Wednesday, July 7, 2010

Benefits of using BCC field while sending emails

Almost all of us sends/receives numbers of emails per day. But only few people are aware of BCC and its advantages, while sending email. If you are still unaware of what is BCC then this is the right post to explore yourselves.

What is BCC?

BCC stands for Blind Carbon Copy. It helps us to send email address to multiple recipients. Normally we send multiple email by seperating with a comma or semi-colon in the TO, Cc or BCC field.

If you are using the TO field, the receiver is able to view the full information of recipient email address to which the email was send. In another word, the receiver can see whom else the email was sent.

If you are using the BCC field to send the multiple email then this option allows you to hide the recipients in email messages. In another word, the receiver will not be able to see the list of recipient email addresses. This could be a secure way to hide the list of recipients.

Why should you use BCC?

Privacy: BCC provides an easy and simple option for protecting the privacy of your recipients. Under many circumstances it is necessary for us send an email without letting the recipients know who else is receiving the same message. Also it is highly recommended that you use the BCC: while forwarding a joke or a funny email to a list of your friends. If you are sending email on behalf of a business or organization, it may be especially important to keep lists of clients, members, or associates confidential. So don’t forget to use BCC: in instances wherever privacy matters.

How to BCC an email message?

Most email clients provide the BCC: option under a few lines below the To: field. All you have to do is just enter the list of recipients in the BCC: field instead of entering in the To: field. You may enter only your own email address in the To: field. Once you do this just hit the Send button.

The moral is that you should use BCC: while sending bulk messages so as to protect the privacy of your recipients.

Tuesday, June 29, 2010

RHCE exam sample questions paper

Here is the sample RHCE questions. This may be a bit outdated but is very good for RHCE exam prepration. Good luck!!!!

Installation and Configuration
Total Duration: 3.0 hours
Goal: To demonstrate the ability to install and configure a Red Hat Enterprise Linux
system and implement network services and security.

You have been instructed to install Red Hat Enterprise Linux on a system within your organization. The
system must be configured with a set of locally-defined administrators and bound to an NIS domain, RHCE,
for additional user accounts. Your machine will be a member of the DNS domain All systems
in the DNS domain are in the subnet, and all systems in that subnet
are in
Perform the tasks listed below. You should read the entire list before you begin. In order to fulfill the
printing requirement, you will probably need to install the X Window System.
Your system will be rebooted before it is graded, so make sure that all changes you implement are persistent
across reboots. You should also be aware the scoring items will be evaluated by whether they work as
specified. Consequently, a correctly configured networking service will earn no points if networking itself is
broken. is accessible by ssh for testing the availability of network services on your system.
If your hostname is, then you can log in to this system with the username guest1
and the password of password. If, then you can log in as guest2 with the same
password, and so on. You will not be able to log in successfully to any other account on that system.
Additional information on how you might use this system may be included with specific requirements below.
The requirements for this section include configuration of security restrictions on various network services.
You should be aware that making the services available for permitted hosts and networks is a higher priority
than restricting any prohibited networks, because you will not receive credit for successful configuration of
services if the implemented restrictions block access to permitted hosts and networks. If you choose to use
kernel level firewalling, you must REJECT rather than DROP unwanted packets.
Be aware that you are not permitted to communicate with other examinees during the course of this exam.
You are also prohibited from connecting to the hosts of other examinees. The testing system and the network
will be monitored, and misuse of either will result in a grade of zero on this section.
Installation Instructions

• Install Red Hat Enterprise Linux on the examination system using the following source for the instal-
lation media:

• Once your system is installed the distribution is available via YUM:

The examiner will provide a suitable boot medium to begin the installation.

• Installation options should be chosen as follows:
– Use DHCP to configure networking for eth0.
– Install the boot loader to the Master Boot Record (MBR) – do not include any additional options
for the bootloader to pass to the kernel unless instructed to do so by the examiner
– Set the root password to rW9ySX.
– The timezone should be appropriate for your locale, and the system clock should be set to UTC.
– Skip entering an Installation Number.
– Do not attempt to register the system with Red Hat Network.
– Consult the instructions concerning parititioning in the next section before you begin your instal-

Perform all of the following steps. When you receive your results, these items will be reported as a sin-
gle score identified as RHCT. You must score 70 or higher on these RHCT requirements in order to earn

• Complete the form at Provide your name as you
wish to have it appear on your certificate (should you earn it) and the email address you wish for us to
use when contacting you with your results. Red Hat Global Learning Services requires this information
to process and report your results.

• Install the dialog RPM package.

