1Z0-100 | The Rebirth Guide To 1Z0-100 exam question
Q11. The SSHD service is controlled by the script in /etc/init.d/sshd, part of which is shown here:
[root@FAROUT ~] cat /etc/init.d/sshd # !/bin/bash # # sshdStart up the OpenSSH server daemon # # chkconfig: 23455525 # description: SSH is a protocol for secure remite shell access. # This service starts up the Open SSH server daemon. #
You issue chkconfig commands to change the sshd service:
[root@FAROUT ~] # chkconfig sshd off [root@FAROUT ~] # chkconfig sshd reset
What is the result of the two commands issued?
A. The sshd service configuration is restored to the settings that existed before setting it off.
B. The sshd service configuration is restored to start In run levels 2, 3, 4 and 5.
C. The sshd service configuration is restored to start in run levels 2 and 5 only.
D. The sshd service configuration is restored to those that existed after the operating system was first installed.
Answer: D
Q12. What is the main advantage of the Oracle Unbreakable Enterprise Kernel compared with the Red Hat compatible kernel?
A. It is more secure and, therefore, more difficult to hack.
B. It has a lower Mean Time Between Failures.
C. It provides higher availability for applications by reducing Mean Time to Recovery.
D. It scales better for more CPUS, memory, and Infiniband network connections.
Answer: D
Explanation: The Unbreakable Enterprise Kernel, for those who want to leverage the
latest features from
mainline Linux and boost performance and scalability.
The Red Hat Compatible Kernel, for those who prefer strict Red Hat kernel ABI (kABI)
compatibility.
Q13. Bash is invoked as an interactive login shell.
What is the order in which the bash configuration files are read, assuming that all the files exist in their correct location and are readable?
A. /etc/profile, ~/ .profile
B. /etc/profile, ~/ .bash_profile
C. /etc/profile, ~/ .bash_profile, ~/ .bash_login, ~/ .profile
D. /etc/profile, ~/ .bash_profile, ~/ .profile, ~/ .bash_login
Answer: C
Explanation: When Bash is invoked as an interactive login shell, or as a non-interactive shell with the --login option, it first reads and executes commands from the file /etc/profile, if that file exists. After reading that file, it looks for ~/.bash_profile, ~/.bash_login, and ~/.profile, in that order, and reads and executes commands from the first one that exists and is readable. The --noprofile option may be used when the shell is started to inhibit this behavior.
When a login shell exits, Bash reads and executes commands from the file ~/.bash_logout, if it exists.
Q14. Which four statements are true concerning the various stages of GRUB bootloader in Oracle Linux?
A. GRUB stage1 must always load stage1_5.
B. GRUB stage1_5 is used to process the /boot/grub/grub.conf file.
C. GRUB stage1_5 loads GRUB stage2.
D. GRUB stage1 may load GRUB stage2 directly.
E. GRUB stage1 provides support for several different filesystems, enabling stage1 to load stage1_5.
F. GRUB stage1_5 provides support for several different filesystems, enabling stage1_5 to load stage2.
G. GRUB stage2 is used to process the /boot/grub/grub.conf file.
Answer: C,D,E,G
Explanation: CD: Stage 1 code is stored in the MBR. This code contains a block list that
points to the next stage of GRUB, which is either stage1_5 or stage 2, depending on the
file system type.
E(not F): Stage1_5 code allows GRUB to interpret different types of file system
G (not B): Stage 2 code reads /boot/grub/grub.conf to determine how to load the kernel.
Incorrect:
Not A:. For some file system types such as ext4, GRUB does not need to load stage1_5.
Q15. A web server on HOST01 is listening on port 80.
Examine the IPTABLES rule shown: [root@host01 ~] # iptables –L INPUT Chain INPUT (policy ACCEPT) targetportoptsourcedestination
ACCEPTtcp- - anywhereanywheretcp dpt:http Another rule is then added: [root@host01 ~] # iptables –A INPUT –P tcp - - dport 80 –j REJECT What is the effect of this command on subsequent attempts to access the web server on
HOST01 using port 80?
