LPIC-2 Practice Questions 1 — 50 Questions

Question 1

Which of the following is the primary configuration file for the udev device manager?

Accepted Answer

/etc/udev/udev.conf. The primary configuration file for the udev device manager is /etc/udev/udev.conf. This file sets global parameters such as the device timeout, logging priority, and the default permissions for device nodes. While custom rules are placed in /etc/udev/rules.d/, the main configuration file that controls udev's behavior is udev.conf.

Answer

/etc/udev/rules.d/

Answer

/lib/udev/rules.d/

Answer

/etc/udev/rules.d/

Question 2

A system's root filesystem on /dev/sda1 is offline. The administrator boots into rescue mode and needs to check the filesystem integrity. Which command should be used first?

Accepted Answer

e2fsck -p /dev/sda1. `e2fsck -p` runs an automatic, non-interactive filesystem check on the ext2/ext3/ext4 filesystem, which is the safest first step when the root filesystem is offline and the administrator is in rescue mode. The `-p` flag automatically repairs any problems that can be safely fixed without user intervention, minimizing risk of further damage. This command is specifically designed for ext-family filesystems and is the recommended initial integrity check before attempting any manual repairs.

Answer

dumpe2fs /dev/sda1

Answer

fsck.ext4 -f /dev/sda1

Answer

fsck -N /dev/sda1

Question 3

Which sysctl parameter controls the system's behavior when a kernel oops occurs (e.g., automatically reboot)?

Accepted Answer

kernel.panic_on_oops. The `kernel.panic_on_oops` sysctl parameter controls the system's behavior when a kernel oops occurs. Setting it to 1 causes the kernel to panic on an oops, and if `kernel.panic` is also set to a positive value (e.g., seconds before reboot), the system will automatically reboot after the panic. This is the correct parameter for triggering a reboot on an oops.

Answer

vm.panic_on_oom

Answer

kernel.unknown_nmi_panic

Answer

kernel.oops

Question 4

Which TWO of the following commands can be used to list currently loaded kernel modules? (Choose two.)

Accepted Answer

cat /proc/modules. `/proc/modules` is a virtual file maintained by the kernel that lists all currently loaded kernel modules, including their size, usage count, and dependent modules. Reading this file provides a real-time snapshot of the kernel's module state. Option E is correct because `lsmod` is a user-space utility that parses `/proc/modules` and formats the output in a human-readable table, making it the standard command for listing loaded modules.

Answer

modinfo -l

Answer

ls /lib/modules/$(uname -r)

Answer

depmod -e

Question 5

Refer to the exhibit. Which kernel version will be booted by default when using a standard GRUB2 configuration that uses the symlinks vmlinuz and initrd.img?

Accepted Answer

5.10.0-9-amd64. In a standard GRUB2 configuration, the symlinks `vmlinuz` and `initrd.img` point to the latest installed kernel version. When GRUB2 generates its boot menu using `update-grub` (or `grub-mkconfig`), it reads these symlinks to create the default boot entry. Therefore, the default booted kernel is the one pointed to by these symlinks, which in this case is 5.10.0-9-amd64.

Answer

Depends on GRUB_DEFAULT setting, but if not set, it will boot the highest versioned kernel

Answer

It will prompt to choose between the two kernels

Answer

5.10.0-8-amd64

Question 6

A company uses BIND9 as the authoritative name server for its public zone example.com. External users report that they cannot resolve the MX record for the domain, but internal users can. What is the most likely cause?

Accepted Answer

The allow-query ACL restricts queries to the internal network.. The allow-query ACL in BIND9 restricts which source IP addresses are permitted to send queries to the server. If it is set to allow only the internal network (e.g., 192.168.0.0/16), external users' queries are rejected, causing resolution failures for MX records and all other records. Internal users succeed because their IPs match the ACL, while external users receive a REFUSED response or no answer.

Answer

The zone file lacks an MX record.

Answer

The server is behind a firewall that blocks UDP port 53.

Answer

The recursion is set to no.

Question 7

Which TWO parameters in the [global] section are REQUIRED for a Samba server to act as a standalone server (not a member of a domain)?

Accepted Answer

workgroup. For a Samba standalone server, the `workgroup` parameter defines the NetBIOS workgroup name that the server will appear in, which is essential for browsing and identification on the local network. The `security = user` parameter is required because it sets the server to authenticate users locally against its own passdb backend, rather than relying on an external domain controller. Without these two, the server cannot function as a standalone unit.

Answer

server string

Answer

netbios name

Answer

passdb backend = tdbsam

Question 8

Which file is used to configure the LDAP client for system authentication on a modern Linux system using nss-pam-ldapd?

