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

 

Question 261. Which BIND utility verifies the syntax of a DNS zone file?

1. rndc-checkzone
2. named-checkzone
3. named-checkconf
4. dnscheck

Correct Answer: 2. named-checkzone

Explanation :-

The named-checkzone utility validates the syntax and integrity of a BIND zone file. It normally requires the zone name and the path to the zone file, for example, named-checkzone example.com /var/named/example.com.zone. This helps administrators detect syntax errors before reloading the DNS service. named-checkconf instead validates the BIND configuration file, while rndc is used to control a running BIND server. Checking zone files before deployment is an important DNS administration practice because malformed records can prevent a zone from loading correctly.

Question 262. Which Apache directive defines the hostname that the server uses to identify itself?

1. ServerAlias
2. HostName
3. ListenName
4. ServerName

Correct Answer: 4. ServerName

Explanation :-

The Apache ServerName directive specifies the hostname and optionally the port that the server uses to identify itself. It is commonly configured inside a virtual host definition and is important when Apache serves multiple sites. ServerAlias defines additional hostnames that should match the same virtual host. Listen controls the network address and port on which Apache accepts connections, rather than defining the server’s hostname. Correct ServerName configuration can also help avoid startup warnings and ensures that virtual-host matching behaves as intended.

Question 263. Which NFS mount option prevents clients from modifying files on the exported file system?

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

Correct Answer: 1. ro

Explanation :-

The NFS ro mount option mounts an exported file system as read-only from the client. This prevents normal write operations through that mount point. It can be useful when clients need access to shared reference data without being allowed to modify it. The sync option controls synchronization behavior, noexec prevents execution of binaries from the mounted file system, and hard controls how NFS requests behave when the server becomes unavailable. Read-only access can also be enforced on the server through the corresponding export configuration.

Question 264. Which Samba parameter restricts access to a share to specified users or groups?

1. share users
2. allowed users
3. valid users
4. authorized users

Correct Answer: 3. valid users

Explanation :-

The Samba valid users parameter specifies which users or groups are permitted to access a particular share. For example, valid users = @sales can restrict access to members of the sales group. This is different from browseable, which controls whether the share appears in browse lists, and read only, which controls whether permitted users can modify files. Samba access control can involve several layers, including Unix permissions, Samba configuration, and authentication. Administrators should therefore verify both Samba-level restrictions and underlying file-system permissions when troubleshooting access problems.

Question 265. Which DNS record type is used to associate a service with a hostname and port?

1. TXT
2. SRV
3. MX
4. NS

Correct Answer: 2. SRV

Explanation :-

An SRV record specifies the location of a service by identifying a target hostname and port, along with priority and weight values. It is commonly used by protocols and applications that need service discovery, such as SIP and certain directory services. The record has a structured format containing service, protocol, priority, weight, port, and target fields. MX records are specifically used for mail delivery, NS records identify authoritative DNS servers, and TXT records contain arbitrary text information. SRV records therefore provide a standardized way for clients to discover where particular network services are available.

Question 266. Which Linux command requests a DHCP lease from a DHCP server using the common ISC DHCP client?

1. dhcp-request
2. dhclient
3. ip dhcp
4. dhcpctl

Correct Answer: 2. dhclient

Explanation :-

The dhclient utility is the traditional ISC DHCP client used on many Linux systems to obtain network configuration from a DHCP server. It can request an address and other options such as DNS servers, gateways, and domain information. Administrators may use dhclient during network troubleshooting to renew or obtain a lease on an interface. Modern Linux distributions may use NetworkManager or systemd-networkd instead, so the exact client utility depends on the system. Nevertheless, understanding DHCP client behavior and dhclient remains relevant to Linux network administration and troubleshooting.

Question 267. Which Postfix parameter specifies networks that are trusted to relay mail through the server?

