LPIC-2 Practice Exam 2 — 20 Questions

Question 1

Refer to the exhibit. What is the effect of this sudoers configuration?

Accepted Answer

Users alice and bob can run apt-get and dpkg on any host as root, requiring a password.. The sudoers configuration specifies that users alice and bob are allowed to run only the commands /usr/bin/apt-get and /usr/bin/dpkg as root on any host (ALL). The absence of the NOPASSWD tag means that a password is required for these commands. The syntax 'alice,bob ALL=(root) /usr/bin/apt-get, /usr/bin/dpkg' restricts the command set and requires authentication.

Answer

Users alice and bob can run any software command on the localhost only.

Answer

Members of ADMINS can run any command as root on any host.

Answer

Users alice and bob can run apt-get and dpkg without a password.

Question 2

A Samba share is intended for guest (anonymous) access. Which global parameter must be set to allow this?

Accepted Answer

map to guest = Bad User. The `map to guest = Bad User` parameter in Samba's global configuration forces any connection attempt with an invalid or non-existent username to be treated as a guest (anonymous) login. This is the standard way to allow anonymous access to shares while still using `security = user` (the default in modern Samba), as it maps failed authentication to the guest account.

Answer

guest account = nobody

Answer

security = share

Answer

security = user

Question 3

A Linux system administrator is tasked with upgrading the kernel on a server running a custom compiled kernel (version 4.19) with many in-house modules. The new kernel (5.10) has significant changes, including a different API for some module functions. After compiling the new kernel and the modules, the system boots but some modules fail to load with 'Unknown symbol' errors. The administrator needs to identify which symbols are missing and fix the modules. Which of the following is the most effective approach?

Accepted Answer

Run 'modprobe --dump-modversions mymodule.ko' and compare with 'cat /proc/kallsyms' to identify mismatches. `modprobe --dump-modversions mymodule.ko` displays the symbol version (CRC) checksums for each symbol the module uses, and comparing these with `/proc/kallsyms` (which lists all symbols exported by the running kernel along with their CRC values) directly pinpoints which symbols have mismatched versions. This is the most efficient method to identify 'Unknown symbol' errors caused by API changes between kernel 4.19 and 5.10, as it reveals exactly which symbols need updating in the module source code.

Answer

Check dmesg for each module load error and recompile modules one by one

Answer

Rename the missing symbols in the source code to match the new kernel's exported symbols

Answer

Use 'nm mymodule.ko' to list all symbols and manually compare with the kernel's symbol table

Question 4

An administrator notices that an NFS mount on a client becomes unresponsive when the NFS server goes offline. The admin wants the mount to return an error to the application after a short timeout instead of hanging indefinitely. Which mount option should be added to the fstab entry?

Accepted Answer

soft. The `soft` mount option causes the NFS client to return an error to the application after a short timeout (typically 60 seconds by default) if the NFS server becomes unresponsive, rather than hanging indefinitely. This is the correct choice because the administrator specifically wants the mount to return an error after a short timeout instead of hanging.

Answer

intr

Answer

bg

Answer

hard

Question 5

A Linux client is configured with the following in /etc/nslcd.conf: 'uri ldap://10.0.0.1/', 'base dc=example,dc=com'. Which command can be used to test connectivity to the LDAP server and verify the base DN?

Accepted Answer

ldapsearch -x -H ldap://10.0.0.1 -b dc=example,dc=com. The `ldapsearch` command with `-x` (simple authentication), `-H ldap://10.0.0.1` (specifying the LDAP URI), and `-b dc=example,dc=com` (setting the search base DN) directly performs an anonymous LDAP search against the server. If the server is reachable and the base DN exists, it returns entries, confirming both connectivity and the validity of the base DN. This matches the configuration in `/etc/nslcd.conf` and is the standard tool for testing LDAP server responses.

Answer

authconfig --test

Answer

getent passwd

Answer

nslcd -d

Question 6

Which command is used to list the NFS exports available from a specific server?

Accepted Answer

showmount -e server. The `showmount -e server` command queries the NFS server's mount daemon (rpc.mountd) to list the exported filesystems that are currently available. This is the standard method for a client to discover which NFS shares a server is offering, as it directly interrogates the server's export list via the RPC protocol.

Answer

mount -t nfs4 server:/export /mnt

Answer

nfsstat

Answer

exportfs -a

Question 7

A Samba server is configured with 'security = ads' and joined to an Active Directory domain. Users can authenticate but cannot access shares. The smb.conf includes 'winbind use default domain = yes'. What could be the problem?

Accepted Answer

The 'valid users' parameter uses domain prefix while default domain is set. When 'winbind use default domain = yes' is set, Winbind strips the domain prefix from usernames, so users authenticate as 'username' instead of 'DOMAIN\username'. If the 'valid users' parameter in a share definition explicitly uses the domain prefix (e.g., 'valid users = DOMAIN\username'), the stripped username will not match, and access is denied. This mismatch is the most direct cause of authentication succeeding but share access failing.

