RH302 Sample Questions Answers

IMAP is a very usefully protocol, but it lacks encryption. The dovecot package distributed with RHEL includes the ability to use IMAP over SSL, This requires the creation of a PEM format certificate.

cd /etc/pki/tls/ and remove the cert.pem.

Go the /etc/pki/tls/certs then use:

make dovecot.pem : Which generates the dovecot.pem certificate by reading MakeFile

Enable the imaps with Certificate and Key file protocol from /etc/dovecot.conf

vi /etc/dovecot.conf

protocols = imap imaps

ssl_cert_file = /etc/pki/dovecot/certs/dovecot.pem

ssl_key_file = /etc/pki/dovecot/private/dovecot.pem

service dovecot restart : Restart the Dovecot service

Outside the LAN means my133t.org. All host on exam on example.com domain and outside domain means cracker.org.

To block the mail coming from cracker.org

1.vi /etc/mail/access

@my133t.orgREJECT

2.service sendmail start | restart

3.chkconfig sendmail on

Do the following steps as:

1.vi /etc/vsftpd/ftpusers

user1

user2

2.service vsftpd start| restart

Using /etc/vsftpd/ftpusers file we can deny to certain users to access files via ftp. As wellas there is another file named /etc/vsftpd.user_list can be used to allow or to deny to users.

Slave DNS is the backup of master DNS. Automatically within a certain time slave DNS synchronizes with the Master DNS server.

1.vi /var/named/chroot/etc/named.conf

zone “example.com” IN {

type slave;

masters { 192.100.0.254; };

file “example.com.zone”;

};

named-checkconf command checks the syntax for /var/named/chroot/etc/named.conf file.

service named start | restart

Do the following steps as:

1.vi /etc/hosts.deny

sshd:ALL EXCEPT .example.com

or

1.vi /etc/hosts.deny

sshd:ALL

2.vi /etc/hosts.allow

sshd:.example.com

We can secure the services using tcp_wrappers. There are main two files, /etc/hosts.allow and /etc/hosts.deny.

There will be three stage access checking

- Is access explicitly permitted? Means permitted from /etc/hosts.allow?

- Otherwise, Is access explicitly denied? Means denied from /etc/hosts.deny?

- Otherwise, by default permit access if neither condition matched.

To deny the services we can configure /etc/hosts.deny file using ALL and EXCEPT operation. Pattern of /etc/hosts.allow and /etc/hosts.deny file is:

Demon_list:client_list:options

In Client list can be either domain name or IP address.

Do the following steps as:

1.vi /etc/xinetd.d/telnet

service telnet {

only_from=192.168.0.0/24

access_times=09:00-17:00

}

2.chkconf telnet on

3.service xinetd restart

xinetd based services can manage by specifying host and time parameters. Only_from means connection allowed network, remaining hosts explicitly deny. access_times specify when service is available.

Do the following steps as:

1.ftp ftp://server1.example.com

2.Login as an anonymous and download the file.

3.Copy the file in /var/www/html if you downloaded in another location.

4.service httpd restart

5.Test using links: links http://station?.example.com

Check the SELinux context of index.html file, should like this:

-rw-r--r-- root root system_u:object_r:httpd_sys_content_t /var/www/html/index.html

If SELinux Context is mismatched, use the restorecon –R /var command

Do the following steps as:

1. vi /etc/mail/virtusertable

accountmanager@jeff

2. service sendmail restart

Do the following steps as:

1.vi /etc/samba/smb.conf

[global]

netbios name=station?

workgroup=station?

security=user

smb passwd file=/etc/samba/smbpasswd

encrypt passwords=yes

hosts allow= .example.com

[data]

path=/data

public=no

writable=no

browsable=yes

2.smbpasswd -a eric

3.service smb start

4.chkconfig smb on

/etc/samba/smb.conf. There are some pre-defined section, i. globaluse to define the global options, ii. Printersuse to share the printers, iii. homesuse the share the user’s home directory.

Security=uservalidation by samba username and password. May be there are other users also. To allow certain share to certain user we should use valid users option.

smbpasswdHelps to change user’s smb password. –a option specifies that the username following should be added to the local smbpasswd file.

Do the following steps as:

1.vi /etc/httpd/conf/httpd.conf

<VirtualHost 192.100.0.1>

ServerNamewww.abc.com

DocumentRoot /var/www/abc/

<Directory /var/www/abc>

AllowOverrideauthconfig

</Directory>

DirectoryIndexindex.html

ServerAdminwebmaster@abc.com

ErrorLog logs/error_abc.logs

CustomLog logs/custom_abc.logs common

</VirtualHost>

2.Create the directory and index page on specified path. (Index page can download fromftp://server1.example.comat exam time)

3.vi /var/www/abc/.htaccess

AuthName“Only to Authorized Users”

AuthTypebasic

AuthUserFile/etc/httpd/conf/mypasswd

requirevalid-user

htpasswd –c /etc/httpd/conf/mypasswd user5

htpasswd –m /etc/httpd/conf/mypasswd user6

chgrp apache /etc/httpd/conf/mypasswd

chmod g+r /etc/httpd/conf/mypasswd

service httpd restart

chkconfig httpd on

AllowOverride Authconfig is used to specify which and how much configuration can be overridden by directory specific .htaccess files.

One of the most common tasks performed in users’ .htaccess files is adding authorization. Typically, a user will setup authorization for directories that hold sensitive information with a configuration.

IMAP is a very usefully protocol, but it lacks encryption. The dovecot package distributed with RHEL includes the ability to use IMAP over SSL, This requires the creation of a PEM format certificate.

cd /usr/share/ssl/certs

make dovecot.pem : Which generates the dovecot.pem certificate by reading MakeFile

Enable the imaps protocol from /etc/dovecot.conf

vi /etc/dovecot.conf

protocols = imap imaps

service dovecot restart : Restart the Dovecot service

Do the following steps as:

1.vi /etc/security/time.conf

login;*;user1|user2|user3;Al0900-1700

2.vi /etc/pam.d/login

accountrequiredpam_time.so

For Time based authentication, we should configured in /etc/security/time.conf

Syntax of /etc/security/time.conf

services;ttys;users;times

services

is a logic list of PAM service names that the rule applies to.

ttys

is a logic list of terminal names that this rule applies to.

users

is a logic list of users to whom this rule applies.

times

the format here is a logic list of day/time-range entries the days are specified by a sequence of two character entries, MoTuSa for example is Monday Tuesday and Saturday. Note that repeated days are unset MoMo = no day, and MoWk = all weekdays bar Monday. The two character combinations accepted are

Mo Tu We Th Fr Sa Su Wk Wd Al

the last two being week-end days and all 7 days of the week respectively. As a final example, AlFr means all days except Friday.

pam_time modules checks the file /etc/security/time.conf for authentication. So, we should call the pam_time modules in /etc/pam.d/login.

