Oracle 1z0-106 Dumps

Understanding the Automounter Configuration:

/etc/auto.master:

/net -hosts

/- auto.direct ro

The /- auto.direct ro line indicates:

Mount Point Prefix:/ (direct mounts)

Map File:auto.direct

Global Mount Options:ro (read-only)

/etc/auto.direct:

/nfs1 host01:/export/share1

/nfs2 -sync host01:/export/share2

/nfs3 host02:/export/share3

/nfs1 and /nfs3:

No specific mount options in auto.direct.

Inherit the ro option from /etc/auto.master.

/nfs2:

Specifies -sync option in auto.direct.

Inherits ro from /etc/auto.master.

Mount options are ro,sync.

Mount Options Resolution:

Global Options (ro) apply to all entries unless overridden.

Per-Entry Options in auto.direct override or supplement global options.

Effective Mount Options:

/nfs1:

ro (from /etc/auto.master)

Default NFS options (async unless sync is specified)

/nfs2:

ro (from /etc/auto.master)

sync (specified in auto.direct)

/nfs3:

ro (from /etc/auto.master)

Default NFS options (async)

Oracle Linux Reference:

Oracle® Linux 8: Configuring File Systems-Automounter Configuration:

"Options specified in the master map apply to all entries in the map unless overridden by entries in the map itself."

NFS Default Options:

"By default, NFS mounts are asynchronous (async) unless the sync option is specified."

Conclusion:

/nfs1 and /nfs3:Mounted with ro,async.

/nfs2:Mounted with ro,sync.

Correct Option:A

Option C (Correct):The-k passpart of theauditctlcommand defines a keyword (pass) for the audit rule. This keyword helps in filtering and searching logs in the audit trail.

Option D (Correct):The-w /etc/passwd -p wpart of the command sets up a watch on the/etc/passwdfile for write (w) operations. This audit rule will generate a log entry every time there is a write operation to/etc/passwd.

Option A (Incorrect):This command does not write directly to/etc/audit/rules.d/audit.rules; it defines a rule in memory that could be saved to this file later.

Option B (Incorrect):The rule only logs write (w) operations; it does not log read operations.

Option E (Incorrect):The command does not directly cause a write to/etc/audit/audit.rules.

Oracle Linux Reference:Refer to:

Oracle® Linux 8: Auditing and System Logs

man auditctlfor details on audit rules and options.

Explanation of Answer D:Theinitramfs(initial RAM filesystem) is a temporary filesystem loaded into memory during the boot process, containing essential drivers and utilities. The kernel usesinitramfsto load necessary drivers and modules required to access the root file system, particularly if it resides on a disk that requires special drivers.

Explanation of Answer E:Both thevmlinuz(the compressed Linux kernel image) and theinitramfsfile are located in the/bootdirectory. The bootloader, such as GRUB, reads these files from/bootto start the system.

Option D (Correct):The commandsetfacl --modify user:user2:r-x my_directorysets an Access Control List (ACL) entry that givesuser2read (r) and execute (x) permissions onmy_directory. The execute (x) permission is required to allow navigation into the directory.

Option A (Incorrect):The--defaultoption would set the default ACL for future files or directories created withinmy_directory, not the directory itself.

Option B (Incorrect):This option gives only read (r) permission, but without execute (x) permission,user2cannot navigate into the directory.

Option C (Incorrect):The-xoption is used to remove an ACL entry, not modify it.

Option E (Incorrect):This modifies the ACL for the grouptestinstead of the useruser2.

Oracle Linux Reference:Refer to:

Oracle® Linux 8: Using Access Control Lists

Option C (Correct):Thedmesg -Tcommand converts the timestamps in the kernel ring buffer messages to a human-readable format. The defaultdmesgoutput shows the timestamps in a raw format (seconds since the kernel started), while the-Toption translates these timestamps into a human-readable date and time.

Option A (Incorrect):The-toption is used to remove the timestamps entirely from the output.