1. relay_networks
2. trusted_hosts
3. mynetworks
4. allowed_relays

Correct Answer: 3. mynetworks

Explanation :-

The Postfix mynetworks parameter defines the IP addresses or networks that Postfix considers trusted for relay access under its configured restrictions. It is commonly used to permit mail submission from local or organizational networks. Administrators must configure this carefully because overly broad trusted networks can permit unauthorized relay activity. relay_domains serves a different purpose by defining destinations for which the server provides relay service. mydestination identifies domains delivered locally. Understanding these parameters is essential when configuring Postfix to distinguish local delivery, trusted submission, and relay behavior.

Question 268. Which Dovecot authentication database setting identifies the database used to verify a user’s password?

1. maildb
2. userdb
3. authdb
4. passdb

Correct Answer: 4. passdb

Explanation :-

Dovecot’s passdb configuration defines the password database used for authentication. It can use sources such as system accounts, SQL databases, LDAP, or other supported authentication mechanisms. The userdb configuration serves a different purpose: it provides information about the user’s mailbox location, UID, GID, and related account properties. Separating authentication credentials from user mailbox information gives Dovecot flexibility when integrating with external identity systems. When troubleshooting authentication, administrators should therefore determine whether the problem is in passdb, userdb, the authentication mechanism, or the underlying credential source.

Question 269. Which SSH command option specifies a non-default TCP port for the remote SSH server?

1. -i
2. -p
3. -P
4. -t

Correct Answer: 2. -p

Explanation :-

The OpenSSH client -p option specifies the TCP port on which the remote SSH server is listening. For example, ssh -p 2222 user@server.example.com connects to TCP port 2222 instead of the default SSH port 22. The -i option specifies a private identity key, while -t requests allocation of a pseudo-terminal. Using the correct port is important when SSH has been configured to listen on a non-standard port. Administrators can combine -p with other options when troubleshooting connectivity or accessing servers with customized SSH configurations.

Question 270. Which command temporarily changes SELinux from enforcing mode to permissive mode?

1. getenforce 0
2. sestatus –permissive
3. setenforce 0
4. selinux permissive

Correct Answer: 3. setenforce 0

Explanation :-

The setenforce 0 command temporarily changes SELinux from enforcing mode to permissive mode. In permissive mode, SELinux policy violations are logged but are not enforced as access denials. This can be useful for controlled troubleshooting when determining whether SELinux is contributing to a problem. The change is generally temporary and does not permanently alter the system’s SELinux configuration. getenforce reports the current mode, while sestatus provides broader status information. Administrators should use permissive mode carefully and return to enforcing mode after troubleshooting when appropriate.

Question 271. Which nftables command creates a new table named filter in the inet address family?

1. nft add table inet filter
2. nft create filter inet
3. nft table add inet filter
4. nft new inet filter table

Correct Answer: 1. nft add table inet filter

Explanation :-

The nftables command nft add table inet filter creates a table named filter in the inet address family. The inet family allows rules to handle both IPv4 and IPv6 traffic. Tables provide organizational containers for chains, sets, maps, and related firewall objects. After creating a table, administrators can create chains within it and then add rules. The command structure follows nftables’ object hierarchy, where add table identifies the operation and the family and table name specify the target. Correct table creation is the first step in building many nftables configurations.

Question 272. Which DNS command can display the canonical name associated with an alias?

1. dnsalias
2. named -C
3. host
4. zoneinfo

Correct Answer: 3. host

Explanation :-

The host utility performs DNS lookups and can display information about aliases and their canonical names. When querying a CNAME, the output can show both the alias and the canonical hostname to which it points. host is useful for quick DNS checks and supports common record types without the more extensive output provided by dig. named is the BIND server process rather than a general-purpose lookup command. Administrators often use host, dig, and nslookup during DNS troubleshooting, selecting the tool according to the level of diagnostic detail required.

Question 273. Which Apache directive can restrict access to resources based on client authorization rules in modern Apache 2.4?

1. AllowFrom
2. Require
3. AccessControl
4. Permit

Correct Answer: 4. Require

Explanation :-

Apache 2.4 uses the Require directive as a central mechanism for authorization. It can permit or deny access based on conditions such as users, groups, host addresses, or other authorization providers. For example, Require all granted allows access to a resource, while Require valid-user requires successful authentication. Older Apache versions used directives such as Allow and Deny more directly. When managing Apache 2.4 configurations, administrators should understand the newer authorization framework and ensure that access rules are placed in the correct directory, virtual-host, or location context.