• Partition the system’s primary hard drive using the following scheme:
/boot 256 MB
/ 1024 MB
/home 512 MB
/usr 2048 MB
/var 512 MB
swap 1.5 - 2 times memory reported in /proc/meminfo
/shared Use the remaining space to create a RAID 0 set on /dev/md0
If you do not know how to create the RAID 0 set for /shared, you must create it as a separate directory.
You may create the RAID 0 set at install time or post-installation as you prefer.

• SELinux must be running in the Enforcing mode.

• Create the following users, groups, and group memberships:
– A group named sysusers
– A user andrew who belongs to sysusers as a secondary group
– A user susan who also belongs to sysusers as a secondary group
– A user brad who does not have access to an interactive shell on the system, and who is not a
member of sysusers
– andrew, susan, and brad should all have the password of password

• Create a collaborative directory /shared/sysusers with the following characteristics:

– Group ownership of /shared/sysusers is sysusers
– The directory should be readable, writable, and accessible to members of sysusers, but not to
any other user. (It is understood that root has access to all files and directories on the system.)
– Files created in /shared/sysusers automatically have group ownership set to the sysusers

• Install the appropriate kernel update from The following
criteria must also be met:
– The updated kernel is the default kernel when the system is rebooted
– The original kernel remains available and bootable on the system

• Enable IP forwarding on your machine.

• Set up the default local print queue to forward jobs to the IPP (CUPS) print queue stationx on, where x is your station number. Configure this printer as a “Generic – text-
only” print queue.
Note: The queue stationx on server1 dumps print jobs into the file http://server1/printers/stationx.
This file can be examined to confirm that you have configured the print queue correctly.

• The user andrew must configure a cron job that runs daily at 15:25 local time and executes
– /bin/echo hello

• Bind to the NIS domain RHCE provided by for user authentication. Note the following:
– nisuserx should be able to log into your system, where x is your station number, but will not have
a home directory until you have completed the autofs requirement below
– All NIS users have a password of password

• Configure autofs to automount the home directories of NIS users. Note the following:
– ( NFS-exports /rhome/stationx to your system, where
x is your station number
– nisuserx’s home directory is
– nisuserx’s home directory should be automounted locally beneath /rhome as /rhome/nisuserx
– home directories must be writable by their users
– While you are able to log in as any of the users nisuser1 through nisuser20, the only home
directory that is accessible from your system is nisuserx.
Example: station100 would configure the automounter such that nisuser100’s home directory
/rhome/nisuser100 gets mounted automatically upon login. The NFS share would be

• Copy the file /etc/fstab to /var/tmp. Configure the permissions of /var/tmp/fstab so that:
– the file /var/tmp/fstab is owned by the root user.
– the file /var/tmp/fstab belongs to the group root.
– the file /var/tmp/fstab should not be executable by anyone.
– the user andrew is able to read and write /var/tmp/fstab.
– the user susan can neither write nor read /var/tmp/fstab.
– all other users (current or future) have the ability to read /var/tmp/fstab.

• Configure your system so that it is an NTP client of

RHCE (Network Services and Security) Requirements

Perform all of the following steps. When you receive your results, these items will be reported as a sin-
gle score identified as RHCE. You must score 70 percent on the RHCE requirements in order to earn RHCE.
You will note that some requirements specify that a service should not be available from the DNS domain (that’s m-y-one-three-three-t). All systems in that domain are in the
subnet, and all systems in that subnet are in

• Configure SSH access as follows:
– susan has remote SSH access to your machine from within
– Clients within should NOT have access to ssh on your system

• Configure POP3 email on your system according to these criteria:
– brad must be able to retrieve email from your machine using POP3 from within
– Clients within the domain should not have access to your POP3 service

• Configure FTP access on your system:
– Clients within the domain should have anonymous FTP access to your machine
– Clients outside should NOT have access to your FTP service

• Share the /shared directory via SMB:
– Your SMB server must be a member of the SMBGROUP workgroup
– The share’s name must be shared
– The shared share must be available to domain clients only
– The shared share must be browseable
– susan must have read access to the share, authenticating with the same password password, if

• Implement a web server for the site, then perform the following steps:
– Download
– Rename the downloaded file to index.html
– Copy this index.html to the DocumentRoot of your web server
– Do NOT make any modifications to the content of index.html

• Export your /shared directory via NFS to the domain only.
Note: because you will not have root access, you will not be able to directly mount your exported
/shared directory using your guest account on the system provided for testing. However, the auto-
mounter on the system has been configured such that it will automount your /shared directory under
/home/guestx/nfs/stationx, where x is your station number. Consequently, successful execution of
ls /home/guestx/nfs/stationx indicates that the automounter was able to automount your NFS

• Configure an email alias for your MTA such that mail sent to acctmgr is received by the local user

• Configure SMTP mail service according to the following requirements:
– Your mail server should accept mail from remote hosts and localhost
– susan must be able to receive mail from remote hosts
– Mail delivered to susan should spool into the default mail spool for susan, /var/spool/mail/susan.

