Oracle Oracle Certifications 1Z0-100 Questions & Answers

• Question 61:

  Consider the output shown:

  # rpm –i sendmail-cf-8.14.4-8.e16.noarch.rpm Error: Failed dependencies:

  Sendmail = 7.14.4-8.e16 is needed by sendmail-cf-8.e16.noarch # rpm –i sendmail-8.14.4-8.e16.x86_64.rpm # rpm –i sendmail-cf-8.14.4-8.e16.noarch.rpm # rpm -q sendmail sendmail-cf Sendmail-8.14.4-8.e16.x86_64 Sendmail-cf-8.e16_64 Sendmail-cf-8.14.4-8.e16.noarch # rpm –e sendmail

  Which statement is true about the execution of the rpm -e sendmail command?

  A. It erases the sendmail package without errors.

  B. It fails with an error because the package version is not supplied on the command line.

  C. It fails with an error because the sendmail-cf package depends on the sendmail package.

  D. It erases the sendmail package and raises an error because the sendmail package depends on the sendmail package.

  E. It erases both the sendmail and sendmail-cf packages because the sendmail-cf package depends on the sendmail package.

  Correct Answer: E

• Question 62:

  Which three statements are true about the User Private Group scheme in Oracle Linux?

  A. If a user jules is added with the useradd jules command, a group called jules_grp is also created

  B. The umask for the jules user is 002 in /etc/bashrc

  C. Users belonging to a group to which user jules also belongs, are automatically able to write to the private group belonging to the jules user.

  D. If a user jules is added with the user add jules command, a group called jules is also added. but no other user may be a member of that group.

  E. A directory owned by a group to which several users belong, and which has the setgid fa turned on, has shared write access to all members of the group.

  F. The User private Group scheme is enabled by default in Oracle Linux.

  Correct Answer: DEF

  DF (not A): By default, Oracle Linux implements the user private group (UPG) scheme where adding a user account also creates a corresponding UPG with the same name as the user, and of which the user is the only member.

  E: When setgid permission is applied to a directory, files that were created in this directory belong to the group to which the directory belongs, not the group to which the creating process belongs. Any user who has write and execute permissions in the directory can create a file there. However, the file belongs to the group that owns the directory, not to the user's group ownership.

• Question 63:

  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

  Correct Answer: C

  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.

• Question 64:

  Which type of nameserver is provided by the default bind configuration files on Oracle Linux?

  A. A primary name server

  B. A secondary name server

  C. Recursive caching-only nameserver

  D. An authoritative name server

  E. Slave name server

  Correct Answer: A

• Question 65:

  Which three statements are true concerning the IPTABLES Oracle Linux firewall?

  A. The default rule table is filter.

  B. iptables has two main components: the kernel component netfilter and the command-line utility ipchains.

  C. Input, output, and forward are the rule tables associated with filter.

  D. PREROUTING, OUTPUT, and POSTROUTING are the chains associated with nat.

  E. The main rule chains are filter, nat, and mangle.

  F. The main rule tables are filter, nat, and mangle.

  Correct Answer: ADF

  A: You need to specify the table and the chain for each firewall rule you create. There is an exception: Most rules are related to filtering, so iptables assumes that any chain that's defined without an associated table will be a part of the filter table. The filter table is therefore the default.

  D: Nat Network Address Translation PREROUTING Address translation occurs before routing. Facilitates the transformation of the destination IP address to be compatible with the firewall's routing table. Used with NAT of the destination IP address, also known as destination NAT or DNAT. POSTROUTING Address translation occurs after routing. This implies that there was no need to modify the destination IP address of the packet as in pre-routing. Used with NAT of the source IP address using either one-to-one or many-to-one NAT. This is known as source NAT, or SNAT. OUTPUT Network address translation for packets generated by the firewall. (Rarely used in SOHO environments)

  F: There are three tables in total. The first is the mangle table which is responsible for the alteration of quality of service bits in the TCP header. The second table is the filter queue which is responsible for packet filtering. It has three built-in chains in which you can place your firewall policy rules. The third table is the nat queue which is responsible for network address translation.

• Question 66:

  Which two statements are true about signal handling in Oracle Linux?

  A. The pkill command kills a process by name.

  B. A process killed with the default signal always terminates gracefully if it: does not block the kill request.

  C. The kill command sends a sigkill (signal 9) by default to the process being killed.

  D. The kill command may send a termination signal to more than one process at a time.

  E. All signals may be blocked by a process.

  Correct Answer: BD

  D: The kill command is used to send a termination signal to the specified process or group.

  Incorrect:

  Not A: The following example shows the xscreensaver process (2609) which is to be terminated.

  $ pgrep xscreen

  $ kill 2609

  Though we use pgrep to find the PID of this process here we could have also used a PID from the output

  of top or ps.