Option B (Incorrect):The-xoption provides extended information about the message (e.g., facility, level).

Option D (Incorrect):The-Woption waits for new messages and does not convert timestamps to a human-readable format.

Oracle Linux Reference:Refer to:

man dmesgfor more details ondmesgoptions.

Understanding AutoFS Behavior:

AutoFSautomatically mounts file systems when accessed and unmounts them after a period of inactivity (default is 5 minutes).

A file system remains mounted as long as it isactive, meaning processes are accessing files or directories within it.

Scenario Analysis:

First Session:

Changed to a directory under AutoFS control (mount point is active).

Second Session:

Changed to /etc (does not affect the first session).

Idle Time Expires:

AutoFS checks for idle mounts to unmount.

Implications:

The mount point remainsactivebecause the shell in the first session is in the AutoFS directory.

AutoFS willnotunmount the file system while it is active.

Oracle Linux Reference:

Oracle® Linux 8: Configuring File Systems-Using the Automounter:

"A file system remains mounted as long as there are open files or directories within it."

Correct Options:

Option B:The file system remains mounted until you log out from the first session.

Option E:The file system remains mounted until you switch to a directory outside the current mount point.

Why Other Options Are Incorrect:

Option A:Incorrect because the mount does not persist indefinitely; it's unmounted when no longer active.

Option C:Incorrect because the mount is still active; the timer does not cause unmounting in this case.

Option D:Incorrect because the second session does not influence the mount status in the first session.

Option B (Correct):Btrfs uses a copy-on-write mechanism for both data and metadata, which ensures that the file system is more resilient to crashes and data corruption.

Option E (Correct):Btrfs supports online resizing, meaning that you can change the size of a mounted Btrfs file system without unmounting it.

Option G (Correct):Btrfs automatically defragments files in the background to maintain performance.

Option A (Incorrect):While Btrfs does support mirroring, it is not strictly block device mirroring in the traditional sense like RAID; it uses a different approach to redundancy.

Option C (Incorrect):Btrfs is not a cluster file system; it is designed for local file systems.

Option D (Incorrect):While Btrfs can store small files efficiently, it is not its primary design goal compared to other file systems optimized specifically for small files.

Option F (Incorrect):Btrfs is a file system with integrated volume management capabilities but is not a general-purpose volume manager like LVM.

Oracle Linux Reference:Refer to:

Oracle® Linux 8: Btrfs File System

man btrfsfor features and management.

The530 Permission deniederror indicates that the user is not allowed to log in. In vsFTPd, if theUSERLIST_ENABLEoption is set toYESin/etc/vsftpd/vsftpd.conf, and theoracleuser is listed in/etc/vsftpd/user_list, that user is explicitly denied access to the FTP server.

Explanation of Answer A:

Network services running in a confined domain: SELinux provides domain confinement for services, ensuring they run with restricted access based on their defined policies.

The oracle user must be confined: The commandsemanage login -a -s guest_u oracleconfines theoracleuser to theguest_uSELinux user role, which is a confined role.

Access to files and directories based only on SELinux contexts: With SELinux enabled and the policy loaded, access is governed by SELinux contexts.

Persistent SELinux configuration across reboots: Thesetenforce enforcingcommand, combined with the appropriate policy configuration, ensures that SELinux remains in enforcing mode across reboots.

Users able to publish private HTML content: Thesetsebool -P http_enable_homedirs oncommand enables the use of user home directories for web content, allowing users to host personal web pages.

Option A (Correct):The/procfile system is a pseudo-file system that contains runtime system information (e.g., system memory, mounted devices, hardware configuration, etc.). Files such as/proc/meminfoand/proc/cpuinfoprovide detailed information about memory and CPUs, respectively.

Option C (Correct):The/sysfile system, also known as sysfs, provides a view of the kernel's device model. It contains information about system hardware, including CPUs and memory. For example,/sys/devices/system/cpu/contains directories and files that provide detailed information about each CPU.