Do the following steps as:

1.visudo

# User alias Specification

User_alias LIMITEDTRUST=peter

# Cmnd alias Specification

Cmnd_alias MINIMUM=/usr/sbin/useradd, /usr/bin/passwd, /usr/sbin/groupadd, /usr/sbin/userdel, /usr/sbin/groupdel, /usr/sbin/usermod

#User Privilege Specification

LIMITEDTRUST ALL=MINIMUM

2.Login as peter user and run sudo useradd username

Using Sudo we can give root level privilege on commands. Visudo is the sudo editor. In user alias Specification we create the user alias and in Cmnd alias Specification, we create the command alias. In User Privilege Specification section, list the users, groups allowed to use the sudo.

Do the following steps as:

1.vi /etc/security/limits.conf

user1,user2-maxlogins1

@training-maxlogins5

2.vi /etc/pam.d/system-auth

sessionrequired/lib/security/pam_limits.so

To limit the number of process or number of logins, we should configure on /etc/security/limits.conf. First Columns contains the username separated by comma or @group name. Second column either hard or soft limits. Third columns called the item, maxloigns or nproc etc.

To identify the session of users we should call the pam_limits module in /etc/pam.d/system-auth.

Do the following steps as:

1.vi /etc/xinetd.d/telnet

service telnet {

only_from=192.168.0.0/24

access_times=09:00-17:00

}

2.chkconf telnet on

3.service xinetd restart

xinetd based services can manage by specifying host and time parameters. Only_from means connection allowed network, remaining hosts explicitly deny. access_times specify when service is available.

Do the following steps as:

1.vi /etc/hosts.deny

sshd:ALL EXCEPT .example.com

or

1.vi /etc/hosts.deny

sshd:ALL

2.vi /etc/hosts.allow

sshd:.example.com

We can secure the services using tcp_wrappers. There are main two files, /etc/hosts.allow and /etc/hosts.deny.

There will be three stage access checking

- Is access explicitly permitted? Means permitted from /etc/hosts.allow?

- Otherwise, Is access explicitly denied? Means denied from /etc/hosts.deny?

- Otherwise, by default permit access if neither condition matched.

To deny the services we can configure /etc/hosts.deny file using ALL and EXCEPT operation. Pattern of /etc/hosts.allow and /etc/hosts.deny file is:

Demon_list:client_list:options

In Client list can be either domain name or IP address.

Do the following steps as:

1.touch /etc/nologin

2.vi /etc/securetty

comment all available terminall then first.

If /etc/nologin file is created, then pam modules pan_nologin deny to all non-root users to login locally.

/etc/pam.d/login file calls the module.

#%PAM-1.0

auth requiredpam_securetty.so

auth requiredpam_stack.so service=system-auth

auth requiredpam_nologin.so

account requiredpam_stack.so service=system-auth

password requiredpam_stack.so service=system-auth

# pam_selinux.so close should be the first session rule

session requiredpam_selinux.so close

session requiredpam_stack.so service=system-auth

session optionalpam_console.so

# pam_selinux.so open should be the last session rule

session requiredpam_selinux.so multiple open

pam_securetty modules checks the /etc/securetty file, which terminal are available to root. If terminal is not available in this file then pam_securetty module deny to login on unavailable terminal to root user.

Do the following steps as:

1.vi /etc/named.conf

acl localnet { 192.168.0.0/24; };

options {

allow-query { localnet; };

};

2.service named restart | start

allow-query is a global option on /etc/named.conf, specifies an address match list of hosts allowed to query this server. If this option is not set, any host can query the server.

Do the following steps as:

1.chmod g+s /archive

2.Verify using: ls -ld /archive

Permission should be like:

drwxrws--- 2 root sysuser 4096 Mar 16 18:08 /archive

If SGID bit is set on directory then who every users creates the files on directory group owner automatically the owner of parent directory.

To set the SGID bit: chmod g+s directory

To Remove the SGID bit: chmod g-s directory

By default user1 can remove user2’s files due to directory permission to group member. We can prevent of deleting files from others users using Sticky Bits.

chmod o+t /data

Verify /data: ls -ld /data

You will get: drwxrwx—T

Do the following steps as:

1.vi /etc/cron.allow

root

or

vi /etc/cron.deny

Write all user name to deny.

/etc/cron.allow, /etc/cron.deny file is used to control users to allow or deny. If /etc/cron.allow file is created only that users are allowed to run cron schedule. Another way to deny to users is /etc/cron.deny write all user name on single line.

Do the following steps as:

1.vi /etc/samba/smb.conf

[global]

netbios name=station?

workgroup = mygroup

server string=Share from Linux Server

security=user

smb passwd file=/etc/samba/smbpasswd

encrypt passwords=yes

[data]

path=/data

writable=yes

public=no

browsable=yes

valid users=user1 user2

2.smbpasswd –a user1

3.smbpasswd –a user2

4.service smb start | restart

5.chkconfig smb on

Samba servers helps to share the data between linux and windows. Configuration file is /etc/samba/smb.conf. There are some pre-defined section, i. globaluse to define the global options, ii. Printersuse to share the printers, iii. homesuse the share the user’s home directory.

Security=uservalidation by samba username and password. May be there are other users also. To allow certain share to certain user we should use valid users option.

smbpasswdHelps to change user’s smb password. –a option specifies that the username following should be added to the local smbpasswd file.

Do the following steps as:

1.vi /etc/hosts.deny

vsftpd:ALL EXCEPT .example.com

or

1.vi /etc/hosts.deny

vsftpd:ALL

2.vi /etc/hosts.allow

vsftpd:.example.com

We can secure the services using tcp_wrappers. There are main two files, /etc/hosts.allow and /etc/hosts.deny.

There will be three stage access checking

- Is access explicitly permitted? Means permitted from /etc/hosts.allow?

- Otherwise, Is access explicitly denied? Means denied from /etc/hosts.deny?

- Otherwise, by default permit access if neither condition matched.

To deny the services we can configure /etc/hosts.deny file using ALL and EXCEPT operation. Pattern of /etc/hosts.allow and /etc/hosts.deny file is:

Demon_list:client_list:options

In Client list can be either domain name or IP address.

Do the following steps as:

usermod -G training user1

usermod -G training user2

usermod -G training user3

Verify from : cat /etc/group

There are two types of group, I) primary group II) Secondary or supplementary group.

Primary Group: Primary group defines the files/directories and process owner group there can be only one primary group of one user.

Secondary Group is used for permission. Where permission are defined for group members, user can access by belonging to that group.

Here user1, user2 and user3 belong as supplementary to training group. So these users get the permission of group member.