Answer

The 'winbind use default domain' option should be 'no'

Answer

The 'idmap backend' is not configured

Answer

The Samba server's time is not synchronized with the domain controller

Question 8

A Samba server experiences slow file transfers for large files. The administrator suspects oplock issues. Which set of parameters should be adjusted to disable opportunistic locking?

Accepted Answer

oplocks = no and level2 oplocks = no. Disabling opportunistic locking (oplocks) in Samba requires setting both 'oplocks = no' and 'level2 oplocks = no'. The 'oplocks = no' directive disables exclusive oplocks, but Samba's default behavior still allows level2 oplocks (read-only caching). To fully disable all forms of oplock caching, both parameters must be set to 'no', preventing client-side caching that can cause conflicts and slow transfers for large files.

Answer

oplocks = false alone is sufficient

Answer

strict locking = yes

Answer

kernel oplocks = no

Question 9

Refer to the exhibit. What is the most likely cause of this Apache error?

Accepted Answer

The semaphore limit for the Apache user is exceeded.. The Apache error 'semaphore limit exceeded' occurs when the number of semaphores allocated to the Apache user exceeds the system-wide or per-user semaphore limit. Apache uses semaphores for inter-process communication (IPC) in its prefork or worker MPMs to coordinate child processes. The correct answer is C because this error directly indicates that the kernel's semaphore limits (e.g., `SEMMSL`, `SEMMNS`, or `SEMOPM` in `/proc/sys/kernel/sem`) have been exhausted for the Apache user, often due to too many child processes or a misconfigured `MaxClients` directive.

Answer

The filesystem containing the logs is full.

Answer

The server is out of memory.

Answer

The RewriteMap file specified is missing.

Question 10

A database server experiences performance degradation. Analysis shows high I/O wait on a LVM logical volume that uses striping across two physical volumes. What is the most effective way to improve performance?

Accepted Answer

Add a cache layer using lvmcache on a fast SSD. Adding a cache layer using lvmcache on a fast SSD is the most effective way to reduce high I/O wait because it places frequently accessed (hot) data on the faster SSD while keeping the bulk of data on the slower striped HDDs. This directly addresses the I/O bottleneck without requiring data migration or downtime, and it leverages the existing striped layout for sequential throughput while improving latency for random reads/writes.

Answer

Increase the stripe size and recreate the LV

Answer

Add an additional PV to the VG and extend the LV

Answer

Convert the LV to use linear mapping instead of striping

Question 11

An administrator wants to drop incoming TCP packets on port 22 from IP 10.0.0.5 using iptables. Which command is correct?

Accepted Answer

iptables -A INPUT -s 10.0.0.5 -p tcp --dport 22 -j DROP. It adds a rule to the INPUT chain, which processes packets destined for the local system. The `-s 10.0.0.5` flag specifies the source IP address, `-p tcp --dport 22` matches TCP packets destined for port 22 (SSH), and `-j DROP` silently discards matching packets. This configuration drops incoming SSH traffic from the specified host before it reaches any local service.

Answer

iptables -A INPUT -d 10.0.0.5 -p tcp --dport 22 -j DROP

Answer

iptables -A FORWARD -s 10.0.0.5 -p tcp --dport 22 -j DROP

Answer

iptables -A OUTPUT -s 10.0.0.5 -p tcp --dport 22 -j DROP

Question 12

Which two commands can be used to create a swap space on a partition /dev/sdb2? (Choose two.)

Accepted Answer

mkswap /dev/sdb2. The `mkswap` command initializes a partition or file for use as swap space by writing a swap signature (UUID and superblock) to the device. Option A is correct because `mkswap /dev/sdb2` creates the swap filesystem on the specified partition. Option D is also correct because `mkswap -L swap /dev/sdb2` does the same but additionally assigns a label 'swap' to the swap area, which is a valid variant of the command.

Answer

swapon /dev/sdb2

Answer

dd if=/dev/zero of=/dev/sdb2 bs=1M count=1024

Answer

mkfs.swap /dev/sdb2

Question 13

Which TWO global parameters can be used to control the security mode of a Samba server?

Accepted Answer

security. The `security` parameter is the primary global setting that defines the Samba server's security mode (e.g., user, domain, ads, server). The `map to guest` parameter controls how Samba handles authentication failures by optionally mapping invalid users to the guest account, effectively modifying the security behavior. Both are global parameters that directly influence the security mode of the Samba server.

Answer

netbios name

Answer

workgroup

Answer

server string

Question 14

A system administrator recently configured two NICs in a bonding interface (bond0) using mode 1 (active-backup). Although both links appear up, traffic never fails over when the primary link goes down. Which command should the administrator use to diagnose the bonding status and determine the root cause?

