The Top 10 Linux Server Distributions

Rated: The Top 10 Linux server distributions by ease of use, paid support, and data center reliability.
Listed here are the top ten Linux server distributions (aka "Linux server distros") — some of which you may not be aware. The following characteristics, in no particular order, qualified a Linux server distro  for inclusion in this list: Ease-of-use, available commercial support and data center reliability.

1. Ubuntu - At the top of almost every Linux-related list, the Debian-based Ubuntu is in a class by itself. Canonical's Ubuntu surpasses all other Linux server distributions — from its simple installation to its excellent hardware discovery to its world-class commercial support, Ubuntu leaves the others fumbling in the dusty distance.

2. Red Hat - Red Hat Enterprise Linux (RHEL) started out as the "little Linux company that could" and is now a major force in the quest for data center rackspace. The Linux darling of large companies throughout the world, Red Hat's innovations and non-stop support will have you coming back for more.

3. SUSE - Novell-owned SUSE Linux is stable, easy-to-maintain and offers Novell's 24x7 rapid-response support for those who don't have the time or patience for lengthy troubleshooting calls. And, Novell's consulting teams will have you meeting your SLAs and making your accountants happy to boot.

4. Mandriva - For U.S.-based executive or technical folks, Mandriva might be a bit foreign. This incredibly well-constructed Linux distribution hails from France and enjoys extreme acceptance in Europe and South America. It is, as its website claims, a worldwide Linux provider. Its name and its construction derive from the Mandrake Linux and Connectiva Linux distributions.

5. Xandros - If you prefer a Linux server distro with a Microsoft connection, Xandros is the one for you. Rumors aside, Xandros and Microsoft collaborate in what's known in technical circles as "cooperatition." This means that they compete cooperatively. To find out more about this unique perspective, check out the Xandros About page.

6. Slackware - While not generally associated with commercial distributions, Slackware maintains relationships with several companies that provide fee-based support. One of the earliest available Linux server distributions, Slackware has an extensive and faithful fan base. Its developers regularly release new versions.

7. Debian - If you're confused by Debian's inclusion here, don't be. Debian doesn't have formal commercial support but you can connect with Debian-savvy consultants around the world via their Consultants page. Debian has spawned more child distributions than any other parent Linux distribution, including Ubuntu, Linux Mint and Vyatta.

8. Vyatta - Vyatta is more at home on routers and firewalls than PC-based systems, but if you want a commercially-driven distribution for those applications, Vyatta works well for your secure communications needs. Check out the free version of Vyatta Linux.

9. CentOS - It's true that CentOS isn't strictly commercial but since it's based on Red Hat Enterprise Linux (RHEL), you can leverage commercial support for it. CentOS has its own repositories and community support and is not the same as Fedora Linux.

10. Unbreakable Linux - Oracle's Unbreakable Linux is Red Hat Enterprise Linux with some Oracle logos and art added in. Oracle's Unbreakable Linux competes directly with Red Hat's Linux server distributions, and does so quite effectively since purchased support through Oracle is half the price of Red Hat's equivalent model.

 

Cpanel Question and Answers

1)In which primary programming language is cPanel & WHM developed?

Ans:  perl

2) In what directory are custom DNS Zone Templates stored?

Ans:  /var/cpanel/zonetemplates

3)What does the ‘ipcs -s’ command do?

Ans: Shows semaphores

4)In what log file would you find account creation/termination information?

Ans:   /var/cpanel/accounting.log

5)What is the name of the script that you should use to update cPanel & WHM licenses?

Ans:   /usr/local/cpanel/cpkeyclt

6) What does the command ‘hwclock –hctosys’ do?

Ans:  Set the System Time from the Hardware Clock.

7) cPanel & WHM interfaces require Apache to be installed and working.

Ans:    False

8)Which directory contains cPanel & WHM’s error_log file?

Ans:  /usr/local/cpanel/logs

9)It is necessary to obtain a license before installing cPanel & WHM?

Ans: True

10)Where does Tomcat store its log files on a cPanel & WHM server?