Do the following steps as:

1.chmod 770 /storage

2.Verify using : ls –ld /storage

Preview should be like:

drwxrwx--- 2 root sysusers 4096 Mar 16 18:08 /storage

To change the permission on directory we use the chmod command. According to the question that only the owner user (root) and group member (sysusers) can fully access the directory so: chmod 770 /archive

Do the following steps as:

1.rpm –ivh ftp://server1.example.com/pub/zsh-*

2.Package will install

rpm command is used to install, update and remove the package, -i means install, -v means verbose and -h means display the hash mark.

Do the following steps as:

1.chgrp sysusers /storage

2.Verify using ls -ld /storage command. You should get like

drwxr-x--- 2 root sysusers 4096 Mar 16 17:59 /storage

chgrp command is used to change the group ownership of particular files or directory.

Another way you can use the chown command.

chown root:sysusers /storage

Do the following steps as:

1.useradd eric

Very tricky question given to you that this user should not belongs to sysadmin group.

Do the following steps as:

1. Insert the CD on CD-ROM and start the system.

2. In Boot: Prompt typelinux askmethod

3. It will display the language, keyboard selection.

4. It will ask you for the installation method.

5. Select the NFS Image from the list

6. It will ask the IP Address, Net mask, Gateway and Name Server. Select Use

Dynamic IP Configuration: because DHCP Server will be configured in your exam lab.

7. It will ask for the NFS Server Name and Redhat Enterprise Linux Directory.

Specify the NFS Server: 172.24.254.254

Directory: /var/ftp/pub

8. After Connecting to the NFS Server Installation start in GUI. Go up to the partition screen by selecting the different Options.

9. Create the partition According to the Question because Size and what-what partition should you create at installation time is specified in your question

10.Create the two RAID partitions having equal size of remaining all free space.

11.Click on RAID button

12.Type mount point /archive

13.Select RAID Level 0

14.Click on ok

15. Then select the MBR Options, time zone and go upto package selections.

It is another Most Important Time of installation. Due to the time limit, you should care about the installation packages. At Exam time you these packages are enough.

X-Window System

GNOME Desktop

(these two packages are generally not required)

Administration Tools.

System Tools

Windows File Server

FTP Servers

Mail Servers

Web Servers

Network Servers

Editors

Text Based Internet

Server Configuration Tools

Printing Supports

When installation will complete, your system will reboot. Jump for another Question.

Steps of Creating LVM:

Physical Disk1

Physical Disk2

Physical Disk3

Physical Volume

Volume Group

Logical Volume 1

Logical Volume 2

Logical Volume 3

1.pvcreate /dev/hda8 /dev/hda9 /dev/hda10

pvdisplay command is used to display the information of physical volume.

2.vgceate test0 /dev/hda8 /dev/hda9 /dev/hda10

vgdisplay command is used to display the information of Volume Group.

3.lvcreate –L 250M –n testvolume1 test0

lvdisplay command is used to display the information of Logical Volume.

4.lvcreate –L 250M –n testvolume2 test0

5.mkfs –t ext3 /dev/test0/testvolume1

6.mkfs –t ext3 /dev/test0/testvolume2

7.mkdir /lvtest1

8.mkdir /lvtest2

9.mount /dev/test0/testvolume1 /lvtest1

10.mount /dev/test0/testvolume2 /lvtest2

11.vi /etc/fstab

/dev/test0/testvolume2/lvtest2ext3defaults0 0

/dev/test0/testvolume1/lvtest1ext3defaults0 0

To create the LVM( Logical Volume Manager) we required the disks having ‘8e’ Linux LVM type. First we should create the physical Volume, then we can create the Volume group from disks belongs to physical Volume. lvcreate command is used to create the logical volume on volume group. We can specify the size of logical volume with –L option and name with -n option.

Do the following steps as:

useradd username

passwd username

usermod -e “date”

example: usermod -e “12 Feb 2006” user4

Verify: chage –l user4

Do the following steps as:

1.usermod -G sysusers jeff

2.usermod –G sysuser marion

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 butuser 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.groupadd sysuser

groupadd command is used to create the group and all group information is stored in /etc/group file.

Do the following steps as:

1.vi /etc/mail/local-host-names

example.com

2.vi /etc/mail/sendmail.mc

dnl # DEAMON_OPTIONS(`Port=smtp,Addr=127.0.0.1,Name=MTA`)dnl

3.m4 /etc/mail/sendmail.mc >/etc/mail/sendmail.cf

4.vi /etc/mail/access

RELAY

example.comRELAY

5.service sendmail start | restart

6.chkconfig dovecot on

7.vi /etc/dovecot.conf

protocols = pop3 pop3s

8.service dovecot start | restart

9.chkconfig dovecot on

/etc/mail/local-host-names file contains the aliases to hostname. Mail server program reads the /etc/mail/sendmail.cf. To change the configuration on mail server, we should edit the /etc/mail/sendmail.mc file and should generate the sendmail.cf using m4 command.

By default sendmail server allows to connect to local host only. So we should edit the /etc/mail/sendmail.mc file to allow connect to other hosts.

By default sendmail server will not forward mail. we should specify on /etc/mail/access to relay or to block mail coming from domain or network or individual email address.

By default dovecot service start only the imap protocol. To start pop protocol with dovecot, we should write in /etc/dovecot.conf file.

Do the following steps as:

1.vi /etc/hosts.deny

ALL:.cracker.org EXCEPT trusted.cracker.org

We can secure the services using tcp_wrappers. There are main two files, /etc/hosts.allow and /etc/hosts.deny.

There will be three stage access checking

-Is access explicitly permitted? Means permitted from /etc/hosts.allow?

- Otherwise, Is access explicitly denied? Means denied from /etc/hosts.deny?

- Otherwise, by default permit access if neither condition matched.

To deny the services we can configure /etc/hosts.deny file using ALL and EXCEPT operation. Pattern of /etc/hosts.allow and /etc/hosts.deny file is:

Demon_list:client_list:options

In Client list can be either domain name or IP address.

Do the following steps as:

1.vi /etc/dhcpd.conf

ddns-update-style none;

option routers 192.168.0.1;

option domain-name “example.com”;

option domain-name-servers 192.168.0.254;

default-lease-time 21600;

max-lease-time 43200;

subnet 192.168.0.0 netmask 255.255.255.0

{

range 192.168.0.10 192.168.0.50;

}

/etc/dhcpd.conf file is used to configure the DHCP. Some global options i.e Gateway, domainname, DNS server specified using option keyword.

service dhcpd start | restart

Do the following steps as:

1.vi /etc/named.conf

zone “example.com” IN {

type master;

file “example.com.zone”;

};

/etc/named.conf file is used to register the zone as well as specify the global option for DNS. There are two types of zone, i. Master, which contains the original data. ii. Slave, backup of master. Here master zone is configured and file name is specified “example.com.zone”, which should be created in /var/named/chroot/var/named/

2.vi /var/named/chroot/var/named/example.com.zone

$TTL 345345

@ IN SOA @ webmaster.example.com.(

101;Serial Number

1H;Refresh Time

1M;Retry Time

1W;Expire Time

1D;Minimum Time to Live

)

@ IN NS 192.100.0.X

www 0 IN A 192.100.0.1

www 0 IN A 192.100.0.2

www 0 IN A 192.100.0.3

www 0 IN A 192.100.0.4

www 0 IN A 192.100.0.5

3.service named start

4.rndc reload

5.chkconfig named on

Zone file should create on /var/named/chroot/var/named. Default Directory Path is specified on /var/named.conf.