A. New connection attempts timeout.
B. New connection attempts are refused and the client informed of the refusal.
C. New connection attempts always succeed.
D. New connection attempts succeed until a reload of the firewall rules.
Answer: A
Q16. Examine the channel specification in the /etc/yum.repos.d/public-yum-016.repo file: # head -6 /etc/yum.repos.d/public-yum-016.repo
[016_latest]
Name=Oracle Linux $releasever Latest ($basearch)
Baseurl=http://public-yum.oracle.com/repo/oracleLinux/OL6/latest/$basearch/
Gpgkey=http://public-yum.oracle.com/RPM-CPG-KEY-oracle-o16
Gpgcheck=1
Enabled=0
What is the effect of the enabled=0 setting?
A. This channel is disabled and cannot be used by YUM at all.
B. This channel will not be used by YUM when searching for packages.
C. By default, YUM will not use this channel but this can be overridden on the command line.
D. This channel will not be used by YUM when it searches for packages, but YUM will check if updates exist for packages already installed from this channel.
Answer: B
Explanation: Disable YUM Repo (Repository) Disable YUM Repo Edit repo file on /etc/yum.repos.d/ as root and change enabled to 0 ## Change enabled=1
## To enabled=0
Q17. Which three statements are true about the shared directories defined in the /etc/exports file?
A. By default, a directory is shared with no root squashed.
B. By default, a directory is shared read write.
C. By default, a directory is shared with root squashed.
D. By default, a directory is shared read only.
E. By default, a directory is shared sync.
Answer: C,D,E
Explanation: C (not A): Very often, it is not desirable that the root user on a client machine is also treated as root when accessing files on the NFS server. To this end, uid 0 is normally mapped to a different id: the so-called anonymous or nobody uid. This mode of operation (called 'root squashing') is the default, and can be turned off with no_root_squash.
E: In releases of nfs-utils up to and including 1.0.0, the async option was the default. In all releases after 1.0.0, sync is the default, and async must be explicitly requested if needed.
Q18. Examine this output:
# df –t nfs
FilesystemSizeUsedAvailUse%Mounted on o16:export30G21G7.6G74%/mnt # 1s -1 /mnt/nfs.sh
-rwxr-mr-x. 1 root root 22 May 8 16:37 /mnt/nfs.sh
# file /mnt/nfs.sh /mnt/nfs.sh: Bourne-Again shell script text executables # /mnt/nfs.sh
bash: /mnt/nfs.sh: Permission denied What is the reason for the error?
A. The file system was exported on host o16 using the ROOT_SQUASH option.
B. The /export filesystem was mounted with the NOEXEC option on host o16.
C. The filesystem mounted on /mnt was mounted with the NOEXEC option.
D. The filesystem was exported on host o16 by using the NO_ROOT_SQUASH option.
Answer: C
Q19. Which three statements are true concerning the use of the grub menu in Oracle Linux?
A. All changes made using the grub editor at boot time are saved by default to /boot/grub/grub, conf.
B. Additional parameters may be passed to the selected kernel.
C. The initrd directive may not be changed.
D. Existing kernel parameters may be changed.
E. Some of the GRUB command-line functions may be password protected.
Answer: A,B,D
Explanation: A: GRUB requires only the file name and drive partitions to load a kernel.
You can configure this information by editing the /boot/grub/grub.conf file, by using the
GRUB menu, or by entering it on the command line.
Incorrect:
not C: If you have set a GRUB password, you must press P and enter the valid password
to be able to edit the titles or change kernel boot parameters. To edit any of the root,
kernel, or initrd directives, press E. To edit the kernel directive only, press A. To use the
GRUB command line, press C.
If you press E, select the root, kernel, or initrd directive, and press E to edit it.
Not E: Grub can be password protected, but not individual functions.
Q20. Which two statements are true concerning the installation and configuration of the bootloader by the Anaconda installer, which is then used to boot Oracle Linux?
A. The Linux Loader (LILO) bootloader may be chosen for installation.
B. The bootloader must be password protected and Anaconda prompts for a password in all cases.
C. The Grand Unified Bootloader (GRUB) is the only bootloader used by Oracle Linux.
D. If previously installed operating systems are found on disk partitions that were not overwritten, then an attempt is made to configure the bootloader to be able to boot them.
E. The bootloader is installed by default in the first partition of the disk.
Answer: A,E
Explanation: A (not C): Linux boot process from hard drive:
1. PC initializion phase - BIOS, POST.
2. PC starts boot loader - usually grub or lilo.
3. The bootloader locates kernel image on the hard drive.
4. The kernel decompresses and loads itself. Once finished it tries to mount the root filesystem. 5. When the root filesystem is mounted, /sbin/init is executed and continues booting the system using inittab and /etc/rc*.d scripts