Correct Answer: D

Mount the DVD iso of the desired update of Oracle Linux Release 5. Use the following command for mounting the DVD media inserted in /dev/cdrom

# mount -r -o loop -t iso9660 /dev/cdrom /mnt

Use following command to mount iso image file

# mount -o loop /mnt

Correct Answer: A

* A permission of "2755" for a directory means that everyone has read and execute permission, while the

file owner and members of the file's group additionally have write permission. And any files or

subdirectories created in that directory will inherit the parent directory's group id.

Incorrect:

Not D: chmod 2775 is a valid command.

Correct Answer: A

A configuration file exists for the purpose of persisting changes, named /etc/sysct1.conf. When booting, your server starts the procps service that reads this configuration file and applies all settings in it.

Note:

* If you've ever needed to change the hostname for Red Hat Linux, CentOS or similar operating systems, you can do so easily with one simple command.

Just use the echo command to replace the contents of /proc/sys/kernel/hostname with your new host

name.

# echo hostname.com > /proc/sys/kernel/hostname

Then restart the network interfaces:

# /etc/init.d/network restart

Shutting down interface venet0: [ OK ]

Shutting down loopback interface: [ OK ]

Bringing up loopback interface: [ OK ]

Bringing up interface venet0: RTNETLINK answers: File exists RTNETLINK answers: File exists

[ OK ]

Now you can use the hostname command to verify that it has changed.

Correct Answer: D

*

strace - trace system calls and signals

In the simplest case strace runs the specified command until it exits. It intercepts and records the system calls which are called by a process and the signals which are received by a process. The name of each system call, its arguments and its return value are printed on standard error or to the file specified with the -o option.

*

strace is a useful diagnostic, instructional, and debugging tool. System administrators, diagnosticians and trouble-shooters will find it invaluable for solving problems with programs for which the source is not readily available since they do not need to be recompiled in order to trace them. Students, hackers and the overly-curious will find that a great deal can be learned about a system and its system calls by tracing even ordinary programs. And programmers will find that since system calls and signals are events that happen

at the user/kernel interface, a close examination of this boundary is very useful for bug isolation, sanity

checking and attempting to capture race conditions.

Each line in the trace contains the system call name, followed by its arguments in parentheses and its

return value. An example from stracing the command ''cat /dev/null'' is:

open("/dev/null", O_RDONLY) = 3

Errors (typically a return value of -1) have the errno symbol and error string appended. open("/foo/bar",

O_RDONLY) = -1 ENOENT (No such file or directory) Signals are printed as a signal symbol and a signal

string. An excerpt from stracing and interrupting the command ''sleep 666'' is:

sigsuspend([]

--- SIGINT (Interrupt) --+++ killed by SIGINT +++

Reference: man strace

Correct Answer: C

yum list installed [glob_exp1] [...]

List the packages specified by args. If an argument does not match the name of an available package, it is

assumed to be a shell-style glob and any matches are printed.

Incorrect:

Not A:

info

Is used to list a description and summary information about available packages

Not B:

search

This is used to find packages when you know something about the package but aren't sure of it's name. By

default search will try searching just package names and summaries, but if that "fails" it will then try

descriptions and url.

Not D: check

Checks the local rpmdb and produces information on any problems it finds.

Correct Answer: BCD

BC:

* A kickstart installation requires a kickstart file that contains the answers to every question asked during an interactive installation. Kickstart files can be created in one of three ways:

/ Perform an interactive installation. Once complete you will find the Kickstart configuration file for the

installation you just completed in the "/root/anaconda-ks.cfg" file. This can be amended and used for

subsequent installations. (B)

/ Create a Kickstart file in a text editor manually, or based on a copy of a previous file.

/ Use the Kickstart Configurator. (C)

D:

* Kickstart installations provide an automated alternative to the normal interactive installations of RHEL and Oracle Linux. The automation of installation and post installation configuration steps represents a considerable time saving in situations where many similar installations are performed.

Reference: Kickstart - Automated Installations of RHEL and Oracle Linux

Correct Answer: C

top - display Linux tasks

The top program provides a dynamic real-time view of a running system. It can display system summary

information as well as a list of tasks currently being managed by the Linux kernel. The types of system

sum- mary information shown and the types, order and size of information displayed for tasks are all user

configurable and that configuration can be made persistent across restarts.

Incorrect:

Not A, Not B:

ps displays information about a selection of the active processes.

To see every process on the system using standard syntax:

ps -e

ps -ef

ps -eF

ps -ely

To see every process on the system using BSD syntax:

ps ax

ps axu

Not D: meminfo - provide information about memory

The meminfo() function provides information about virtual and physical memory particular to the calling

process. The user or developer of performance utilities can use this information to analyze system memory

allocations and develop a better understanding of the factors affecting application performance.

Correct Answer: AC

Network bonding refers to the combination of network interfaces on one host for redundancy and/or increased throughput.

Correct Answer: B

Execute a cron job every 5 Hours

The second field is for hours. If you specify * in this field, it runs every hour. If you specify */5 in the 2nd field, it runs every 5 hours as shown below. 0 */5 * * * /home/ramesh/backup.sh

Correct Answer: A

*

The command rpm -q --changelog rpm displays a detailed list of information (updates, configuration, modifications, etc.) about a specific package. This example shows information about the package rpm. However, only the last five change entries in the RPM database are listed. All entries (dating back the last two years) are included in the package itself. This query only works if CD 1 is mounted at /media/cdrom:

rpm -qp --changelog /media/cdrom/suse/i586/rpm-3*.rpm

*

Is the patch RPM suitable for my system?

To check this, first query the installed version of the package. For pine, this can be done with

rpm -q pine pine-4.44-188

Incorrect: not C:

* qa stands for "Query All"

Assuming you are attempting to find out if you have the Very Secure FTP Daemon installed, you want:

rpm -qa | grep vsftp

rpm -qa will show you all installed RPMs, piping it through grep will limit the list to RPMs containing the

string "vsftp".