Pass the RedHat RHCE RH302 Questions and answers with ValidTests

It is due to either default runlevel or runlevel specific scripts.

id:?:initdefault:Where default runlevel is specified. It shouldn’t be 6.

l3:3:wait:/etc/rc.d/rc 6It reads the scripts of runlevel 6 while booting system on rulevel 3.

It should be like:

si::sysinit:/etc/rc.d/rc.sysinit

l0:0:wait:/etc/rc.d/rc 0

l1:1:wait:/etc/rc.d/rc 1

l2:2:wait:/etc/rc.d/rc 2

l3:3:wait:/etc/rc.d/rc 3 Should be like this

l4:4:wait:/etc/rc.d/rc 4

l5:5:wait:/etc/rc.d/rc 5

l6:6:wait:/etc/rc.d/rc 6

While you load the X Window System, you will get the problem. Problem may caused by different error.

1.Check the /tmp is full ?

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

3.Check xfs service is running ?

4.Configure the Video card, Resolution, monitor type using: system-config-display (Most Probably in Redhat exam)

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

id:5:initdefault:

Do the following steps as:

1.Use fdisk /dev/hdaTo create new partition.

Type nFor New partition

It will ask for Logical or Primary Partitions. Press l for logical.

It will ask for the Starting Cylinder: Use the Default by pressing Enter Key.

Type the Size: +100MYou can Specify either Last cylinder of Size here.

Press P to verify the partitions lists and remember the partitions name. Default System ID is 83 that means Linux Native.

Type t to change the System ID of partition.

Type Partition Number

Type 82 that means Linux Swap.

Press w to write on partitions table.

Either Reboot or use partprobe command.

mkswap /dev/hda?To create Swap File system on partition.

swapon /dev/hda?To enable the Swap space from partition.

free –mVerify Either Swap is enabled or not.

vi /etc/fstab

/dev/hda?swapswapdefaults0 0

Reboot the System and verify using free command that swap is automatically enabled or not.

Think while Problems occurred on booting System on Runlevel 5 (X Window).

/tmp is full or not

Quota is already reached

Video card or resolution or monitor is misconfigured.

xfs service is running or not.

Do These:

1.df –h /tmp/tmp is full remove the unnecessary file

quota usernameif quota is already reached remove unnecessary file from home directory.

Boot the System in runlevel 3.you can pass the Kernel Argument from boot loader.

Use command: system-config-displayIt will display a dialog to configure the monitor, Video card, resolution etc.

Set the Default Runlevel 5 in /etc/inittab

id:5:initdefault:

6.Reboot the System you will get the GUI login Screen.

When you Boot the System, it starts on default Runlevel specified in /etc/inittab:

Id:?:initdefault:

When System Successfully boot, it will ask for username and password. But you don’t know the root’s password. To change the root password you need to boot the system into single user mode. You can pass the kernel arguments from the boot loader.

Restart the System.

You will get the boot loader GRUB screen.

Press a and type 1 or s for single mode

ro root=LABEL=/ rhgb queit s

System will boot on Single User mode.

Use passwd command to change.

Press ctrl+d

This is boot related problem. There will be same questions repeated two times but problem is different.

First When you restart the system you will get the Error:

File Not Found

mount: error 15 mounting ext3

mount: error 2 mounting none

switchroot: mount failed: 22

umount /initrd/dev/: 2

Kernel Panic: no syncing: Attempted to kill init !

Restart the System

Check the grub boot loader configuration by pressing e shortcut key.

You will see like:

root (hd0,0)

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

initrd /initrd-2.6.9-5.EL.img

OR

root (hd0,0)

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

initrd /initrd-2.6.9-5.EL.img

Then Edit Boot loader to make like

root (hd0,0)

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

initrd /initrd-2.6.9-5.EL.img

Check all lines and edit as same as above. Press b to boot the system

After booting the system you should correct the /etc/grub.conf file.

If still you are getting Error likeFile not found, it seems that either kernel file or initrd file is missing. To troubleshoot with these problem, boot the system on rescue mode.

linux rescue

chroot /mnt/sysimage

Check the files on /boot, if not available install the kernel package from ftp or nfs server

Create the initrd image file on boot using: mkinitrd initrd-2.6.9-5.EL.img `uname –r`

Do the following steps as:

1. Use fdisk /dev/hdaTo create new partition.

Type nFor New partition

It will ask for Logical or Primary Partitions. Press l for logical.

It will ask for the Starting Cylinder: Use the Default by pressing Enter Key.

Type the Size: +100MYou can Specify either Last cylinder of Size here.

Press P to verify the partitions lists and remember the partitions name. Default System ID is 83 that means Linux Native.

Type t to change the System ID of partition.

Type Partition Number

Type 82 that means Linux Swap.

Press w to write on partitions table.

Either Reboot or use partprobe command.

mkswap /dev/hda?To create Swap File system on partition.

swapon /dev/hda?To enable the Swap space from partition.

free –mVerify Either Swap is enabled or not.

vi /etc/fstab

/dev/hda?swapswapdefaults0 0

Reboot the System and verify that swap is automatically enabled or not.

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

In Network problem thinks to check:

IP Configuration: use ifconfig command either IP is assigned to interface or not?

Default Gateway is set or not?

Hostname is set or not?

Routing problem is there?

Device Driver Module is loaded or not?

Device is activated or not?

Check In this way:

use ifconfig command and identify which IP is assigned or not.

cat /etc/sysconfig/networkWhat, What is written here. Actually here are these parameters.

NETWORKING=yes or no

GATEWAY=x.x.x.x

HOSTNAME=?

NISDOMAIN=?

Correct the file

Use vi /etc/sysconfig/network-scirpts/ifcfg-eth0 and check the proper options

DEVICE=eth0

ONBOOT=yes

BOOTPROTO=static

IPADDR=x.x.x.x

NETMAKS=x.x.x.x

GATEWAY=x.x.x.x

Use service network restart or start command

Do the following steps as:

Boot the system in Single user mode

Use the passwd command