Option B (Incorrect):The/sysfile system does not contain a list of running processes. Running processes are listed in the/procfile system, with each process having its own directory under/proc.

Option D (Incorrect):/procdoes not contain a list of network drivers specifically. Network driver information is available under/proc/net, but this does not equate to a list of drivers.

Option E (Incorrect):The/sysfile system does not contain a list of mounted devices. Mounted devices are listed in/proc/mountsor the/etc/mtabfile.

Oracle Linux Reference:For more details, see:

Oracle® Linux 8: The/procand/sysFile Systems.

Option A (Correct):A slice unit in systemd is a grouping mechanism used for hierarchical management of resources (such as CPU, memory, and I/O) among a group of processes.

Options B, C, D (Incorrect):These options do not correctly describe the role or characteristics of slice units in Oracle Linux 8.

Oracle Linux Reference:Refer to:

Oracle® Linux 8: Managing Services with systemd

Option A (Correct):In rsyslog, afilteris used to determine which messages should be selected for further processing. Filters can be based on different criteria such as facility, severity, or specific message content.

Option B (Correct):Anactionin rsyslog defines what to do with messages that match a filter. Actions can include writing to a log file, sending to a remote server, running a script, etc.

Option C (Incorrect):A parser is not typically a component for creating a new rsyslog rule; it is involved in interpreting message formats.

Option D (Incorrect):A module in rsyslog is a loadable component that provides additional capabilities, such as support for different protocols or output formats. It is not a direct component of a logging rule.

Option E (Incorrect):Security policy is unrelated to the basic components used for defining rsyslog rules.

Oracle Linux Reference:Refer to:

Oracle® Linux 8: Configuring Rsyslog

Explanation of Answer A:When thechrootcommand is executed with/jail, the environment is changed to use/jailas its new root directory. Inside this environment, only the directories and files copied into/jailare accessible. Since/jaildoes not contain a/rootdirectory, the commandcd(which defaults to changing to the user's home directory) will fail, displayingNo such file or directory. Thepwdcommand shows the root of the chroot environment (/), andlsdisplays the contents of/jail, which includesbinandlib64.

Option A (Correct):The rule is applied to both IPv4 and IPv6 packets. Theinettable is used for filtering both IPv4 and IPv6 traffic, and since the rule is added to theinettable, it affects both IP versions.

Option E (Correct):The rule drops TCP packets inbound on port 80. The rule specifies theinputchain in thefiltertable, and it drops (drop) all TCP traffic (tcp) destined for port 80 (dport 80), which means any incoming TCP traffic on port 80 will be dropped.

Option B (Incorrect):The command does not automatically update the configuration on disk; the rule is applied immediately in memory but does not persist across reboots unless explicitly saved.

Option C (Incorrect):The rule specifies TCP packets only, not all traffic. Therefore, it does not drop traffic for protocols other than TCP.

Option D (Incorrect):Although this statement is correct, it is less specific than Option A, which is more accurate because it mentions both IP versions.

Option F (Incorrect):The rule applies to inbound traffic, not outbound, so it does not drop outbound traffic.

Oracle Linux Reference:Refer to:

Oracle® Linux 8: Managing Firewall Rules with nftables

Option B: journalctl -p err shows only error log level.

Explanation:

The -p or --priority option in journalctl filters messages by their priority level.

When specifying asingle priority level, journalctl shows messagesonlyat that level.

The priority levels, as per syslog standards, are:

0: emerg

1: alert

2: crit

3: err

4: warning

5: notice

6: info

7: debug

Therefore, journalctl -p err displays messages with priorityerr (3)only.

Oracle Linux Reference:

Oracle® Linux 8: Managing Log Files- Section onFiltering Output withjournalctl:

"Use the -p option to display messages from the journal that have a specific priority level."

Example:

# journalctl -p err

Option D: journalctl -k shows kernel logs since the last boot.

Explanation:

The -k or --dmesg option filters messages from the kernel, equivalent to the output of the dmesg command.

