Q101. CORRECT TEXT
One Logical Volume is created named as myvol under vo volume group and is mounted. The Initial Size of that Logical Volume is 124MB. Make successfully that the size of Logical Volume 245MB without losing any data. The size of logical volume 240MB to 255MB will be acceptable.
Answer and Explanation:
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.
Q102. CORRECT TEXT
Deny the ALL services to the member of cracker.org but allow to trusted.cracker.org.
Answer and Explanation:
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.
Q103. CORRECT TEXT
Configure to deny the pop and imap connection from outside local LAN as well as station20.example.com.
Answer and Explanation:
1. vi /etc/hosts.deny
dovecot:ALL EXCEPT .example.com EXCEPT station20.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.
Q104. CORRECT TEXT
Install the Redhat Linux RHEL 4 through NFS. Where your Server is server1.example.com having IP 172.24.254.254 and shared /var/ftp/pub. The size of the partitions are listed below:
/ à 1048
/home à 1028
/boot à 512
/var à 1028
/usr à 2048
Swap -> 1.5 of RAM Size
/archive à configure the RAID Level 0 of remaining all free space.
After completing the installation through NFS solve the following questions. There are two networks 172.24.0.0/16 and 172.25.0.0/16. As well as there are two domains example.com on 172.24.0.0/16 network and my133t.org on 172.25.0.0/16 network. Your system is based on example.com domain.
Answer and Explanation:
1. Insert the CD on CD-ROM and start the system.
2. In Boot: Prompt type linux 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.
Q105. CORRECT TEXT
Successfully resolv to server1.example.com where your DNS server is 172.24.254.254
Answer and Explanation:
1. vi /etc/resolv.conf
nameserver 172.24.254.254
2. host server1.example.com
On every clients, DNS server is specified in /etc/resolv.conf. When you request by name it tries to resolve from DNS server.
Q106. CORRECT TEXT
There are mixed lots of System running on Linux and Windows OS. Some users are working on Windows Operating System. There is a /data directory on linux server should make available on windows to user1 and user2 users on read and write mode and read only to other samba users.
Answer and Explanation:
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=no
public=no
browsable=yes
write list= 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 à use to define the global options, ii. Printers à use to share the printers, iii. homes à use the share the user's home directory.
Security=user à 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 à Helps to change user's smb password. -a option specifies that the username following should be added to the local smbpasswd file.
If any valid users option is not specified, then all samba users can access the shared data. By Default shared permission is on writable=no means read only sharing. Write list option is used to allow write access on shared directory to certain users or group members.
Q107. CORRECT TEXT
Now a days you are observing that your system being very slow. You observe the processes that one user named user1 running more than 50 processes. Configure to limit the number of processes that user1 couldn't run more than 7 process.
Answer and Explanation:
1. vi /etc/security/limits.conf
user1 hard nproc 7
2. vi /etc/pam.d/system-auth
session required /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.
Q108. CORRECT TEXT
You are new System Administrator and from now you are going to handle the system and your main task is Network monitoring, Backup and Restore. But you don't know the root password.
Change the root password to redhat and login in default Runlevel.
Answer and Explanation:
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.
1. Restart the System.
2. You will get the boot loader GRUB screen.
3. Press a and type 1 or s for single mode
ro root=LABEL=/ rhgb queit s
4. System will boot on Single User mode.
5. Use passwd command to change.
6. Press ctrl+d
Q109. CORRECT TEXT
Share the Internet using squid for your Local LAN. Proxy server should be run on 8080 port.
Answer and Explanation:
1. vi /etc/squid/squid.conf
#detault:
http_port 8080
#Recommended minimum configuration:
# Near the src acl src section
acl mynet src 192.168.0.0/255.255.255.0
#Default:
# http_access deny all
#Under Here
http_access allow mynet
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.
To block or allow the Internet access to hosts, we should create the acl (Access Control List). In this file we can specify only the IP address.
Example: acl aclname src IP/Netmask
After creating acl we can block or allow the internet to specified acl.
http_access allow | deny alcname
Q110. CORRECT TEXT
Boot your System Successfully on runlevel 3.
Answer and Explanation:
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.