View Full LPI 202-450  Exam Dumps and Practice Test Dumps

 

Question 161. Which BIND directive specifies the IP addresses and ports on which named should listen for DNS queries?

1. allow-query
2. forwarders
3. recursion
4. listen-on

Correct Answer: 4. listen-on

Explanation :-

The BIND listen-on directive specifies the IPv4 addresses and ports on which the named daemon accepts DNS queries. It is useful on systems with multiple network interfaces when DNS service should be available only on selected addresses. allow-query controls which clients are permitted to query the server, while forwarders identifies other DNS servers to which queries can be forwarded. The recursion setting controls whether recursive resolution is available. Separating listening addresses from client authorization is important when securing and troubleshooting a BIND installation.

Question 162. Which HTTP status code indicates that a requested resource could not be found on the server?

1. 301
2. 404
3. 403
4. 500

Correct Answer: 2. 404

Explanation :-

HTTP status code 404 indicates that the requested resource could not be found. It commonly occurs when a URL points to a file or resource that does not exist at the requested location. A 403 response indicates that access to a resource is forbidden, while 301 indicates a permanent redirect and 500 indicates an internal server error. When troubleshooting Apache, administrators can examine the requested URL, DocumentRoot, rewrite rules, aliases, and error logs to determine why a legitimate resource is producing a 404 response.

Question 163. Which NFS option allows a client to continue retrying an operation until the NFS server becomes available again?

1. hard
2. noexec
3. ro
4. sync

Correct Answer: 1. hard

Explanation :-

The NFS hard mount option causes NFS client operations to continue retrying when the server becomes unavailable. This behavior can help protect data integrity because operations are not silently abandoned after a temporary network or server failure. In contrast, a soft mount can return an error after configured retries, although its use requires careful consideration because failed operations can have application-level consequences. Options such as ro control whether a filesystem is mounted read-only, while sync concerns synchronization behavior for export operations. Understanding NFS mount behavior is important when designing reliable network storage.

Question 164. Which Samba parameter restricts access to a share to a specified list of users or groups?

1. path
2. public
3. valid users
4. browseable

Correct Answer: 3. valid users

Explanation :-

The Samba valid users parameter specifies which users or groups are permitted to access a share. For example, an administrator can configure valid users = alice bob to restrict access to those accounts. The path parameter identifies the directory exported by the share, browseable controls whether the share appears in browse lists, and public is associated with guest accessibility. Access control can also involve filesystem permissions, ACLs, and authentication settings, so configuring valid users does not replace appropriate underlying Linux filesystem security.

Question 165. Which DNS record type is commonly used to publish arbitrary text such as SPF or domain-verification information?

1. TXT
2. PTR
3. NS
4. A

Correct Answer: 2. TXT

Explanation :-

TXT records allow domain administrators to publish arbitrary text data in DNS. They are commonly used for domain verification, SPF-related information, and other application-specific metadata. A records map names to IPv4 addresses, PTR records support reverse DNS, and NS records identify authoritative name servers. TXT records can contain multiple strings and are interpreted according to the application using them. Because DNS data is cached, changes to TXT records may not become visible everywhere immediately. Administrators should therefore consider TTL values and DNS propagation when modifying verification or email-related records.

Question 166. Which command displays the DNS servers currently configured for a Linux system using systemd-resolved?

1. ip route
2. resolvectl status
3. systemctl resolve
4. dig @local

Correct Answer: 4. resolvectl status

Explanation :-

The resolvectl status command provides information about the DNS configuration maintained by systemd-resolved. It can display global and per-link DNS servers, search domains, and other resolver information. This makes it useful for diagnosing name-resolution problems where network connectivity exists but hostnames cannot be resolved correctly. ip route displays routing information rather than DNS configuration. dig can query a DNS server and inspect its response, but it does not provide the same overview of the local systemd-resolved configuration. These tools complement each other during network troubleshooting.

Question 167. Which Postfix parameter specifies the hostname that Postfix uses to identify itself?

1. myhostname
2. mydestination
3. relay_domains
4. mynetworks

Correct Answer: 1. myhostname

Explanation :-

The Postfix myhostname parameter defines the system’s mail hostname as used by Postfix. It can influence the server’s identity in SMTP communication and is also used as a default in several related configuration settings. mydestination defines destinations for which the server is the final delivery system, while mynetworks identifies trusted networks and relay_domains defines domains for which the server is authorized to relay. Correctly setting myhostname is important for consistent mail-server identity, DNS configuration, and SMTP communication.