Accepted Answer

/etc/nslcd.conf. /etc/nslcd.conf is the configuration file for nslcd, the LDAP name service daemon used by nss-pam-ldapd to perform LDAP queries for system authentication and user/group lookups. This daemon communicates with the LDAP server and provides the results to NSS and PAM modules, making it the central configuration point for LDAP client authentication on modern Linux systems.

Answer

/etc/openldap/ldap.conf

Answer

/etc/nsswitch.conf

Answer

/etc/ldap.conf

Question 9

An administrator configures a Samba share with guest access. After testing, guests are prompted for a password. Which directive should be added to the [global] section to allow guest access without a password?

Accepted Answer

map to guest = Bad User. The 'map to guest = Bad User' directive in the [global] section tells Samba to automatically map any login attempt with an invalid username to the guest account, bypassing password authentication. This is the correct setting to allow guest access without a password prompt, as it treats unknown users as guests.

Answer

guest account = nobody

Answer

security = user

Answer

encrypt passwords = yes

Question 10

Which THREE of the following actions are recommended as initial security hardening steps after installing a new Linux server? (Choose three.)

Accepted Answer

Update all packages using the package manager.. Immediately updating all packages via the package manager (e.g., `apt upgrade` or `yum update`) applies the latest security patches to the kernel, libraries, and services, closing known vulnerabilities that could be exploited by attackers. This is a foundational step in the initial hardening process, as a newly installed system often ships with outdated packages that have published CVEs.

Answer

Install a graphical desktop environment for easier administration.

Answer

Set up a web server to monitor system status.

Question 11

Refer to the exhibit. A user in the group 'staff' attempts to access the share 'share' from a Windows client. The user is prompted for credentials and authenticates successfully, but cannot write any files. What is the most likely reason?

Accepted Answer

The share has read only = Yes, which prevents writes even for authenticated users.. The `read only = Yes` parameter in a Samba share definition explicitly prevents all write operations, even for authenticated users. When this parameter is set, Samba enforces read-only access at the share level, overriding any user or group permissions that might otherwise allow writes. Since the user authenticates successfully but cannot write, the most direct cause is this share-level restriction.

Answer

The passdb backend is set to tdbsam, which does not support write operations.

Answer

The share has guest ok = No, which prevents guest access.

Answer

The valid users parameter does not include the user.

Question 12

An administrator configures iptables on a Linux firewall with the following rules: -A INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT; -A INPUT -p tcp --dport 22 -m state --state ESTABLISHED,RELATED -j ACCEPT; -A INPUT -j DROP. Users report that SSH connections are being dropped. What is the most likely cause?

Accepted Answer

The SSH rule should have -m state --state NEW to allow new connections.. The most likely cause is that the SSH rule only matches packets that are already part of an established or related connection. New SSH connections start with a SYN packet that is in the NEW state, so they are not matched by the second rule. They fall through to the final DROP rule and are dropped. Adding `-m state --state NEW` (or `-m state --state NEW,ESTABLISHED,RELATED`) to the SSH rule would allow new connections. Option A is incorrect because the default INPUT policy is not relevant when explicit DROP exists; B confuses source and destination ports; D is wrong because reordering does not change the state matching logic.

Answer

The default INPUT policy is DROP, so the last rule is redundant but harmless.

Answer

The rule for SSH uses --dport 22, but the source port is randomized; it should use --sport 22.

Answer

The established/related rule should come after the SSH rule.

Question 13

A firewall rule set is implemented using iptables. The administrator wants to allow incoming SSH connections only from the 192.168.1.0/24 subnet, while all other incoming traffic is dropped. Which set of rules achieves this?

Accepted Answer

iptables -A INPUT -p tcp --dport 22 -s 192.168.1.0/24 -j ACCEPT
iptables -A INPUT -j DROP. It first adds a rule to accept TCP traffic on port 22 (SSH) from the 192.168.1.0/24 subnet, then adds a default DROP rule for all other incoming traffic. Since iptables processes rules in order, the ACCEPT rule matches allowed SSH connections first, and the subsequent DROP rule catches all other incoming packets, effectively dropping everything else including SSH from other sources.

Answer

iptables -A INPUT -p tcp --sport 22 -s 192.168.1.0/24 -j ACCEPT
iptables -A INPUT -j DROP

Answer

iptables -A INPUT -p tcp --dport 22 -j DROP
iptables -A INPUT -s 192.168.1.0/24 -p tcp --dport 22 -j ACCEPT

Answer

iptables -A INPUT -p tcp --dport 22 -j ACCEPT
iptables -A INPUT -p tcp --dport 22 -s 192.168.1.0/24 -j DROP

Answer

iptables -A INPUT -p tcp --dport 22 -j ACCEPT
iptables -A INPUT -j DROP

Question 14

Which TWO commands can be used to list all currently listening TCP ports and the associated processes?

