RED HAT WEBSITE

Disk space can be restricted by implementing disk quotas which alert a system administrator before a user consumes too much disk space or a partition becomes full. Disk quotas can be configured for individual users as well as user groups. This makes it possible to manage the space allocated for user-specific files (such as email) separately from the space allocated to the projects a user works on (assuming the projects are given their own groups).
In addition, quotas can be set not just to control the number of disk blocks consumed but to control the number of inodes (data structures that contain information about files in UNIX file systems). Because inodes are used to contain file-related information, this allows control over the number of files that can be created.

* Features of quotas
1). Limits disk usage (blocks or inodes)
2). Tied to file systems (et on a per file system basis)
3). can be configured for users and groups

* Steps to enable quota support :-
1) Enable quota support per file system in : /etc/fstab
a) defaults,usrquota,grpquota
Example:
#vi /etc/fstab
/dev/Volgroup00/logVol02/home ext3 defaults,usrquota,grpquota 1 2

2) Remount the file system(s)
a) mount -o remount /
b) use 'mount' to confirm that 'usrquota, grpquota' support are enabled
Example:
#mount -o remount /home

3) Create quota database files and generate disk usage table
a) quotacheck -mcug / (where c-create, u-user, g- group)
This creates /aquota.user and aquota.group
b) quotacheck -mavu

4) Assign quota policies:
a) edquota username (set blocks/inodes, soft_limits, hard_limits)
Example:
edquota student1 (sets quotas for user student1)
b) edquota -g devl
(for group quota, check using #quota -g devl)

5) Check quotas
#quota username
Example:
#quota student1

6) Report on usage
#repquota -a

==> The blocks are measured in 1K increments, eg 20000 blocks is roughly 20 MB.

* To change the grace period of quota
#edquota -t

* Managing quotas
If quotas are implemented, they need some maintenance-mostly in the form of watching to see if the quotas are exceeded and making sure the quotas are accurate.

a) Enabling and disabling quotas
i) To turn all user and group quotas off
#quotaoff -vuag
If neither the -u and -g options are specified, only the user quotas are disabled. If only -g is specified, only group quotas are disabled. The -v switches causes verbose status informtion to display as the command executes.
ii) To enable quotas again:
#quotaon -vaug
To enable quotas for a specific file system, such as /home, use the following
#quotaon -vug /home
If neither the -u or -g options are specified, only the user quotas are enabled. If only -g is specified, only group quotas are enabled.

b) Reporting on Disk Quotas
#repquota -a

c) Keeping Quotas accurate
Whenever a file system is not unmounted clearly (due to a system crash, for eg), it is necessary to run quotacheck. Running the following command periodically keeps the quotas more accurate.
#quotacheck -avug
The easiest way to run it periodically is to use cron.

The Yellowdog Updater, Modified (YUM) is an open-source command-line package-management utility for RPM-compatible Linux operating systems and has been released under the GNU General Public License.

4. Install REDHAT ENTERPRISE LINUX 5.x (RHEL5.x) verison on your system.
You can also install VMWARE software and install a RHEL virtual machine on a Windows Terminal.

5. The only matra to pass this exam is " the more you practice, the more you learn ".

6. There are CBT Nuggets Videos tutorials also availabe. These videos are very helpfull. These videos teach you how to install and configure everything. Sometimes you find it lot more easier to learn from videos,rather than reading it from books. So follow whatever method suites you.

7. When you are appearing for the examination, do take one identification proof of yours like voter ID Card or a Driving license.

8. You are not allowed to take anything else in the examination room. So please do not take you vallet, books, mobile phones etc inside the examination lab.

9. While appearing for the qualifying round, make sure that you read the full instructions carefully. Please go through all the qualifying round questions first and then only start the exam. You are given one hour to solve the qualifying section. One thing very important to note here is that you can ask the examiner to check your machine ID and tell if your all the answers are correct. The examiner checks it from his terminal and informs you if you have any incorrect solution. You can then correct it and ask him again. If all your answers are correct he tells you that you have cleared the qualifying section and asks you to leave the room.




10. You cannot discuss or publish the examination questions otherwise Red Hat can cancel your certificate.
Hope you will find the above tips helpfull and will regularly practice to clear this exam with flying colors. Best of Luck.


*** NOTE : I will also post more details about the format of this exam and the minimum marks required to clear the certification. Also post your comments and queries and I will try to reply back with solutions.


FOR MORE INFORMATION CLICK ON THIS LINK--->>> RED HAT WEBSITE

TAGS: rhce, redhat, red hat, redhat certified engineer, linux, rhel, rhel5, rhel5.x, red hat enterprise linux, rhce certification, red hat cert, fedora, unix, certiciation, certification exam


PLEASE DON'T LEAVE THIS BLOG WITHOUT WRITING YOUR COMMENTS

APPEAL:: PLEASE INPUT YOUR THOUGHTS ABOUT THE CONTENT OF THIS BLOG. THIS WILL HELP ME TO WRITE THE KIND OF CONTENTS YOU REQUIRE. THANKS.