1Z0-460 | Abreast of the times 1Z0-460 Exam Study Guides With New Update Exam Questions
Q11. What does the following btrfs command do?
$ sudo btrfs subvolume snapshot src src-01
A. Creates snapshots of the src src-01 subvolumes
B. Creates a snapshot of the src-01 subvolumes in src
C. Creates the src and src-01 subvolumes and takes a snapshot of these subvolumes
D. Creates a snapshot of the src subvolumes in src-01
Answer: D
Explanation: *To create a snapshot use
sudo btrfs subvolume snapshot /mnt/@ /mnt/@_snapshot this will create a snapshot of the @ subvolume named @_snapshot located also in the top of the btrfs tree.
*btrfs subvolume snapshot <source> [<dest>/]<name> Create a writable snapshot of the subvolume <source> with the name <name> in the <dest> directory.
Q12. You have to collect information about your Oracle Linux 6 system, such as hardware configuration, installed software packages, configuration, and operational state send it to Oracle Support. Which tool will help you gather this information for sending it to Oracle Support?
A. sosreport
B. iostat
C. kdump
D. strace
E. systemstat
Answer: A
Explanation: sosreport - Generate debugging information for this system
sosreport generates a compressed tarball of debugging information for the system it is run on that can be sent to technical support reps that will give them a more complete view of the overall system status.
Incorrect: Not B:The iostat command is used for monitoring system input/output device loading by observing the time the devices are active in relation to their average transfer rates. The iostat command generates reports that can be used to change system configuration to better balance the input/output load between physical disks.
Not C:kdump.conf is a configuration file for the kdump kernel crash collection service.
kdump.conf provides post-kexec instructions to the kdump kernel. It is stored in the initrd file managed by the kdump service. If you change this file and do not want to restart before it takes effect, restart the kdump service to rebuild to initrd.
Not D:strace - trace system calls and signals
Q13. You have to collect data by using the OS Watcher tool to help diagnose a performance issue on your Oracle Linux system. You need to collect data every 30 seconds by using this tool and archive this data for a period of three days. Which is the OS Watcher tool option that can be used to collect this data from your system?
A. # ./startOSWbb.sh –t 30 –p 3
B. # ./startOSWbb.sh 30 72
C. # ./startOSWbb.sh –int = 30 –days = 3
D. # ./startOSWbb.sh 30 3
Answer: B
Explanation: Example:
/startOSWbb.sh 60 24
collect every 1 minute and keep 24 hours of archive files.
Q14. You run the following command as the root user to set properties of a network interface (eth0):
# ifconfig eth0 192.0.2.102 netmask 255.255.255.0 up
Setting network interface properties with the ifconfig utility is not persistent across system reboots. Which file would you edit to make settings and to make them persist across system reboots?
A. /etc/sysconfig/network file
B. /etc/sysconfig/network/ifcg-eth0 file
C. /etc/sysconfig/network-scripts/ifcfg-eth0 file
D. /etc/sysconfig/network-scripts/eth0 file
Answer: C
Explanation: Modifytheeth0config file Opentheconfiguration using a text editor such as vi/vim, and make sure file read as follows for eth0 interface # vi /etc/sysconfig/network-scripts/ifcfg-eth0
Q15. The DBA tells you that the system is not overloaded but you can tell that the system us actively swapping. What command would you run to show this information to the DBA?
A. # iotop
B. # iostat 5 10
C. # cat /proc/meminfo
D. # vmstat 5 10
Answer: B
Explanation: *iostat - Report Central Processing Unit (CPU) statistics and input/output statistics for devices, partitions and network filesystems (NFS).
*The iostat command is used for monitoring system input/output device loading by observing the time the devices are active in relation to their average transfer rates. The iostat command generates reports that can be used to change system configuration to better balance the input/output load between physical disks.
Incorrect:
Not A: Related to kernel and processes. *iotop - simple top-like I/O monitor *iotop watches I/O usage information output by the Linux kernel (requires 2.6.20 or later) and displays a table of current I/O usage by processes or threads on the system.
*iotop displays columns for the I/O bandwidth read and written by each process/thread during the sampling period. It also displays the percentage of time the thread/process spent while swapping in and while waiting on I/O. For each process, its I/O priority (class/level) is shown. In addition, the total I/O bandwidth read and written during the sampling period is displayed at the top of the interface.
