RH202 Real Exam Prep DEMO

Question 1: mount /dev/hda? /mnt/neo
4.CORRECT TEXT
Your System is going use as a router for 172.24.0.0/16 and 172.25.0.0/16. Enable the IP
Forwarding.
Answer and Explanation:
1. echo "1" >/proc/sys/net/ipv4/ip_forward
2. 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.
5.CORRECT TEXT
Some users home directory is shared from your system. Using showmount -e localhost command, the
shared directory is not shown. Make access the shared users home directory.
Answer and Explanation:
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.
6.CORRECT TEXT
neo user tried by:
dd if=/dev/zero of=/home/neo/somefile bs=1024 count=70
files created successfully. Again neo tried to create file having 70K using following command:
dd if=/dev/zero of=/home/neo/somefile bs=1024 count=70
But he is unable to create the file. Make the user can create the file less then 70K.
Answer and Explanation:
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 /home ext3 defaults,usrquota 0 0 ¨¤ To enale 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 update
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.
Verify using the repquota /home command.
7.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.
8.CORRECT TEXT
Quota is implemented on /data but not working properly. Find out the
Problem and implement the quota to user1 to have a soft limit 60 inodes
(files) and hard limit of 70 inodes (files).
Answer and Explanation:
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 /data ext3 defaults,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.
9 CORRECT TEXT
One Logical Volume named lv1 is created under vg0. The Initial Size of that Logical Volume is 100MB.
Now you required the size 500MB. Make successfully the size of that Logical Volume
500M without losing any data. As well as size should be increased online.
Answer and Explanation:
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. resize2fs /dev/vg0/lv1 ¨¤ to bring extended size online.
5. Again Verify using lvdisplay and df -h command.
10 CORRECT TEXT
Create one partitions having size 100MB and mount it on /data.
Answer and Explanation:
1. Use fdisk /dev/hda ¨¤To create new partition.
2. Type n ¨¤For New partitions
3. It will ask for Logical or Primary Partitions. Press l for logical.
4. It will ask for the Starting Cylinder: Use the Default by pressing Enter Key.
5. Type the Size: +100M ¨¤You can Specify either Last cylinder of Size here.
6. Press P to verify the partitions lists and remember the partitions name.
7. Press w to write on partitions table.
8. Either Reboot or use partprobe command.
9. Use mkfs -t ext3 /dev/hda?
Ormke2fs -j /dev/hda? ¨¤ To create ext3 filesystem
10. vi /etc/fstab
Write:
/dev/hda? /data ext3 defaults 1 2
11. Verify by mounting on current Sessions also:
mount /dev/hda? /data
11.CORRECT TEXT
You are new System Administrator and from now you are going to handle the system and yourmain 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
12.CORRECT TEXT
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 tme, /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.
13.CORRECT TEXT
You Completely Install the Redhat Enterprise Linux 5 on your System. While start the system, it's giving
error to load X window System. How will you fix that problem and make boot successfully run X Window
System.
Answer and Explanation:
Think while Problems occurred on booting System on Runlevel 5 (X Window).
1. /tmp is full or not
2. Quota is already reached
3. Video card or resolution or monitor is misconfigured.
4. xfs service is running or not.
Do These:
1. df -h /tmp ¨¤ /tmp is full remove the unnecessary file
2. quota username ¨¤if quota is already reached remove unnecessary file from home directory.
3. Boot the System in runlevel 3.¨¤you can pass the Kernel Argument from boot loader.
4. Use command: system-config-display ¨¤ It will display a dialog o configure the monitor, Video card,
resolution etc.
5. Set the Default Runlevel 5 in /etc/inittab
id:5:initdefault:
6. Reboot the System you will get the GUI login Screen.
14.CORRECT TEXT
There are two different networks, 192.168.0.0/24 and 192.168.1.0/24. Your System is in
192.168.0.0/24 Network. One RHEL 5 Installed System is going to use as a Router. All required
configuration is already done on Linux Server. Where 192.168.0.254 and 192.168.1.254 IP
Address are assigned on that Server. How will make successfully ping to 192.168.1.0/24
Network's Host?
Answer and Explanation:
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
15.CORRECT TEXT
Make a swap partition having 100MB. Make Automatically Usable at System Boot Time.
Answer and Explanation:
1. Use fdisk /dev/hda ¨¤To create new partition.Type n ¨¤ For New partitionIt will ask foLogical 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 Speciy 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
NumberType 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? swap swap defaults 0 0Reboot the System and verify that swap is automatically
enabled or not.
16.CORRECT TEXT
You are a System administrator. Using Log files very easy to monitor the system. Now there are 50
servers running as Mail, Web, Proxy, DNS services etc. You want to centralize the logs from all servers
into on LOG Server. How will you configure the LOG Server to accept logs from remote host ?
Answer and Explanation:
By Default system accept the logs only generated from local host. To accept the Log from other host
configure:vi /etc/sysconfig/syslog
SYSLOGD_OPTIONS="-m 0 -r"
Where
-m 0 disables 'MARK' messages.
-r enables logging from remote machines
-x disables DNS lookups on messages recieved with -r
service syslog restart
17.CORRECT TEXT
You are giving the debug RHCT exam. The examiner told you that the password of root is redhat.
When you tried to login displays the error message and redisplayed the login screen. You
changed the root password, again unable to login as a root. How will you make Successfully Login as a
root.
Answer and Explanation:
When root unable to login into the system think:
1. Is password correct?
2. Is account expired?
3. Is terminal Blocked?
Do these Steps:
3. Boot the System on Single user mode.
4. Change the password
5. Check the account expire date by using chage -l root command.
If account is expired, set net expire date: chage -E "NEVER" root
4. Check the file /etc/securetty ¨¤ Which file blocked to root login from certain terminal.
5. If terminal is deleted or commented write new or uncomment.
6. Reboot the system and login as a root.