$TTLTime To Live, How much seconds cache server stores the information about DNS. And Five Parameters specified Serial Number used by slave to synchronize with master server. Refresh and Retry Time used by slave server. NS is the Name (DNS) server where lookup the domain. A (Associated IP) for particular host. DNS has mechanism to load balance the request from clients. You can verify using hostwww.example.com command.

Do the following steps as:

1.vi /etc/aliases

john:jane

2.newaliases

We can redirect the mail of one user to another user using /etc/aliases file. In example all mail of john goes to jane user. When you configure this line mail automatically goes to jane’s mail spooling directory.

Do the following steps as:

1.Verify the File whether Shared or not ? : cat /etc/exports

2.Start the nfs service: service nfs start

3.Start the portmap service: service portmap start

4.Make automatically start the nfs service on next reboot: chkconfig nfs on

5.Make automatically start the portmap service on next reboot: chkconfig portmap on

6.Verify either sharing or not: showmount –e localhost

7.Check that default firewall is running on system ? if running flush the iptables using iptables –F and stop the iptables service.

#vi /etc/resolv.conf

nameserver 172.24.254.254

# dig server1.example.com

#host server1.example.com

DNS is the Domain Name System, which maintains a database that can help your computer translate domain names such as www.redhat.com to IP addresses such as 216.148.218.197. As no individual DNS server is large enough to keep a database for the entire Internet, they can refer requests to other DNS servers.

DNS is based on thenameddaemon, which is built on the BIND (Berkeley Internet Name Domain) package developed through the Internet Software Consortium

Users wants to access by name so DNS will interpret the name into ip address. You need to specify the Address if DNS server in each and every client machine. In Redhat Enterprise Linux, you need to specify the DNS server into /etc/resolv.conf file.

After Specifying the DNS server address, you can verify using host, dig and nslookup commands.

Maintenance mode also known as emergency mode. System boots on emergency mode when file system error occurred. It is due to unknown partition, bad filesystem specified in /etc/fstab. To slove follow the steps

Give the Root password

fdisk –lVerify the Number of parations.

Identify the Root partition, e2label /dev/hda1, e2label /dev/hda2…..

Remount the root partation on rw mode: mount –o remount,defaults /dev/hda6 /

vi /etc/fstab

Correct all partitions, mount point, mount options, file system etc.

6.Press ctrl+d

Do the following steps as:

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

Type nFor New partitions

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.

Press w to write on partitions table.

Either Reboot or use partprobe command.

Use mkfs –t ext3 /dev/hda?

Or

mke2fs –j /dev/hda? To create ext3 filesystem.

vi /etc/fstab

Write:

/dev/hda?/dataext3defaults1 2

11. Verify by mounting on current Sessions also:

mount /dev/hda? /data

Do the following steps as:

vi /etc/resolv.conf

nameserver 172.24.254.254

host server1.example.com

Do the following steps as:

vi /etc/sysconfig/network-scripts/ifcfg-eth0

DEVICE=eth0

BOOTPROTO=static

ONBOOT=yes

IPADDR=x.x.x.x

NETMASK=x.x.x.x

Enter the IP Address as given station number by your examiner: example: 172.24.0.1

Enter Subnet Mask

Enter Default Gateway and primary name server

press on ok

ifdown eth0

ifup eth0

verify using ifconfig

In the lab server is playing the role of router, IP forwarding is enabled. Just set the Correct IP and gateway, you can ping to 172.25.254.254.

1. vi /etc/resolv.conf

Write : nameserver 192.168.0.254

Do the following steps as:

1.First check the size of Logical Volume: lvdisplay /dev/vo/myvol

2.Increase the Size of Logical Volume: lvextend -L+121M /dev/vo/myvol

3.Make Available the size on online: resize2fs /dev/vo/myvol

4.Verify the Size of Logical Volume: lvdisplay /dev/vo/myvol

5.Verify that the size comes in online or not: df -h

We can extend the size of logical Volume using the lvextend command. As well as to decrease the size of Logical Volume, use the lvresize command. In LVM v2 we can extend the size of Logical Volume without unmount as well as we can bring the actual size of Logical Volume on online using ext2online command.

Do the following steps as:

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

Type nFor New partitions

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.

Press w to write on partitions table.

Either Reboot or use partprobe command.

Use mkfs –t ext3 /dev/hda? Where ? is your partition number

Or

mke2fs –j /dev/hda? To create ext3 filesystem.

mkdir /mnt/neo

vi /etc/fstab

Write:

/dev/hda?/mnt/neoext3defaults1 2

Verify by mounting on current Sessions also:

mount /dev/hda? /mnt/neo

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`

Very Tricky question from redhat. Actually question is giving scenario to you to implement quota to neo user. You should apply the quota to neo user on /home that neo user shouldn’t occupied space more than 70K.

1.vi /etc/fstab

LABEL=/home/homeext3defaults,usrquota0 0To enable the quota on filesystem you should mount the filesystem with usrquota for user quota and grpquota for group quota.

2.touch /home/aquota.userCreating blank quota database file.

3.mount -o remount /homeRemounting the /home with updated mount options. You can verify that /home is mounted with usrquota options or not using mount command.

4.quotacheck -u /homeInitialization the quota on /home

5.edquota –u neo /homeQuota Policy editor

See the snapshot

Disk quotas for user neo (uid 500):

Filesystem blocks soft hard inodes soft hard

/dev/mapper/vo-myvol 2 30 70 1 0 0

Can you set the hard limit 70 and soft limit as you think like 30.

Verify using the repquota /home command.

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

Quotas are used to limit a user's or a group of users' ability to consume disk space. This prevents a small group of users from monopolizing disk capacity and potentially interfering with other users or the entire system. Disk quotas are commonly used by ISPs, by Web hosting companies, on FTP sites, and on corporate file servers to ensure continued availability of their systems.

Without quotas, one or more users can upload files on an FTP server to the point of filling a filesystem. Once the affected partition is full, other users are effectively denied upload access to the disk. This is also a reason to mount different filesystem directories on different partitions. For example, if you only had partitions for your root (/) directory and swap space, someone uploading to your computer could fill up all of the space in your root directory (/). Without at least a little free space in the root directory (/), your system could become unstable or even crash.