Question 168. Which Dovecot authentication database is primarily responsible for verifying user credentials?

1. passdb
2. mail_location
3. namespace
4. protocol

Correct Answer: 3. passdb

Explanation :-

In Dovecot, passdb defines the password database used to authenticate users. It may obtain credentials from files, system authentication mechanisms, SQL databases, LDAP, or other supported sources. The userdb configuration provides information about the user’s mailbox location and related account details. mail_location specifies mailbox storage, while namespace and protocol settings define other aspects of Dovecot’s mail service configuration. Understanding the separation between authentication data and user mailbox information is important when troubleshooting login failures and configuring Dovecot for different authentication backends.

Question 169. Which SSH configuration option disables direct root login over SSH?

1. AllowUsers
2. PasswordAuthentication
3. PermitRootLogin
4. PubkeyAuthentication

Correct Answer: 4. PermitRootLogin

Explanation :-

The OpenSSH PermitRootLogin directive controls whether the root account can log in directly through SSH and under which authentication conditions. Setting it to no disables direct root login. Other values can permit restricted forms of root authentication depending on the OpenSSH version and configuration. PasswordAuthentication controls password-based authentication for users generally, PubkeyAuthentication controls public-key authentication, and AllowUsers restricts which user accounts may connect. Administrators should make SSH configuration changes carefully and validate them before reloading the service, particularly on remote systems.

Question 170. Which SELinux command changes the enforcement mode temporarily without changing the persistent configuration?

1. semanage boolean
2. restorecon
3. chcon
4. setenforce

Correct Answer: 2. setenforce

Explanation :-

The setenforce command changes SELinux between enforcing and permissive modes at runtime. For example, setenforce 0 places SELinux into permissive mode, while setenforce 1 returns it to enforcing mode. This change is temporary and does not permanently modify the SELinux configuration that determines the mode after reboot. restorecon restores file security contexts, chcon changes a context directly, and semanage manages persistent SELinux policy-related settings. Temporarily changing enforcement can assist troubleshooting, but administrators should investigate and correct the underlying policy issue rather than treating permissive mode as a permanent solution.

Question 171. Which nftables command displays the rules contained in a specific table?

1. nft list table inet filter
2. nft show table inet filter
3. nft table list inet filter
4. nft -T inet filter

Correct Answer: 1. nft list table inet filter

Explanation :-

The command nft list table inet filter displays the contents of the specified inet family table named filter. The output can include chains, rules, sets, and other objects associated with that table. nft list ruleset can instead display the complete loaded nftables ruleset across tables. Inspecting a particular table is useful when troubleshooting firewall behavior without having to review unrelated configurations. Administrators should know the nftables hierarchy of families, tables, chains, rules, sets, and hooks because these components determine how packet filtering and related processing are organized.

Question 172. Which DNS record type specifies a service location, including a target hostname and port?

1. SOA
2. SRV
3. CNAME
4. AAAA

Correct Answer: 3. SRV

Explanation :-

SRV records specify the location of services by providing information such as priority, weight, port, and target hostname. They allow applications to discover the appropriate server and port for a named service without relying solely on a fixed hostname or default port. SOA records describe zone authority and administrative timing information, CNAME records provide aliases, and AAAA records map names to IPv6 addresses. SRV records are used by several network applications and are an important part of DNS service discovery. Administrators should verify both the record syntax and the target host when troubleshooting service discovery.

Question 173. Which Apache directive creates a permanent HTTP redirect to another URL?

1. Redirect
2. ProxyPass
3. Alias
4. RedirectPermanent

Correct Answer: 4. RedirectPermanent

Explanation :-

The Apache RedirectPermanent directive creates a permanent HTTP redirect, normally resulting in an HTTP 301 response. It can be used when a resource has permanently moved to another URL and clients should use the new location. The Redirect directive can also perform redirects but may use a different status depending on its configuration. Alias maps URL paths to filesystem locations, while ProxyPass is used for reverse-proxy mappings. Correct redirect configuration is important when migrating websites because permanent redirects help clients and search systems recognize that a resource has moved.

Question 174. Which NFS utility displays statistics about NFS client and server operations?

