktop rollout across a business.

Go here for a command line–based how-to. See what will open in Firefox via mplayer plugin, which will be installed in the above procedure before spending time with individual multimedia apps trying to make them work.

Printer

No driver available for my Canon IP3000, even after a system upgrade. FAIL. The list of supported printers looks like what other distros supported 2 years ago. Check the third-party proprietary driver package to see it support your driver if you're one of the numerous users who won't have supported printers.

Virtualbox setup

Install it as described Part 1 and Part 2 of my "Sun VirtualBox (xVM): A Virtualization Environment for Linux" article. Where the instructions here and the referenced article instructions conflict, use these.

Install kernel-devel and kernel-headers. When you search for these italicized terms in package manager, use the one that matches the actual kernel version displayed in error message when the search is complete. Then install the gcc compiler.

To automatically mount shared folders, this command works perfectly from a root command line:

# mount -t vboxsf win /home/alizard/Desktop/win-1 -o uid=500,gid=500,exec,rw

The above is one line no matter how your browser shows it wrapped. If this doesn't work, make sure the UID and GID match the user's numeric and group Ids.

Add everything after the # to rc.local via the text editor from root:

# nano /etc/rc.local . Save and quit.
# cd /etc/rc.d/rc5.d 
# mv S99local S99zlocal

In this distro, if you examine rc5.d, you will find the following in this order:

S99firstboot
S99rclocal
S99smartd

The rc scripts appear to be run in alphanumeric order because the S99 is the same in all three cases, the run order is determined by the fourth character: f , r, s. Changing the S99 filename via mv with the z in bold inserted as shown moves it to the very end. I think this is required because mounting the shared folder needs to take place after running smartd (a hard disk monitoring and control utility).

Problem: Maxing Out the CPU

A major problem I found is that CentOS sucks up all the available CPU with Virtualbox. From the Virtualbox forums: The problem with that distribution (which it shares with RHEL) is that this kernel uses a 1kHz timer. Handling this amount of timer interrupts in a VM alone needs a relatively large amount of CPU time. Even if the guest is idle.

Kernels with lower-frequency timers are available here. Successfully installing one and reinstalling Guest Additions should make everything work. My first attempt to install a kernel resulted in the OS forbidding me to install an earlier kernel version.

The quick-and-dirty fix (also from that page) is to simply open another guest VM and let it run at idle; having it go to the login prompt worked. Since the quick fix dropped my CPU temp down to under 50, while I believe that the kernel fix will work, I didn't put further effort into replacing the kernel. This fix works on VMware Server; the origin of the modified kernels is an unofficial VMware site.

The Bottom Line

CentOS may have redeeming advantages for the enterprise user in terms of easier administration of lots of boxes or familiarity from the POV of Red Hat–experienced sysadmins. Although I was extremely surprised to see gcc missing from a server-oriented distro. Unless you need something that works only with Red Hat/CentOS or you have an employer or academic institution requiring you to run this distro, I can't think of any good reason for a SOHO desktop user to run it.

  • + 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.

Overview


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.

Surveys

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.

Newsletters

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.

Security


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

Children


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

Marketing


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.

Choice/Opt-out


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.

Links


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