You have two ways to set quotas for users. You can limit users by inodes or by kilobyte-sized disk blocks. Every Linux file requires an inode. Therefore, you can limit users by the number of files or by absolute space. You can set up different quotas for different filesystems. For example, you can set different quotas for users on the /home and /tmp directories if they are mounted on their own partitions.

Limits on disk blocks restrict the amount of disk space available to a user on your system. Older versions of Red Hat Linux included LinuxConf, which included a graphical tool to configure quotas. As of this writing, Red Hat no longer has a graphical quota configuration tool. Today, you can configure quotas on RHEL only through the command line interface.

1. vi /etc/fstab

/dev/hda11/dataext3defaults,usrquota 1 2

2. Either Reboot the System or remount the partition.

Mount –o remount /dev/hda11 /data

3. touch /data/aquota.user

4. quotacheck –ufm /data

5. quotaon -u /data

6. edquota –u user1 /data

and Specified the Soft limit and hard limit on opened file.

To verify either quota is working or not:

Soft limit specify the limit to generate warnings to users and hard limit can’t cross by the user. Use the quota command or repquota command to monitor the quota information.

Do the following steps as:

echo “1” >/proc/sys/net/ipv4/ip_forward

vi /etc/sysctl.conf

net.ipv4.ip_forward=1

/proc is the virtual filesystem, containing the information about the running kernel. To change the parameter of running kernel you should modify on /proc. From Next reboot the system, kernel will take the value from /etc/sysctl.conf.

Do the following steps as:

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

Type nFor New partitions

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.

Press w to write on partitions table.

Either Reboot or use partprobe command.

Use mkfs –t ext3 /dev/hda?

Or

mke2fs –j /dev/hda? To create ext3 filesystem.

vi /etc/fstab

Write:

/dev/hda?/dataext3defaults0 0

Verify by mounting on current Sessions also:

mount /dev/hda? /data

Do the following steps as:

1.First check the size of Logical Volume: lvdisplay /dev/vo/myvol

2.Make sure that the filesystem is in a consistent state before reducing:

# fsck –f /dev/vo/myvol

3.Now reduce the filesystem by 200MB.

# resize2fs /dev/vo/myvol 200M

4.It is now possible to reduce the logical volume.

#lvreduce /dev/vo/myvol –L 200M

4.Verify the Size of Logical Volume: lvdisplay /dev/vo/myvol

5.Verify that the size comes in online or not: df -h

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:

1.useradd jeff

2.useradd marion

3.useradd harold

useradd command is used to create the user. All user’s information stores in /etc/passwd and user;s shadow password stores in /etc/shadow.

Do the following steps as:

1.useradd jane

2.useradd john

useradd command is used to create the user. All user’s information stores in /etc/passwd and user;s shadow password stores in /etc/shadow.

Do the following steps as:

Login as a root user

cat >schedule.txt

30 05 * * * /bin/echo “Hello”

3. crontab –u jeff schedule.txt

4. service crond restart

The cron system is essentially a smart alarm clock. When the alarm sounds, Linux runs the commands of your choice automatically. You can set the alarm clock to run at all sorts of regular time intervals. Alternatively, the at system allows you to run the command of your choice once, at a specified time in the future.

Red Hat configured the cron daemon, crond. By default, it checks a series of directories for jobs to run, every minute of every hour of every day. The crond checks the /var/spool/cron directory for jobs by user. It also checks for scheduled jobs for the computer under /etc/crontab and in the /etc/cron.d directory.

Here is the format of a line in crontab. Each of these columns is explained in more detail:

#minute, hour, day of month, month, day of week, command

*        *     *             *      *            command

Entries in a crontab Command Line

Field

Value

Minute

0-59

Hour

Based on a 24-hour clock; for example, 23 = 11 p.m.

Day of month

1-31

Month

1-12, or jan, feb, mar, etc.

Day of week

0-7; where 0 and 7 are both Sunday; or sun, mon, tue, etc.

Command

The command you want to run

Do the following steps as:

useradd user1

useradd user2

useradd user3

passwd user1

passwd user2

passwd user3

We create the user using useradd command and we change the password of user using passwd command. If you want to set the blank password use: passwd -d username.

Do the following steps as:

1. Insert the CD on CD-ROM and start the system.

2. In Boot: Prompt typelinux askmethod

3. It will display the language, keyboard selection.

4. It will ask you for the installation method.

5. Select the NFS Image from the list

6. It will ask the IP Address, Net mask, Gateway and Name Server. Select Use

Dynamic IP Configuration: because DHCP Server will be configured in your exam lab.

7. It will ask for the NFS Server Name and Redhat Enterprise Linux Directory.

Specify the NFS Server: 172.24.254.254

Directory: /var/ftp/pub

8. After Connecting to the NFS Server Installation start in GUI. Go up to the partition screen by selecting the different Options.

9. Create the partition According to the Question because Size and what-what partition should you create at installation time is specified in your question

10.Create the two RAID partitions having equal size of remaining all free space.

11.Click on RAID button

12.Type mount point /archive

13.Select RAID Level 0

14.Click on ok

15. Then select the MBR Options, time zone and go upto package selections.

It is another Most Important Time of installation. Due to the time limit, you should care about the installation packages. At Exam time you these packages are enough.

X-Window System

GNOME Desktop

(these two packages are generally not required)

Administration Tools.

System Tools

Windows File Server

FTP Servers

Mail Servers

Web Servers

Network Servers

Editors

Text Based Internet

Server Configuration Tools

Printing Supports

When installation will complete, your system will reboot. Jump for another Question.

Note: Examiner will provide you the Installation startup CD. And here mentioned size may vary see on the exam paper.

1.Insert the CD on CD-ROM and start the system.

2.In Boot: Prompt typelinux askmethod

3. It will display the Language, keyboard selection.

4. It will ask you for the installation method.

5. Select the FTP from the list

6. It will ask the IP Address, Net mask, Gateway and Name Server. Select Use

Dynamic IP Configuration: because DHCP Server will be configured in your exam lab.

7. It will ask for the FTP site name and Redhat Enterprise Linux Directory.

Specify the FTP Server: 192.168.0.254

Directory: pubBecause anonymous login on /var/ftp.

8. After Connecting to the FTP Server Installation will start. Go up to the partition screen by selecting the different Options.

9. Create the partition According to the Question because Size and what-what partition should you create at installation time is specified in your question

10. Then select the MBR Options, time zone and go upto package selections.

It is another Most Important Time of installation. Due to the time limit, you should be

care about the installation packages. At Exam time you these packages are enough.

X-Window System

GNOME Desktop

(these two packages are generally not required)

Administration Tools.

System Tools

Windows File Server

FTP Servers

Mail Servers

Web Servers

Network Servers

Editors

Text Based Internet

Server Configuration Tools

Printing Supports

When installation will complete, your system will reboot. Jump for another Question.

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.