Additional RHCE Requirements

Perform any two of the following steps. Completion of more than two will not result in extra credit. If
time allows, you may wish to complete more than the minimum just in case one of your tasks does not meet
our specifications. Please note that these additional items are part of your RHCE-specific score.

• Provide SSL-encapsulated IMAP access (IMAPS):
– IMAPS must be available to brad from
– IMAPS must NOT be available to other networks or domains.
– The SSL certificate for the IMAPS server must be created as follows:

• Use the defaults for Country, State, Locality, and Organization Name

• Set Organizational Unit to GLS

• Set Common Name to

• Set Email Address to

• Implement a web proxy server bound to port 8080.
– Clients within should have access to your proxy server
– Clients outside of should NOT have access to your proxy server

• Extend your web server to include a virtual host for the site, where x is
your station number, then perform the following steps:
– Set the DocumentRoot to /var/www/virtual
– Download
– Rename the downloaded file to index.html
– Place this index.html in the DocumentRoot of the virtual host
– Do NOT make any modifications to the content of index.html
– Ensure that susan is able to create content in /var/www/virtual

Note: The original web site must still be accessable. DNS resolution
for the hostname is already provided by the name server on

Monday, May 17, 2010

How to use webcam in fedora?

Cheese is a fun tool that lets you play around with your webcam. You can take photos, take multiple photos in burst, or you can take movies with it. You can also apply special effects. So for example - you can turn yourself into the Hulk. Or, you can trip out! There's a lot of different effects, and you can combine them all at same time which sometimes results in kind of an interesting picture. Every time you take a photo it ends up in a little bar along the bottom. All your photos are also stored in you home directory, in the Pictures > Webcam directory. So, there's always there, and you don't even have to open up Cheese to access them. You can right-click and open them right away or you can edit them up in the Gimp.

How to install cheese in my fedora machine?

Cheese is already installed when you install your OS. If you need to install it later then just type the following command in your terminal.

sudo yum -y install cheese


Friday, May 14, 2010

How to install fedora 12 from usb drive?

If you don't have a CD-ROM, DVD drive and want to install fedora 12 then here are some easy steps you need to follow. Most of the netbooks come without optical drives which can be challenging to install an operating system on them. If you don't have an external CD-ROM or DVD-ROM drive then booting from an usb stick would be your best solution.

Here I am going to show you how easy it is to install an Operating System(OS) from a usb drive. As fedora is my best choice of OS, I am going to show you how to install(Fedora 12) using a pen drive. All you need to do is follow these simple steps.

1) Download Fedora 12 DVD image

First of all you need to download an ISO image depending on you system architecture, Fedora-12-i386-DVD.iso or Fedora-12-x86_64-DVD.iso.

(* If you already have the image you can skip this process)

2) Download Fedora 12 live cd iso image

Download live cd image depending on you system architecture, Fedora-12-i386-netinst.iso or Fedora-12-x86_64-netinst.iso.

3) Create a single ext3 bootable partition on the usb drive. You can use gparted or command line to do this task. I used command line, so here are the steps to create a partition on the usb disk(For Newbie).

$ sudo su - Switch to root
# fdisk /dev/sdb (Here sdb is the device name of your usb drive)
(Here: 'd' to delete the existing partition
'n' to create a partition
'a' to mark the partition as bootable
'w' write table to disk and exit)

# mkfs.ext3 /dev/sdb1 Fromat the partition with ext3 filesystem

4) Install Fedora-12-i386-netinst.iso in USB disk.

# livecd-iso-to-disk /path/to/Fedora-12-i386-netinst.iso /dev/sdb1

( *Note: --reset-mbr flag should be added to the livecd-iso-to-disk command line for some machine to boot from usb stick.)

5) Mount the Fedora-12-i386-DVD.iso image and copy the images/ folder to your usb stick.

# mkdir /mnt/dvd-image
# mount -t iso9660 /path/to/Fedora-12-i386-DVD.iso /mnt/dvd-image -o loop
# mkdir /mnt/usb-drive
# mount /dev/sdb1 /mnt/usb-drive
# cp -rp /mnt/dvd-image/images /mnt/usb-drive
# umount /mnt/dvd-image

6) Copy DVD iso image to the USB drive

# cp /path/to/Fedora-12-i386-DVD.iso /mnt/usb-drive
# umount /mnt/usb-drive

7) Reboot the system with USB drive.