Pass the RedHat RHCE RH302 Questions and answers with ExamsMirror

We know that every files/directories are owned by certain user and group. And Permissions are defines to owner user, owner group and other.

-rwxr-x---Full permission to owner user, read and write to owner group and no permission to others.

According to question: We should give the full permission to user user1 without changing the previous permission.

ACL (Access Control List), in ext3 file system we can give permission to certain user and certain group without changing previous permission. But that partition should mount using acl option. Follow the steps

vi /etc/fstab

/dev/hda14/dataext3defaults,acl0 1

Either Reboot or use: mount –o remount /data

setfacl –m u:user1:rwx /data

Verify using: getfacl /data

While you load the X Window System, you will get the problem. To troubleshoot follow the following steps:

1.Check the /tmp is full ?

2.Check your quota, hard limit is already crossed ?

3.Check xfs service is running ?

4.Boot the system on runlevel 3 and execute the system-config-display command

5.Edit the /etc/inittab to set default runlevel 5.

id:5:initdefault:

To understand the role of a boot loader, take a step back from Linux. When you boot your computer, the BIOS starts by detecting basic hardware, including your hard drives. Once it's done, it looks for the boot loader on the Master Boot Record of the first available disk. If you're working with an older PC, the BIOS can't find your boot loader unless it's located within the first 1,024 cylinders of the hard disk.

Newer BIOSes overcome this problem with Logical Block Addressing, which is also known as LBA mode. LBA mode reads 'logical' values for the cylinder, head, and sector, which allows the BIOS to 'see' a larger disk drive.

If you have multiple hard drives, there is one more caveat. If your drives are IDE hard drives, the /boot directory must be on a hard drive attached to the primary IDE controller. If your drives are all SCSI hard drives, the /boot directory must be located on a hard drive with SCSI ID 0 or ID 1. If you have a mix of hard drives, the /boot directory must be located on either the first IDE drive or a SCSI drive with ID 0. In other words, this is not an issue on the Red Hat exams unless the computer that you're tested on has more than two hard drives. And I believe that's less likely, as that would increase the cost of the exam.

If you are getting the Kernel panic error, it means it is boot loader related problem. Redhat Enterprise Linux uses the GRUB boot loader. You can pass the kernel parameter from the boot loader as well as you can correct the kernel parameter passing from boot loader from GRUB screen at boot time.

GRUB boot loader configuration file is: /etc/grub.conf

And Correct Configuration is:

default=0

timeout=5

splashimage=(hd0,0)/grub/splash.xpm.gz

hiddenmenu

title Red Hat Enterprise Linux ES (2.6.9-5.EL)

root (hd0,0)

kernel /vmlinuz-2.6.9-5.EL ro root=LABEL=/ rhgb quiet

initrd /initrd-2.6.9-5.EL.img

Probably miss-configured the boot loader, so giving this problem. You can pass the correct parameter from GRUB prompt:

Table 3-3:GRUB Editing Commands

Command

Description

b

Boot the currently listed operating system

d

Delete the current line

e

Edit the current line

o

Create an empty line underneath the current line

O

Create an empty line above the current line

If you know all parameters and sequence of the boot loader you can enter in command prompt also.

Press c on GRUB screen.

Grub>root (hd0,0)

grub>kernel /vmlinuz-2.6.9-5.EL ro root=LABEL=/ rhgb quiet

grub>initrd /initrd-2.6.9-5.EL.img

grub>boot

Do the following steps as:

1.rpm –ivhftp://server1/example.com/pub/updates/zsh-*

or

1.Login to ftp server : ftpftp://server1.example.comusing anonymous user.

2.Change the directory: cd pub and cd updates

3.Download the package: mget zsh-*

4.Quit from the ftp prompt : bye

5.Install the package

6.rpm -ivh zsh-*

7.Verify either package is installed or not : rpm -q zsh

When user creates the file/directory, user owner will be user itself and group owner will be the primary group of the user.

There is one Special Permission SGID bit, when you set the SGID bit on directory,When users creates the file/directory automatically owner group will be same as a parent directory.

chmod g+s /data

Verify using: ls -ld /data

You will get: drwxrws---

Do the following steps as:

1.usermod -G sysadmin john

2.usermod –G sysadmin jane

3.Verify by reading /etc/group file

Using usermod command we can make user belongs to different group. There are two types of group one primary and another is secondary. Primary group can be only one but user can belongs to more than one group as secondary.

usermod -g groupname usernameTo change the primary group of the user

usermod -G groupname usernameTo make user belongs to secondary group.

Do the following steps as:

1.usermod -G sysuser jackie

2.usermod –G sysuser curtin

3.Verify by reading /etc/group file

Using usermod command we can make user belongs to different group. There are two types of group one primary and another is secondary. Primary group can be only one but user can belongs to more than one group as secondary.

usermod -g groupname usernameTo change the primary group of the user

usermod -G groupname usernameTo make user belongs to secondary group.

Do the following steps as:

1.Open the Browser either firefox or links

2.Type :http://localhost:631

3.Click on Manage Printer

4.Click on Add Printer

5.Type Queue name like stationx and click on continue

6.Type Device type or printing Protocol: i.e Internet printing Protocol

7.Click on Continue

8.Type Device URL: ipp://server1.example.com/printers/printerx

9.Click on Continue

10.Select RAW Model printer

11.Click on Continue

12.Test by sending the printing job

Do the following steps as:

useradd eric

passwd eric

vi /etc/passwd

eric:x:505:505::/home/eric:/sbin/nologin

Which shell or program should start at login time is specified in /etc/passwd file. By default Redhat Enterprise Linux assigns the /bin/bash shell to the users. To deny the interactive login, you should write /sbin/nologin or /bin/false instead of login shell.

Do the following steps as:

1.cat >schedule

*/2 * * * * /bin/echo “Hello World” >/dev/tty8

crontab schedule

Verify using: crontab –l

service crond restart

Cron helps to schedule on recurring events. Pattern of Cron is:

MinuteHourDay of MonthMonthDay of WeekCommands

0-590-231-311-120-7 where 0 and 7 means Sunday.

Note * means every. To execute the command on every two minutes */2.

To add the scheduled file on cron job: crontab filename

To List the Cron Shedule: crontab –l

To Edit the Schedule: crontab –e

To Remove the Schedule: crontab –r