IPP( Internet Printing Protocol), allows administrator to manage printer through browser so CUPS is called Internet Printing Protocol based on HTTP. We can Install the printer either through: system-confing-printer tool or through Browser.

1.Open the browser and Type on address: http://localhost:631CUPS (Common Unix Printing System) used the IPP protocol. CUPS use the 631 port.

2.Click on Manage Printer.

3.Click on Add Printer.

4.Type Printer name, Location, Description.

5.Select Device for bb. (Select IPP).

6.Device URL: ipp://192.168.0.254/ipp/ queue nameSame printer name of shared printer.

7.Select Model/Driver RAW printer.

8.service cups restart

Do the following steps as:

1.chmod 770 /archive

2.Verify using : ls –ld /archive

Preview should be like:

drwxrwx--- 2 root sysuser 4096 Mar 16 18:08 /archive

To change the permission on directory we use the chmod command. According to the question that only the owner user (root) and group member (sysuser) can fully access the directory so: chmod 770 /archive

Do the following steps as:

1.iptables -t nat -A POSTROUTING -s 192.168.0.0/24 -p tcp -j SNAT –to-source 202.2.2.2.

POSTROUTINGThis filter point handles packets immediately prior leaving the system.

When Packets leave the system all’s source address change to 202.2.2.2 and can access the internet.

iptables is the build-in firewall tools, used to filter the packets and for nat. By identifying Source Address, Destination Address, type of protocol, source and destination port we can filter the packets.

-sSource Address

-dDestination Address

-pLayer 3 Protocol

-dDestination Address

--sportSource Prot

--dportDestination Port

-iIncoming Interface

-oOutgoing Interface

-tTable either filter or nat or mangle

-AChain can be either INPUT, OUTPUT, FORWARD, PREROUTING, POSTROUTING.

Do the following steps as:

1.vi /etc/httpd/conf/httpd.conf

ServerNamewww.abc.com

DocumentRoot /var/www/abc/

AllowOverrideauthconfig

DirectoryIndexindex.html

ServerAdminwebmaster@abc.com

ErrorLog logs/error_abc.logs

CustomLog logs/custom_abc.logs common

2.Create the directory and index page on specified path. (Index page can download fromftp://server1.example.comat exam time)

Check the SELinux context of index.html file, should be like this:

-rw-r--r-- root root system_u:object_r:httpd_sys_content_t /var/www/html/index.html

If SELinux Context is mismatched, use the restorecon –R /var command

3.vi /var/www/abc/.htaccess

AuthName“Only to Authorized Users”

AuthTypebasic

AuthUserFile/etc/httpd/conf/mypasswd

requirevalid-user

Check the SELinux Context, should like this:

-rw-r--r-- root root root:object_r:httpd_sys_content_t .htaccess

htpasswd –c /etc/httpd/conf/mypasswd user5

htpasswd –m /etc/httpd/conf/mypasswd user6

chgrp apache /etc/httpd/conf/mypasswd

chmod g+r /etc/httpd/conf/mypasswd

Check the SELinux Context, should like this:

-rw-r--r-- root root system_u:object_r:httpd_config_t /etc/httpd/conf/mypasswd

Use restorecon command to restore the mismatched SELinux Context of the file.

service httpd restart

chkconfig httpd on

AllowOverride Authconfig is used to specify which and how much configuration can be overridden by directory specific .htaccess files.

One of the most common tasks performed in users’ .htaccess files is adding authorization. Typically, a user will setup authorization for directories that hold sensitive information with a configuration.

Do the following steps as:

1.vi /etc/hosts.deny

vsftpd:ALL EXCEPT .example.com

or

1.vi /etc/hosts.deny

vsftpd:ALL

2.vi /etc/hosts.allow

vsftpd:.example.com

We can secure the services using tcp_wrappers. There are main two files, /etc/hosts.allow and /etc/hosts.deny.

There will be three stage access checking

- Is access explicitly permitted? Means permitted from /etc/hosts.allow?

- Otherwise, Is access explicitly denied? Means denied from /etc/hosts.deny?

- Otherwise, by default permit access if neither condition matched.

To deny the services we can configure /etc/hosts.deny file using ALL and EXCEPT operation. Pattern of /etc/hosts.allow and /etc/hosts.deny file is:

Demon_list:client_list:options

In Client list can be either domain name or IP address.

Here your Local LAN means your domain named example.com.

1.vi /etc/mail/local-host-names

example.com

2.vi /etc/mail/sendmail.mc

dnl # DEAMON_OPTIONS(`Port=smtp,Addr=127.0.0.1,Name=MTA`)dnl

3.m4 /etc/mail/sendmail.mc >/etc/mail/sendmail.cf

4.vi /etc/mail/access

192.168.0RELAY

5.service sendmail start | restart

6.chkconfig sendmail on

/etc/mail/local-host-names file contains the aliases to hostname. Mail server program reads the /etc/mail/sendmail.cf. To change the configuration on mail server, we should edit the /etc/mail/sendmail.mc file and should generate the sendmail.cf using m4 command.

By default sendmail server allows to connect to local host only. So we should edit the /etc/mail/sendmail.mc file to allow connect to other hosts.

By default sendmail server will not forward mail. we should specify on /etc/mail/access to relay or to block mail coming from domain or network or individual email address.

7.vi /etc/aliases

john:jane

8.newaliases

We can redirect the mail of one user to another user using /etc/aliases file. In example all mail of john goes to jane user.

Do the following steps as:

1.vi /etc/security/time.conf

login;*;user9|user10;SuMoFri1200-1400

2.vi /etc/pam.d/login

accountrequiredpam_time.so

For Time based authentication, we should configured in /etc/security/time.conf

Syntax of /etc/security/time.conf

services;ttys;users;times

services

is a logic list of PAM service names that the rule applies to.

ttys

is a logic list of terminal names that this rule applies to.

users

is a logic list of users to whom this rule applies.

times

the format here is a logic list of day/time-range entries the days are specified by a sequence of two character entries, MoTuSa for example is Monday Tuesday and Saturday. Note that repeated days are unset MoMo = no day, and MoWk = all weekdays bar Monday. The two character combinations accepted are

Mo Tu We Th Fr Sa Su Wk Wd Al

the last two being week-end days and all 7 days of the week respectively. As a final example, AlFr means all days except Friday.

pam_time modules checks the file /etc/security/time.conf for authentication. So, we should call the pam_time modules in /etc/pam.d/login.

Do the following steps as:

1.vi /etc/samba/smb.conf

[global]

netbios name=station?

workgroup=linuxgroup

security=share

printcap name=/etc/printcap

load printers=yes

printing=cups

[printers]

path=/var/spool/samba

browsable=yes

printable=yes

guest ok=no

writable=no

Samba servers helps to share the data between linux and windows. Configuration file is /etc/samba/smb.conf. There are some pre-defined section, i. globaluse to define the global options, ii. Printersuse to share the printers, iii. homesuse to share the user’s home directory.