Accepted Answer

ss -tlnp. (ss -tlnp) is correct because the ss command with -t (TCP), -l (listening), -n (numeric), and -p (process) shows all listening TCP ports and their associated processes. Option C (netstat -tlnp) is correct because netstat with the same flags provides equivalent output, though ss is the modern replacement on many distributions.

Answer

lsof -i TCP -s TCP:LISTEN

Answer

fuser -v 80/tcp

Answer

nmap -sT localhost

Question 15

In Samba 4, what is the default security mode when no 'security' parameter is set in the [global] section?

Accepted Answer

user. In Samba 4, when no 'security' parameter is explicitly set in the [global] section, the default security mode is 'user'. This means clients must authenticate with a valid username and password, and Samba validates credentials against the local passdb backend (e.g., tdbsam or LDAP). This default has been consistent since Samba 3.x and ensures that each connection is tied to a specific user identity.

Answer

ads

Answer

share

Answer

domain

Question 16

A company wants to host multiple websites on a single Apache server with different domain names. Which approach is most appropriate?

Accepted Answer

Name-based virtual hosting. Name-based virtual hosting allows a single Apache server to serve multiple websites using the same IP address and port by relying on the HTTP Host header sent by the client. This is the most efficient and commonly used method for hosting multiple domains on one server, as it conserves IP addresses and requires minimal configuration via the `<VirtualHost *:80>` directive.

Answer

IP-based virtual hosting

Answer

Port-based virtual hosting

Answer

Using mod_rewrite for each domain

Question 17

Based on the smbstatus output, which statement is true?

Accepted Answer

User 'alice' connected from IP 192.168.1.10 using SMB3 protocol. The smbstatus output shows that user 'alice' is connected from IP address 192.168.1.10 and the 'Protocol' column explicitly lists 'SMB3_11', which is a variant of the SMB3 protocol. This directly matches the statement in option A that alice is using SMB3 protocol.

Answer

Both users are using SMB2 protocol

Answer

User 'bob' is accessing share2 with write permissions

Answer

User 'alice' has an exclusive lock on report.pdf

Question 18

A system with SELinux in enforcing mode is running a custom application that needs to write to a file in /data. The application's context type is 'myapp_t', and the target file context is 'default_t'. The file's current context is 'var_t'. Which command changes the file's context to allow access?

Accepted Answer

chcon -t default_t /data/file. `chcon -t default_t /data/file` directly changes the SELinux type of the file to `default_t`, which matches the type expected by the `myapp_t` domain's access rules. Since the application runs in enforcing mode and needs to write to a file with type `default_t`, this command immediately sets the correct context without modifying the policy or requiring a relabel.

Answer

fixfiles -F relabel /data

Answer

semanage fcontext -a -t default_t /data/file

Answer

restorecon /data/file

Question 19

Refer to the exhibit. The /data filesystem is nearly full. The administrator has added a new disk /dev/sdc with 10GB capacity. The VG currently has no free space. Which steps will increase the available space for /data using LVM and ext4?

Accepted Answer

pvcreate /dev/sdc; vgextend vg /dev/sdc; lvextend -l +100%FREE /dev/vg/data; resize2fs /dev/vg/data. It follows the proper LVM workflow: create a physical volume (pvcreate), add it to the volume group (vgextend), extend the logical volume using all free space in the VG (lvextend -l +100%FREE), and then resize the ext4 filesystem (resize2fs). This ensures the new 10GB disk is fully utilized for /data.

Answer

vgextend vg /dev/sdc; lvextend -L +10G /dev/vg/data; resize2fs /dev/vg/data

Answer

pvcreate /dev/sdc; lvextend -L +10G /dev/vg/data; resize2fs /dev/vg/data

Answer

pvcreate /dev/sdc; vgextend vg /dev/sdc; lvextend -l +50%FREE /dev/vg/data; resize2fs /dev/vg/data

Question 20

Which command will display the current VLAN membership of interface eth1?

Accepted Answer

bridge vlan show dev eth1. The `bridge vlan show dev eth1` command displays the current VLAN membership of a specific interface when the interface is part of a Linux bridge. This command queries the kernel's bridge VLAN filtering database, showing which VLAN IDs are tagged or untagged on the given port, which is the standard way to view VLAN membership in modern Linux networking.

Answer

vconfig list eth1

Answer

ip addr show eth1

Answer

cat /proc/net/vlan/eth1

Answer

ip link show eth1