Deny to all users except root to run cron schedule.
Answer and Explanation:
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.
Install the Redhat Linux RHEL 5 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:
/1048
/home1028
/boot 512
/var 1028
/usr2048
Swap->1.5 of RAM Size
/documentconfigure 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 cracker.org on 172.25.0.0/16 network. Your system is based on example.com domain. SELinux Must be on enforcing mode.
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 /document
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.
You are working as a System Administrator at Certpaper. Your Linux Server crashed and you lost every data. But you had taken the full backup of user’s home directory and other System Files on /dev/st0, how will you restore from that device?
Answer and Explanation:
1. Go to on that directory where you want to restore.
2. restore –rf /dev/st0
To restore from backup we use the restore command. Here backup will restore from /dev/st0 on current Directory.
Create the user named user1, user2, user3
Answer and Explanation:
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.
Install the dialog-*
Answer and Explanation:
Questions asking you to install the dialog package from the server. In your Lab FTP server as well as NFS server are configured. You can install either through FTP or NFS.
1.Just Login to server1.example.com through FTP: ftp server1.example.com
2.Enter to pub directory: cd pub
3.Enter to RedHat/RPMS: cd RedHat/RPMS
4.Download the Package: mget dialog-*
5.Logout from the FTP server: bye
6.Install the package: rpm -ivh dialog-*
7.Verify the package either installed or not: rpm -q dialog
Create the directory /storage and group owner should be the sysusers group.
Answer and Explanation:
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
There are Mail servers, Web Servers, DNS Servers and Log Server. Log Server is already configured. You should configure the mail server, web server and dns server to send the logs to log server.
Answer and Explanation:
According to question, log server is already configured. We have to configure the mail, web and dns server for log redirection.
In mail, web and dns server:
1.vi /etc/syslog.conf
mail.*@logserveraddress
2.service syslog restart
mail is the facility and * means the priority. It sends logs of mail services into log server.
Create the group named sysadmin.
Answer and Explanation:
1.groupadd sysadmin
groupadd command is used to create the group and all group information is stored in /etc/group file.
There are three Disk Partitions /dev/hda8, /dev/hda9, /dev/hda10 having size 100MB of each partition. Create a Logical Volume named testvolume1 and testvolume2 having a size 250MB. Mount each Logical Volume on lvmtest1, lvmtest2 directory.
Answer and Explanation:
Steps of Creating LVM:
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.
One Domain RHCE is configured in your lab, your domain server is
server1.example.com. nisuser2001, nisuser2002, nisuser2003 user are created on your server 192.168.0.254:/rhome/stationx/nisuser2001. Make sure that when NIS user login in your system automatically mount the home directory. Home directory is separately shared on server /rhome/stationx/ where x is your Station number.
Answer and Explanation:
1. use the authconfig or system-config-authentication
2. Select the [*] USE NIS
3. Type the NIS Domain: RHCE
4. Type Server 192.168.0.254 then click on next and ok
5. You will get a ok message.
6. Create a Directory /rhome/stationx where x is your station number.
6. vi /etc/auto.master and write at the end of file
/rhome/stationx /etc/auto.home --timeout=60
7. vi /etc/auto.home and write
* -rw,soft,intr 192.168.0.254:/rhome/stationx/&
Note: please specify your station number in the place of x.
8. Service autofs restart
9. Login as the nisuser2001 or nisuser2002 on another terminal will be
Success.
According to question, RHCE domain is already configured. We have to make a client of RHCE domain and automatically mount the home directory on your system. To make a member of domain, we use the authconfig or system-config-authentication command. There a 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 used the /etc/auto.master file. On /etc/auto.master file we specified the mount point the configuration file for mount point.
Who ever creates the files/directories on /archive group owner should be automatically should be the same group owner of /archive.
Answer and Explanation:
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
Add a job on Cron schedule to display Hello World on every two Seconds in terminal 8.
Answer and Explanation:
1.cat >schedule
*/2 * * * * /bin/echo “Hello World” >/dev/tty8
Cron helps to schedule on recurring events. Pattern of Cron is:
MinuteHourDay of MonthMonth Day 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
Raw printer named printerx where x is your station number is installed and shared on server1.example.com. Install the shared printer on your PC to connect shared printer using IPP Protocols. Your server is 192.168.0.254.
Answer and Explanation:
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
Create the user named jane and john.
Answer and Explanation:
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.
Create the partition having 100MB size and mount it on /mnt/neo
Answer and Explanation:
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: ext2online /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.
There are more then 400 Computers in your Office. You are appointed as a System Administrator. But you don’t have Router. So, you are going to use your One Linux Server as a Router. How will you enable IP packets forward?
Answer and Explanation:
1. /proc is the virtual filesystem, we use /proc to modify the kernel parameters at running time.
# echo “1” >/proc/sys/net/ipv4/ip_forward
2. /etc/sysctl.conf when System Reboot on next time, /etc/rc.d/rc.sysinit scripts reads the file /etc/sysctl.conf. To enable the IP forwarding on next reboot also you need to set the parameter.
net.ipv4.ip_forward=1
Here 0 means disable, 1 means enable.
There is one partition /dev/hda14 mounted on /data. The owner of /data is root user and root group. And Permission is full to owner user, read and execute to group member and no permission to others. Now you should give the full permission to user user1 without changing pervious permission.
Answer and Explanation:
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
/dev/hda14/dataext3defaults,acl0 1
Make Successfully Resolve to server1.example.com where DNS Server is 192.168.0.254.
Answer and Explanation: 1. vi /etc/resolv.conf
Write : nameserver 192.168.0.254
Successfully resolv to server1.example.com where your DNS server is 172.24.254.254
Answer and Explanation:
nameserver 172.24.254.254
On every clients, DNS server is specified in /etc/resolv.conf. When you request by name it tries to resolv from DNS server .
Dig Server1.example.com, Resolve to successfully through DNS Where DNS server is 172.24.254.254
Answer and Explanation:
#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 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 the named daemon, 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.