Ans:   /usr/local/jakarta/tomcat/logs

11)What is the name of the script you should use whenever you encounter a “License File Expired” message?

Ans:   /usr/local/cpanel/cpkeyclt

12)What file permissions would /usr/bin/gcc have upon disabling WHM’s Compiler Access?

Ans: 750

13)Which of the following files is Pure-FTP’s error log?

Ans:    /var/log/messages

14)What port is used to securely log into webmail?  Please only include the port number in your answer.

Ans:    2096

15)When compiler access is enabled (default), the permissions for /usr/bin/gcc are:

permissions	user	group
-rwxr-xr-x	root	root

When you disable compiler access, cPanel changes the permissions for /usr/bin/gcc:

permissions	user	group
-rwxr-x—	root	compiler

16)What are the four public tiers of cPanel & WHM called?

Ans :  CURRENT,RELEASE,EDGE,STABLE

17)Which file does Tweak Settings save its settings?

Ans : /var/cpanel/cpanel.config

18)If you wanted to trace and/or kill a running process from WHM, which feature should you use?

Ans :     Home »System Health»Process Manager

19)Which of the following commands will output how many emails are in the system’s Exim queue?

Ans :        exim -bpc

20)Which of the following commands will rebuild the RPM database?

Ans :        rpm –rebuilddb

21)If your CentOS server was not able to resolve a domain (cpanel.net for

example), what file would you check and/or add nameservers to help resolve

domains?

Ans :        /etc/resolv.conf

22)What is the full path to the hidden file containing the MySQL root password?

Ans :   /root/.my.cnf

23)What is the directory /home/virtfs used for?

Ans :        Jailshell

24)Which of the following scripts modify images in cPanel & WHM?

/usr/local/cpanel/scripts/upcp

/usr/local/cpanel/bin/update_php_mime_types

/usr/local/cpanel/bin/rebuild_sprites

/usr/local/cpanel/scripts/sa-u

Ans:     /usr/local/cpanel/bin/rebuild_sprites

25)Which of the following directories contains EasyApache’s log files?

Ans:     /usr/local/cpanel/logs/easy/apache

26)If the system log shows repeated connections to TCP port 143, which service is being accessed?

Ans :        IMAP

27)On which port does Tomcat listen by default?

Ans :        8080

28)What is the full path to the script you should run after editing a user file in /var/cpanel/users?

Ans :        /usr/local/cpanel/scripts/updateuserdomains

29)Which of the following scripts would you use to create a new cPanel account

from the command line?

Ans :      /usr/local/cpanel/scripts/createacct

30)What is the secure port for SMTP? (Enter a numeric value.)

Ans :        465

31)Which of the following is the primary daemon responsible for managing

antirelayd, eximstats, cpbandwd and chkservd?

Ans :        tailwatchd

32)Which file contains the MySQL root user’s password on a cPanel & WHM system?

Ans :        /root/.my.cnf

33)Which is the script used to update Apache & PHP?

Ans :        /scripts/easyapache

34)Which of the following commands can you use to securely transfer files between 2 servers.

Ans :        scp

35)What script would you use to manually add an email account from command line?

Ans :        /scripts/addpop

36)Select all of the webmail clients that are included with cPanel.

Roundcube

SquirrelMail

Horde

37)Select the most popular, officially recommended update tier to use.

CURRENT

RELEASE

EDGE

STABLE

Ans:  Release

38)What is the secure port for IMAP? (Enter a numeric value.)

Ans :        993

39)True or False: You can use SFTP for any FTP account created?

Ans :        False

40)True or False: All FTP passwords are stored in /etc/proftpd/.

Ans :        True

41)Which of the following commands (on a RedHat or CentOS system) will display

information about how memory is being used by the server?

cat /proc/meminfo

/usr/sbin/meminfo -a

/usr/bin/memhog -sA

free

Ans :  cat /proc/meminfo

42)True or False: cPanel & WHM requires SELinux to work.

Ans :      False

43)What WHM feature allows you the ability to reconfigure and compile Apache and PHP?