/etc/printcap file contains all installed printers name. Printing is print system used on server.

Do the following steps as:

1.vi /etc/security/access.conf

-:john:LOCAL

2.vi /etc/pam.d/system-auth

accountrequired/lib/security/pam_access.so

/etc/security/access.conf file helps to allow or deny login to users on the basis of origin.

Syntax of /etc/security/access.conf

permission : users : origins

The first field should be a "+" (access granted) or "-" (access denied) character.

The second field should be a list of one or more login names, group names, or ALL (always matches). A pattern of the form user@host is matched when the login name matches the "user" part, and when the "host" part matches the local machine name.

The third field should be a list of one or more tty names (for non-networked logins), host names, domain names (begin with "."), host addresses, internet network numbers (end with "."), ALL (always matches) or LOCAL (matches any string that does not contain a "." character).

In our example denied to john user to login locally.

At exam Lab example.com domain resides on 172.24.0.0/16 Network and my133t.org resides on 172.25.0.0/16 Network.

1.vi /etc/squid/squid.conf

#detault:

http_port8080

#Recommended minimum configuration:

# Near the src acl src section

acl allownet src 172.24.0.0/255.255.0.0

acl denynet src 172.25.0.0/255.255.0.0

#Default:

# http_access deny all

#Under Herehttp_access allow allownet

http_access deny denynet

2.service squid start

3.chkconfig squid on

squid is a proxy caching server, using squid we can share the internet, block the internet, to certain network. First we should define the port for squid, the standard port for squid is 3128. We can run squid on different port by specifying http_port portnumber.

At exam time read the Lab Scenario carefully. Actually there are two different networks one is 192.168.0.0/24 where your system resides know as example.com domain and another is 192.168.1.0/24 know as cracker.org domain.

One server named sever1.example.com having 192.168.0.254 and 192.168.1.254 is running in your exam. If you make a gateway to that server, you will can ping because IP forwarding is enabled on that server.

1.vi /etc/sysconfing/network

NETWORKING=yes

HOSTNAME=station?.example.com

GATEWAY=192.168.0.254

2.service network restart

Or

1.vi /etc/sysconfig/network-scripts/ifcfg-eth0

DEVICE=eth0

ONBOOT=yes

BOOTPROTO=static

IPADDR=X.X.X.X

NETMASK=X.X.X.X

GATEWAY=192.168.0.254

2.ifdown eth0

3.ifup eth0

Note: If gateway is specified in both file, default gateway takes from interface specific file.

Do the following steps as:

hostname station?.example.comThis will set the host name only for current session. To set hostname permanently.

vi /etc/sysconfig/network

HOSTNAME=station?.example.com

service network restart

1. vi /etc/resolv.conf

Write : nameserver 192.168.0.254

Do the following steps as:

1.Verify the File whether Shared or not ? : cat /etc/exports

2.Start the nfs service: service nfs start

3.Start the portmap service: service portmap start

4.Make automatically start the nfs service on next reboot: chkconfig nfs on

5.Make automatically start the portmap service on next reboot: chkconfig portmap on

6. Check default firewall is running in your system

# service iptables status

#iptables –F

#service iptables stop

#chkconfig iptables off

6.Verify Either sharing or not: showmount –e localhost

You will see that some shared directory will display

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:

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 !

This error occurred in your system before showing welcome redhat linux. That means problem in grub boot loader.

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.

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.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.

Do the following steps as:

1.vi /etc/sysconfig/network

GATEWAY=192.168.0.254

OR

vi /etc/sysconf/network-scripts/ifcfg-eth0

DEVICE=eth0

BOOTPROTO=static

ONBOOT=yes

IPADDR=192.168.0.?

NETMASK=255.255.255.0

GATEWAY=192.168.0.254

2.service network restart

The LVM system organizes hard disks into Logical Volume (LV) groups. Essentially, physical hard disk partitions (or possibly RAID arrays) are set up in a bunch of equal-sized chunks known as Physical Extents (PE). As there are several other concepts associated with the LVM system, let's start with some basic definitions:

Physical Volume (PV)is the standard partition that you add to the LVM mix. Normally, a physical volume is a standard primary or logical partition. It can also be a RAID array.

Physical Extent (PE)is a chunk of disk space. Every PV is divided into a number of equal sized PEs. Every PE in a LV group is the same size. Different LV groups can have different sized PEs.

Logical Extent (LE)is also a chunk of disk space. Every LE is mapped to a specific PE.

Logical Volume (LV)is composed of a group of LEs. You can mount a filesystem such as /home and /var on an LV.

Volume Group (VG)is composed of a group of LVs. It is the organizational group for LVM. Most of the commands that you'll use apply to a specific VG.

1.Verify the size of Logical Volume:lvdisplay /dev/vg0/lv1

2.Verify the Size on mounted directory:df –h or df –h mounted directory name

3.Use :lvextend –L+400M /dev/vg0/lv1

4. ext2online –d /dev/vg0/lv1to bring extended size online.

5. Again Verify using lvdisplay and df –h command.

After completing the Boot loader problem, you will boot the system, but it goes to emergency mode. Remember that if System boots on Emergency mode that means file system problem.

You will get the Shell, remount the / filesystem with read and write mode.

1.First Find out the / filesystem using e2lable /dev/hda1, e2lable /dev/hda2 etc

2.mount –o remount,defaults /dev/hda? /

3.vi /etc/fstab

You will get like:

/root/ext3defaults 1 1

or //rootext3defaults 1 1

4.Edit the file like:

//ext3defaults 1 1

5.Configure the /etc/grub.conf file if just booting system by editing grub from grub prompt.

6.Reboot the system.

Do the following steps as:

Use netconfig command

Enter the IP Address as given station number by your examiner: example: 172.24.0.1

Enter Subnet Mask

Enter Default Gateway and primary name server

press on ok

ifdown eth0

ifup eth0

verify using ifconfig

In the lab server is playing the role of router, IP forwarding is enabled. Just set the Correct IP and gateway, you can ping to 172.25.254.254.

Very Tricky question from redhat. Actually question is giving scenario to you to implement quota to neo user. You should apply the quota to neo user on /home that neo user shouldn’t occupied space more than 70K.

1.vi /etc/fstab

LABEL=/home/homeext3defaults,usrquota0 0To enable the quota on filesystem you should mount the filesystem with usrquota for user quota and grpquota for group quota.

2.touch /home/aquota.userCreating blank quota database file.

3.mount -o remount /homeRemounting the /home with updated mount options. You can verify that /home is mounted with usrquota options or not using mount command.

4.quotacheck -u /homeInitialization the quota on /home

5.edquota –u neo /homeQuota Policy editor

See the snapshot

1 Disk quotas for user neo (uid 500):

2 Filesystem blocks soft hard inodes soft hard

4 /dev/mapper/vo-myvol 2 30 70 1 0 0

Can you set the hard limit 70 and soft limit as you think like 30.