Not C: related to RAM usage. *The entries in the /proc/meminfo can help explain what's going on with your memory usage, if you know how to read it. *High-Level Statistics MemTotal: Total usable ram (i.e. physical ram minus a few reserved bits and the kernel binary code) MemFree: Is sum of LowFree+HighFree (overall stat) MemShared: 0; is here for compat reasons but always zero. Buffers: Memory in buffer cache. mostly useless as metric nowadays Cached: Memory in the pagecache (diskcache) minus SwapCache SwapCache: Memory that once was swapped out, is swapped back in but still also is in the swapfile (if memory is needed it doesn't need to be swapped out AGAIN because it is already in the swapfile. This saves I/O)
Not D:vmstat - Report virtual memory statistics
Q16. You want to add a README.txt file in the home directory of every new user that you create by using the useradd command on your Oracle Linux system. In which directory will you place the README.txt file so that it automatically gets copied to the new user’s home directory when the user is created?
A. /home/users
B. /etc/default/useradd
C. /etc/default
D. /etc/skel
Answer: D
Explanation: -k, --skel SKEL_DIR
The skeleton directory, which contains files and directories to be copied in the user's home
directory, when the home directory is created by useradd.
This option is only valid if the -m (or --create-home) option is specified.
If this option is not set, the skeleton directory is defined by the SKEL variable in
/etc/default/useradd or, by default, /etc/skel.
Note:
*useradd - create a new user or update default new user information
Reference: man useradd
Q17. Which three things does oracle-edbms-server-11gR2-preinstall RPM package do to simplify the installation of Oracle Database on Oracle Linux 6 systems?
A. Downloads and installs various software packages and specific versions needed for Oracle database installation
B. Downloads and installs packages required for Oracle Database installation, runs the runInstaller utility to install the database, and then starts the database
C. Creates the Oracle user and the oinstall and dba groups, which are the default user and groups used during Oracle database installation
D. Modifies and sets kernel parameters in /etc/sysctl.conf and sets shell resource limits in /etc/security/limits.conf based on the Oracle Database Server installation requirements
E. Checks whether all packages are installed to support RDBMS and then calls the Oracle Universal Installer utility to install RDBMS and then calls the Oracle Universal Installer utility to install RDBMS
Answer: A,C,D
Explanation: In order to install the Oracle Database 11g R2 on Oracle Linux 6, your system needs to meet a few prerequisites, as outlined in the Linux Installation Guides. Using the Oracle RDBMS Server 11gR2 Pre-install RPM, you can complete most of the pre-installation configuration tasks.
The package:
* (A)Causes the download and installation of various software packages and specific versions needed for database installation, with package dependencies resolved via yum
* (C)Creates the user oracle and the groups oinstall and dba, which are the defaults used during database installation
* (D)Modifies kernel parameters in /etc/sysctl.conf to change settings for shared memory, semaphores, the maximum number of file descriptors, and so on
* (D)Sets hard and soft shell resource limits in /etc/security/limits.conf, such as the number of open files, the number of processes, and stack size to the minimum required based on the Oracle Database 11g Release 2 Server installation requirements *Sets numa=off in the kernel boot parameters for x86_64 machines
Q18. Which file system is both new and now installed by default in Oracle Linux 6 with Unbreakable Enterprise Kernel (UEK)?
A. ext4
B. ext3
C. zfs
D. ext2
E. fat64
Answer: A
Explanation: Oracle Linux 6 includes many new features, including:
ext4 filesystem
The ext4 filesystem is installed by default.
Q19. The ASMlib on Linux us designed to ___________.
A. Make managing ASM volume easier.
B. Make managing ASM volumes easier and provide a performance improvement over ASM volumes alone.
C. Provide load balancing across multiple volumes.
D. Allow the user to list contents of the volume from the OS command line.
Answer: B
Explanation: ASMLib is an optional support library for the Automatic Storage Management feature of the Oracle Database. ASMLib allows an Oracle Database using ASM more efficient and capable access to the disk groups it is using.
Q20. What are the two benefits of configuring network interface bonding?
A. aggregating two or more Network Interfaces (NICs) toactas one logical interface
B. creating a static address that is bound to one NIC
C. providing either failover or load-balancing to two or more Network Interfaces (NICs)
D. binding a network interface to the embedded firewall (IPTables) for port filtering
Answer: A,C
Explanation: Network bonding refers to the combination of network interfaces on one host for redundancy and/or increased throughput.