This option implies -b, which limits the output to messages from the current boot.

Therefore, journalctl -k displays kernel messages since the last boot.

Oracle Linux Reference:

Oracle® Linux 8: Managing Log Files- Section onViewing Kernel Messages:

"Use the journalctl -k command to display kernel messages since the last system boot."

Example:

# journalctl -k

Option E: journalctl -p 6 shows all info log level messages and above.

Explanation:

When specifying a single numeric priority, journalctl displays messages withthat priority level and higher priority levels(i.e., lower severity).

Priority levels are ordered from 0 (highest severity) to 7 (lowest severity).

Therefore, journalctl -p 6 shows messages with priorities:

0 (emerg)

1 (alert)

2 (crit)

3 (err)

4 (warning)

5 (notice)

6 (info)

This includesinfo level messages (6)and all higher priority messages.

Oracle Linux Reference:

Oracle® Linux 8: Managing Log Files- Section onFiltering Output with journalctl:

"When you specify a single priority level, journalctl shows messages at that level and higher severity."

Example:

# journalctl -p 6

Why Other Options Are Not Correct:

Option A:journalctl -bl -p err fails if journal persistence is not configured.

Explanation:

The -b option displays messages from the current boot. This works even if journal persistence isnotconfigured because the logs from the current boot are stored in volatile memory (/run/log/journal).

Therefore, the command doesnot failif journal persistence is not configured.

Oracle Linux Reference:

Oracle® Linux 8: Managing Log Files- Section onJournal Volatility:

"By default, the journal stores logs in volatile memory and does not persist logs across reboots unless persistent storage is configured."

Option C:journalctl -p notice..warning shows all messages from notice to warning log level since the last boot.

Explanation:

The -p option allows specifying arangeof priorities. However, the correct order for the range should be from thehigher priority (lower number)to thelower priority (higher number).

Also, the priorities should be specified in the correct sequence, and ranges are inclusive.

Moreover, journalctl by default shows messages from all boots unless limited by the -b option.

Therefore, without -b, it does not limit messages to "since the last boot," making the statement incorrect.

Correct Command:

To display messages fromwarning (4)tonotice (5), the command should be:

# journalctl -p warning..notice -b

But even then, the priorities need to be specified correctly, and the command in Option C is incorrect.

Conclusion:

OptionsB,D, andEare correct because they accurately describe the behavior of the journalctl command in filtering and displaying log messages based on priority levels and sources.

Option C (Correct):If a device named/dev/hdbwith theide-diskdriver is discovered, a symbolic link/dev/sparediskwill be created, pointing to/dev/hdb.

Option D (Correct):TheKERNEL=="hdb"match specifies that the device will have the kernel device name/dev/hdb.

Option A (Incorrect):This is incorrect because existing symbolic links are not overwritten unless explicitly defined.

Option B (Incorrect):The device itself is not renamed to/dev/sparedisk; rather, a symbolic link is created.

Option E (Incorrect):The rule specifically requires bothKERNEL=="hdb"andDRIVER=="ide-disk"to match; it is not an either/or condition.

Explanation of Answer B:iostatis a tool used to monitor system input/output device loading by observing the time devices are active concerning their average transfer rates. The "Device Utilization Report" provides statistics about device utilization and throughput rates, which is critical in identifying performance bottlenecks.

Explanation of Answer E:iostatalso generates "CPU Utilization Reports." These reports provide data about how the CPU is utilized during input/output operations, showing the percentage of CPU time used for user processes, system processes, and the time the CPU remains idle.

Option D (Correct):Creating an empty file named.autorelabelin the root directory tells SELinux to relabel the entire file system during the next reboot.

Option F (Correct):Thefixfiles -F onbootcommand schedules a full file system relabel on the next reboot.

Option A, B, C, E (Incorrect):These options do not correctly set the system to relabel on reboot.

Oracle Linux Reference:Refer to:

Oracle® Linux 8: SELinux Guide