Do the following steps as:

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

Type nFor New partitions

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.

Press w to write on partitions table.

Either Reboot or use partprobe command.

Use mkfs –t ext3 /dev/hda?

Or

mke2fs –j /dev/hda? To create ext3 filesystem.

vi /etc/fstab

Write:

/dev/hda?/dataext3defaults0 0

11. Verify by mounting on current Sessions also:

mount /dev/hda? /data

Do the following steps as:

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

Type nFor New partitions

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.

Press w to write on partitions table.

Either Reboot or use partprobe command.

Use mkfs –t ext3 /dev/hda? Where ? is your partition number

Or

mke2fs –j /dev/hda? To create ext3 filesystem.

mkdir /mnt/neo

vi /etc/fstab

Write:

/dev/hda?/mnt/neoext3defaults1 2

Verify by mounting on current Sessions also:

mount /dev/hda? /mnt/neo

Do the following steps as:

1. use the authconfig or system-config-authentication

2. Select the [*] USE NIS

3. Type the NIS Domain: rhce.com

4. Type Server 192.168.0.254 then click on next and ok

5. You will get a ok message.

6. vi /etc/auto.master and write at the end of file

/home/stationx /etc/auto.home --timeout=60

7. vi /etc/auto.home and write

*-rw,soft,intr192.168.0.254:/home/stationx/&

Note: please specify your station number in the place of x.

8. Service autofs restart

9. Login as the rhce1 or rhce2 or rhce3 on another terminal will be

Success.

According to question, rhce.com domain is already configured. We have to make a client of rhce.com domain and automatically mount the home directory on every client. To make a member of domain, we use the autheconfig or system-config-authentication command. There are lots of authentication server i.e NIS, LDAB, SMB etc. NIS is a RPC related Services, no need to configure the DNS, we should specify the NIS server address.

Here Automount feature is available. When user tried to login, home directory will automatically mount. The automount service reads the configuration from /etc/auto.master file.

On /etc/auto.master file we specified the mount point the configuration file for mount point.

Do the following steps as:

1.echo “1” >/proc/sys/net/ipv4/ip_forward

2.vi /etc/sysctl.conf

net.ipv4.ip_forward = 1

If you want to use the Linux System as a Router to make communication between different networks, you need enable the IP forwarding. To enable on running session just set value 1 to /proc/sys/net/ipv4/ip_forward. As well as automatically turn on the IP forwarding features on next boot set on /etc/sysctl.conf file.

Note: Examiner will provide you the Installation startup CD. And here mentioned size may vary see on the exam paper.

1.Insert the CD on CD-ROM and start the system.

2.In Boot: Prompt typelinux askmethod

3. It will display the Language, keyboard selection.

4. It will ask you for the installation method.

5. Select the HTTP from the list

6. It will ask the IP Address, Net mask, Gateway and Name Server. Select Use

Dynamic IP Configuration: because DHCP Server will be configured in your exam lab.

7. It will ask for the Web site name and Redhat Enterprise Linux Directory.

Specify the HTTP Server: 192.168.0.254

Directory: rhel4Because Default Directory for http is /var/www/html

8. After Connecting to the HTTP Server Installation start. Go upto the partition screen by selecting the different Options.

9. Create the partition According to the Question because Size and what-what partition should you create at installation time is specified in your question

10. Then select the MBR Options, time zone and go upto package selections.

It is another Most Important Time of installation. Due to the time limit, you should be

care about the installation packages. At Exam time you these packages are enough.

X-Window System

GNOME Desktop

(these two packages are generally not required)

Administration Tools.

System Tools

Windows File Server

FTP Servers

Mail Servers

Web Servers

Network Servers

Editors

Text Based Internet

Server Configuration Tools

Printing Supports

When installation will complete, your system will reboot. Jump for another Question.

We can change the permission of file/directory either character symbol method or numeric method.

Permission:

r-Read

w-Write

x-Execute

Permission Category

u- Owner User

g- Owner Group

o- Others

Operators

+Add the Permissions

-Remove the Permissions

=Assigns the Permissions

Numeric Method:

4Read

2Write

1Execute

Total: 7, total for owner user, owner group member and for others : 777

chmod u+rwx /data

chmod g+rwx /data

chmod o-rwx /data

or

chmod 770 /data

Verify the /data : ls –ld /data

You will get drwxrwx---

Do the following steps as:

1.chmod g+s /data

2.Verify using: ls -ld /data

Permission should be like:

drwxrws--- 2 root sysadmin 4096 Mar 16 18:08 /data

If SGID bit is set on directory then who every users creates the files on directory group owner automatically the owner of parent directory.

To set the SGID bit: chmod g+s directory

To Remove the SGID bit: chmod g-s directory

Do the following steps as:

rpm -ivh ftp://server1.example.com/pub/kernel-hugemem-*

2. vi /etc/grub.conf

Set the default to new kernel

default=0

Example of /etc/grub.conf

default=0

timeout=5

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

hiddenmenu

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

root (hd0,0)

kernel /vmlinuz-2.6.9-5.ELhugemem ro root=LABEL=/1 rhgb quiet

initrd /initrd-2.6.9-5.ELhugemem.img

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

root (hd0,0)

kernel /vmlinuz-2.6.9-5.EL ro root=LABEL=/1 rhgb quiet

initrd /initrd-2.6.9-5.EL.img

rpm command is used to install, update and remove the rpm package. -ivh option is install, verbose, and display the hash mark.

Do the following steps as:

useradd username

passwd username

usermod -e “date”

example: usermod -e “12 Feb 2006” user4

Verify: chage –l user4

Redhat Enterprise Linux 5 Supports the RAID LEVEL 0, RAID LEVEL 1, RAID LEVEL 5 and RAID LEVEL 6 at installation time. You can create it at installation time later no need to type lots of commands for RAID.

At Installation Time:

Create the partitions using diskdruid.

Create the Partitions having File system Type Software RAID.

Click on RAID button

Type the Mount Point

Select File system type

Select RAID Level

Select Partitions/disks as a member of RAID.

viii.Click on ok

After Installation: We can create the RAID Device after Installation on command-line.

Create the Two partitions having equal size. (Specify the Size using Cylinder, find the remaining cylinder and divide by 2).

Change the Partition ID to fd (Linux raid Autodetect) by typing t.

Type wTo write on partitions table.

Use partprobe command to synchronic the partition table.

Use: mdadm --create /dev/md0 --level=1 --raid-devices=2 /dev/hda? /dev/hda?

Verify the RAID: mdadm --detail /dev/md0

mkfs -t ext3 /dev/md0

mount /dev/md0 /data

vi /etc/fstab

/dev/md0/dataext3defaults0 0

Verify mounting devices using mount command.