  Not C: The kill command is used to send a termination signal to the specified process or group. The default

  termination signal is a SIGTERM (15) signal. Not E: When there a stubborn process trapping the kill

  command and refusing to terminate, the -9 (SIGKILL) signal should be used to kill the process. The -9

  signal cannot be trapped by a process and ignored.

• Question 67:

  Which three statements are true concerning filesystems supported by Oracle Linux?

  A. An ext3 filesystem can be mounted as an ext2 filesystem.

  B. An ext4 filesystem can be mounted as an ext3 filesystem.

  C. The ext3 and ext4 filesystems both support multiple journaling modes.

  D. The btrfs filesystem includes a volume manager.

  E. The btrfs filesystem cannot be used for the root filesystem.

  F. The ext4 filesystem is a copy-on-write filesystem.

  Correct Answer: ACE

  A: ext2 file systems are upgradeable to ext3 without reformatting.

  C: The ext3 file system includes journaling capabilities to improve reliability and availability. In addition to the features of ext3, the ext4 file system supports extents (contiguous physical blocks), pre-allocation, delayed allocation, faster file system checking, more robust journaling, and other enhancements.

  Incorrect:

  Not F: btrfs, not ext4, is a copy-on-write file system,

• Question 68:

  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 # # sshd Start up the OpenSSH server daemon # # chkconfig: 2345 55 25 # 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.

  Correct Answer: D

• Question 69:

  For which three types of installs does the Oracle database Pre-install rpm help by installing required software packages and setting system parameters?

  A. Oracle Database 11g Enterprise Edition single instance

  B. Oracle WebLogic

  C. Oracle Database Enterprise Edition Real Application Cluster

  D. Oracle Enterprise Manager Cloud Control

  E. Oracle Database 11g Standard Edition single instance

  Correct Answer: ABE

• Question 70:

  Users complain that system performance is unacceptable when using a specific application service running on a multiprocessor service.

  You have established from the storage team that disk response times have not increased, so you can discount there being an I/O problem.

  You run vmstat to look at CPU activity and notice high average disk times on the multiprocessor system and an average run queue of zero.

  You require more detail about each CPU from which the vmstat figures are derived, to investigate if the load is distributed evenly across all CPUs.

  Which three commands provide more detailed information about CPU load distribution?

  A. iostat x

  B. top

  C. mpstat

  D. vmstat

  E. sar

  Correct Answer: CDE

  C: A useful command to get CPU related stats is mpstat. Here is an example output:

  # mpstat -P ALL 5 2 Linux 2.6.9-67.ELsmp (oraclerac1) 12/20/2008

  10:42:38 PM CPU %user %nice %system %iowait %irq %soft %idle intr/s

  10:42:43

  PM all 6.89 0.00 44.76 0.10 0.10 0.10 48.05 1121.60

  10:42:43

  PM 0 9.20 0.00 49.00 0.00 0.00 0.20 41.60 413.00

  10:42:43

  PM 1 4.60 0.00 40.60 0.00 0.20 0.20 54.60 708.40 etc.

  D: When called, the grand-daddy of all memory and process related displays, vmstat, continuously runs and posts its information. It takes two arguments:

  # vmstat

  is the interval in seconds between two runs. is the number of repetitions vmstat makes.

  Here is a sample when we want vmstat to run every five seconds and stop after the tenth run. Every line in

  the output comes after five seconds and shows the stats at that time.

  # vmstat 5 10

  procs -----------memory---------- ---swap-- -----io---- --system-- ----cpu---- r b swpd free buff cache si so bi bo

  in cs us sy id wa 0 0 1087032 132500 15260 622488 89 19 9 3 0 0 4 10 82 5 0 0 1087032 132500 15284

  622464 0 0 230 151 1095 858 1 0 98 1 0 0 1087032 132484 15300 622448 0 0 317 79 1088 905 1 0 98 0

  ... shows up to 10 times.

  The output shows a lot about the system resources.

  E: sar stands for System Activity Recorder, which records the metrics of the key components of the Linux

  system--CPU, Memory, Disks, Network, etc.--in a special place: the directory /var/log/sa.

  The simplest way to use sar is to use it without any arguments or options. Here is an example:

  # sar Linux 2.6.9-55.0.9.ELlargesmp (prolin3) 12/27/2008

  12:00:01 AM CPU %user %nice %system %iowait %idle

  12:10:01 AM all 14.99 0.00 1.27 2.85 80.89

  12:20:01 AM all 14.97 0.00 1.20 2.70 81.13

  12:30:01 AM all 15.80 0.00 1.39 3.00 79.81

  12:40:01 AM all 10.26 0.00 1.25 3.55 84.93

  Incorrect:

  Not A: iostat is for I/O