1. showmount
2. exportfs
3. nfsstat
4. mount.nfs

Correct Answer: 1. nfsstat

Explanation :-

The nfsstat utility displays statistics about NFS activity, including client and server operations, depending on the platform and options used. It can help administrators identify unusual request patterns, retransmissions, or other NFS-related behavior. showmount queries export information, exportfs manages server exports, and mount.nfs is used to mount NFS filesystems. NFS troubleshooting often requires examining both client-side and server-side information, including network connectivity, RPC services, mount options, export permissions, and filesystem performance.

Question 175. Which SMTP protocol command specifies the sender’s email address during an SMTP transaction?

1. RCPT TO
2. HELO
3. DATA
4. MAIL FROM

Correct Answer: 2. MAIL FROM

Explanation :-

The SMTP MAIL FROM command specifies the envelope sender during an SMTP transaction. It is normally followed by one or more RCPT TO commands identifying recipients and then a DATA command to transmit the message content. HELO or EHLO identifies the client and begins SMTP negotiation. The envelope sender is distinct from headers such as the visible From field in the message itself. Understanding SMTP command order is useful when diagnosing mail delivery problems, interpreting SMTP logs, and troubleshooting Postfix communication with remote mail servers.

Question 176. Which command can be used to display the current network interfaces and their assigned IP addresses?

1. ip addr
2. ip route
3. ip neigh
4. ss -r

Correct Answer: 3. ip addr

Explanation :-

The ip addr command displays network interfaces and their assigned IP addresses, along with information such as interface state and address scope. It is one of the primary tools used to inspect Linux network configuration. ip route displays routing information, while ip neigh displays the neighbor table used for local network address resolution. The ss utility provides socket information. When troubleshooting network client connectivity, administrators commonly inspect ip addr, ip route, DNS configuration, and interface state together to identify whether the problem is local addressing, routing, or name resolution.

Question 177. Which BIND command validates the syntax of the main named configuration file?

1. named-checkzone
2. rndc checkconf
3. named-checkconf
4. dig -check

Correct Answer: 1. named-checkconf

Explanation :-

The named-checkconf utility validates the syntax of BIND’s main configuration file, normally /etc/named.conf or a distribution-specific equivalent. It can help identify configuration errors before the administrator attempts to reload the DNS service. named-checkzone is intended for validating individual zone files, while rndc is used to communicate with a running BIND server. dig performs DNS queries and does not validate BIND configuration syntax. Using the appropriate validation utility before applying configuration changes can reduce service disruption caused by malformed DNS configuration.

Question 178. Which Apache HTTP status code indicates that the server understood the request but refuses to authorize access to the requested resource?

1. 301
2. 403
3. 404
4. 503

Correct Answer: 4. 403

Explanation :-

HTTP status code 403 indicates that the server understood the request but refuses to authorize access to the requested resource. In Apache, a 403 response can result from filesystem permissions, authorization directives, access-control rules, or configuration restrictions. A 404 indicates that the requested resource could not be found, while 301 indicates a permanent redirect and 503 indicates that the service is temporarily unavailable. When troubleshooting a 403 response, administrators should inspect Apache authorization configuration, filesystem permissions, SELinux contexts, and relevant error-log entries.

Question 179. Which command is commonly used to list the Samba shares currently connected to a server and associated sessions?

1. testparm
2. smbclient
3. smbstatus
4. smbpasswd

Correct Answer: 3. smbstatus

Explanation :-

The smbstatus utility displays information about active Samba connections, sessions, locks, and related server activity. It is useful when an administrator needs to determine which clients are connected to a Samba server and which resources are being accessed. testparm validates Samba configuration, smbclient provides an SMB client interface, and smbpasswd manages Samba password information. Samba troubleshooting often involves combining smbstatus with configuration validation, filesystem permission checks, and client-side connection testing.

Question 180. Which SSH feature allows a client to access another host through an intermediate SSH server using the client’s forwarded authentication agent?

1. X11 forwarding
2. Local port forwarding
3. Dynamic forwarding
4. Agent forwarding

Correct Answer: 2. Agent forwarding

Explanation :-

SSH agent forwarding allows an SSH client to use an authentication agent running on the local system when connecting through an intermediate SSH server. The private keys remain on the original client, while the remote SSH session can request signatures from the forwarded agent. This can be useful when an administrator needs to connect from one remote system to another without copying private keys onto intermediate hosts. Agent forwarding should be enabled carefully because a compromised intermediate host may potentially use the forwarded agent during the active session. It is distinct from X11 and network port forwarding.