Ans :   EasyApache

44)Which of the following commands will allow you to look through text, one page at a time?

Ans :   less

45)What is the name of the development tool we provide to allow you to interact with cPanel & WHM through your code?

Ans :   cPanel API

46)What is the file that handles PostgreSQL’s configuration settings on a cPanel & WHM server?

Ans :   /var/lib/pgsql/data/postgresql.conf

47)Which directory contains cPanel & WHM’s error_log file?    Blank page error

Ans :   /usr/local/cpanel/logs/error_log

48)What is the name of the script you should use whenever you encounter a “License File Expired” message?

Ans :   /usr/local/cpanel/cpkeyclt

49)In which primary programming language is cPanel & WHM developed?

Ans :   perl

50)Script you can use to install PostgreSQL on a cPanel & WHM server?

Ans :   /scripts/installpostgres

51)Which of the following commands will output how many emails are in the system’s Exim queue?

Ans :   Exim –bpc

52)mod_mono used for?

Ans :   Mod mono is the module needed for the working of ASP in Linux

53)What is the directory /home/virtfs used for?

Ans :   VirtFS provides a jailed shell environment for a user connected to a server via

SSH. Unlike a normal shell environment, a jailed shell environment prevents

access to data outside of the user’s home directory, increasing security for

shell account users.

54)Which two FTP servers are available in cPanel & WHM?

Ans :   Proftp and pure ftp

55)True or False: You can use SFTP for any FTP account created?

Ans :   false

56)What file permissions would /usr/bin/gcc have upon disabling WHM’s Compiler Access?

Ans :     750

57)Which of the following commands will remove or uninstall an RPM?

Ans :   Rpm –e foo

58)What are the four public tiers of cPanel & WHM called?

Ans :   STABLE, RELEASE, CURRENT, EDGE

59)What does the strace utility do?

Ans :   Strace can be a valuable tool when debugging quirky behavior with running unix

or linux processes. It intercepts all signals that a process receives as well

as all system calls the process makes. It can help one understand unusual or

buggy behavior.

60)True or False: Running ‘/usr/local/apache/bin/apachectl -l’ from command line

as root will list modules compiled in Apache.

Ans :   TRUE

61)How would you force cPanel & WHM to update when using the command line

interface? Include the full path in your answer.

Ans :   /scripts/upcp –-force

62)What is the default port for SSH? (Enter a numeric port.)

Ans :   22

63)Where does Tomcat store its log files on a cPanel & WHM server?

Ans :   /usr/local/Jakarta/tomcat/logs

64)In what directory are account Email forwarders stored or saved?

Ans :      /etc/valiases

65)True or False: All FTP passwords are stored in /etc/proftpd/.

Ans :   TRUE

66)What is the secure port for IMAP? (Enter a numeric value.)

Ans :   585

67)Which of the following scripts would you use to create a new cPanel account

from the command line?

Ans: /scripts/wwwacct

68)True or False: cPanel & WHM require Perl to work.

False

69)the most popular, officially recommended update tier to use.

RELEASE

70)If you wanted to change the shared main IP on your cPanel & WHM machine, what

area of WHM would you use to change the IP for all sites and sections?

Ans: WHM >> Main >> Server Configuration >> Basic cPanel & WHM Setup >> The IP

address (only one address) that will be used for setting up shared IP virtual

hosts.

71)What port is used to securely log into webmail?  Please only include the port

Ans:   2096

72)If your CentOS server was not able to resolve a domain (cpanel.net for

example), what file would you check and/or add nameservers to help resolve

domains?

Ans : /etc/resolv.conf

72)What is the full path to the directory that contains YUM repositories on a

cPanel & WHM system?

Ans: cd /etc/yum.repos.d

73)Which of the following directories contains EasyApache’s log files?

Ans: /usr/local/cpanel/logs/easy/apache

74)In what directory are DNS Zone .db files stored by default?

Ans: /var/named/

75)How to manually add email account

Ans: /scripts/addpop

76)What cPanel version is running?

Ans: cat /usr/local/cpanel/version