Accepted Answer

cat /proc/net/bonding/bond0. /proc/net/bonding/bond0 is the kernel-level interface that exposes the current bonding driver state, including active slave, link status, and failover counters. In mode 1 (active-backup), this file shows whether the primary interface is actually marked as 'up' by the bonding driver and whether the backup interface is ready to take over. The administrator can check for issues such as the primary link being stuck in a 'down' state due to misconfigured MII monitoring or missing 'miimon' parameter.

Answer

netstat -i

Answer

ifconfig bond0

Answer

ethtool bond0

Question 15

A system administrator wants to ensure that all commands executed by root are logged to a remote syslog server. Which rsyslog configuration directive should be used?

Accepted Answer

authpriv.* @192.168.1.100. The `authpriv` facility in rsyslog is specifically designated for security and authorization messages, including all commands executed by root via `sudo` or direct login. The directive `authpriv.* @192.168.1.100` sends all messages from this facility to the remote syslog server at UDP port 514. This matches the requirement to log root's commands, as Linux systems typically log such events under the `authpriv` facility.

Answer

auth.* @192.168.1.100

Answer

user.* @192.168.1.100

Answer

kern.* @192.168.1.100

Question 16

Which three PAM modules can be used to enforce password complexity? (Select three.)

Accepted Answer

pam_passwdqc.so. pam_passwdqc.so, pam_pwquality.so, and pam_cracklib.so are all PAM modules specifically designed to enforce password complexity policies, such as requiring a mix of character types, minimum length, or rejecting weak passwords. pam_passwdqc.so uses a configurable password quality checking framework, pam_pwquality.so (the successor to pam_cracklib.so) provides similar checks via the libpwquality library, and pam_cracklib.so (the original module) performs dictionary checks and complexity rules. These modules are typically stacked in the password authentication stack to validate new passwords against defined policies.

Answer

pam_securetty.so

Answer

pam_unix.so

Question 17

An administrator configures an NIS client by running 'ypbind' and updating /etc/nsswitch.conf to include 'nis' for passwd, shadow, and group. However, 'getent passwd' still shows only local users. Which step is most likely missing?

Accepted Answer

Edit /etc/yp.conf to specify the NIS server's domain and address.. The NIS client must know which NIS server to contact for domain information. This is configured in /etc/yp.conf, which specifies the NIS domain name and the server's hostname or IP address. Without this file, ypbind cannot locate a server, so getent falls back to local sources despite nsswitch.conf listing 'nis'.

Answer

Restart the ypserv service on the client.

Answer

Execute 'yppasswd' to initialize NIS client.

Answer

Run 'make -C /var/yp' on the client.

Question 18

A Samba share is configured with 'browseable = yes' but Windows clients cannot see it in the network list. However, they can access it by typing the UNC path directly. Which parameter is most likely misconfigured?

Accepted Answer

local master. The 'local master' parameter controls whether the Samba server participates in the election for the local master browser on the subnet. If set to 'no', the Samba server will not become the master browser, and Windows clients rely on the master browser to populate the network list. Since clients can access the share via UNC path but not see it in the network list, the browsing service is failing, which is directly tied to the local master setting.

Answer

os level

Answer

netbios name

Answer

server string

Question 19

A Linux router running multiple routing tables is misconfigured. The administrator wants to add a policy routing rule that sends all traffic from subnet 10.10.0.0/16 to routing table 200. Which command should be used?

Accepted Answer

ip rule add from 10.10.0.0/16 table 200. The `ip rule` command is used to add policy routing rules in Linux, which direct packets to specific routing tables based on criteria like source address. The `from` parameter specifies the source subnet (10.10.0.0/16), and `table 200` directs matching traffic to routing table 200, enabling policy-based routing beyond the default table.

Answer

route add -net 10.10.0.0/16 table 200

Answer

iptables -A FORWARD -s 10.10.0.0/16 -j table 200

Answer

ip route add 10.10.0.0/16 dev eth0 table 200

Question 20

A company's file server uses NFS to export /data to clients. An administrator configures an NFS client by running 'mount -t nfs fileserver:/data /mnt/data'. The mount succeeds and the user can read files. However, after a network interruption, the client system becomes unresponsive when a user attempts to access /mnt/data. Which action should the administrator take to prevent this issue in the future?

Accepted Answer

Add the 'soft' option to the mount command: 'mount -t nfs -o soft fileserver:/data /mnt/data'.. Using a 'soft' mount causes NFS operations to return an error to the calling application after a timeout, rather than hanging indefinitely. This prevents the client system from becoming unresponsive when the NFS server is unreachable, as the kernel will not retry the request forever. The default 'hard' mount (used in the original command) will keep retrying until the server responds, which can block processes and make the system appear frozen.

Answer

Add the 'intr' mount option to allow signal interrupts.

Answer

Increase the timeout value with 'timeo=600' and keep the hard mount.

Answer

Use the 'noac' option to disable attribute caching.