Question 274. Which NFS utility displays statistics about NFS client and server operations?

1. nfsstat
2. nfsshow
3. nfsinfo
4. rpcstats

Correct Answer: 1. nfsstat

Explanation :-

The nfsstat utility displays statistics related to NFS client and server operations. It can provide information about RPC calls, NFS requests, retransmissions, and other activity depending on the options and system implementation. This makes it useful for diagnosing performance and connectivity issues. For example, unusually high retransmission counts can provide clues about network or server problems. showmount serves a different purpose by displaying NFS exports, while exportfs manages exports on an NFS server. Administrators can combine nfsstat output with system and network monitoring tools for deeper troubleshooting.

Question 275. Which Postfix command can immediately request processing of messages currently waiting in the mail queue?

1. postqueue -f
2. postfix -flush
3. postsuper -r
4. postmail -f

Correct Answer: 1. postqueue -f

Explanation :-

The postqueue -f command requests that Postfix attempt to deliver messages currently waiting in its mail queue. It is commonly used when a temporary delivery problem has been resolved and the administrator wants Postfix to retry queued messages immediately rather than waiting for the normal queue-processing schedule. postqueue -p displays the queue, while postsuper is primarily used for administrative operations on queued messages. Flushing the queue does not guarantee successful delivery; messages can remain queued if the destination server, DNS, network, or other delivery conditions are still unavailable.

Question 276. Which Linux file contains static hostname-to-IP address mappings commonly consulted before DNS when configured in NSS?

1. /etc/resolv.conf
2. /etc/hosts
3. /etc/hostname
4. /etc/networks

Correct Answer: 2. /etc/hosts

Explanation :-

The /etc/hosts file contains local static mappings between IP addresses and hostnames. When the NSS configuration specifies files before dns for hostname resolution, entries in /etc/hosts are consulted before DNS. This can be useful for local systems, testing, temporary name resolution, or environments where DNS is not available. /etc/resolv.conf specifies resolver configuration such as DNS servers, while /etc/hostname normally identifies the local system hostname. The /etc/networks file has a different purpose and is not the primary source for ordinary hostname resolution.

Question 277. Which SSH server directive controls whether root is allowed to authenticate directly using SSH?

1. RootAccess
2. PermitRootLogin
3. AllowRootSSH
4. RootAuthentication

Correct Answer: 2. PermitRootLogin

Explanation :-

The OpenSSH PermitRootLogin directive controls whether the root account may authenticate directly through SSH and under what conditions. Depending on the configured value, direct root login can be disabled or restricted to specific authentication methods. This setting is found in the SSH server configuration, commonly /etc/ssh/sshd_config. It is distinct from PasswordAuthentication, which controls password-based authentication generally. Administrators should evaluate SSH access controls together because disabling one authentication method does not automatically disable other permitted methods. Configuration changes should be tested carefully before reloading the SSH daemon.

Question 278. Which command can display the current IP addresses assigned to Linux network interfaces?

1. ip addr
2. ip route
3. ip hosts
4. ip config

Correct Answer: 1. ip addr

Explanation :-

The ip addr command displays network interfaces and their assigned IP addresses. It can show IPv4 and IPv6 addresses, interface states, prefix lengths, and related information. Administrators commonly use it when troubleshooting network configuration, checking whether an address was obtained through DHCP, or verifying that an interface is active. ip route instead displays routing information. The ip utility provides modern Linux networking functionality and replaces many older commands such as ifconfig. When diagnosing connectivity, administrators often inspect both ip addr and ip route to verify addressing and routing.

Question 279. Which DNS record is commonly used to publish SPF-related information for a domain?

1. SPF
2. MAIL
3. TXT
4. AUTH

Correct Answer: 3. TXT

Explanation :-

SPF policies are commonly published in DNS TXT records. A TXT record can contain text data associated with a domain, including an SPF policy that identifies authorized mail-sending systems. Although an SPF-specific DNS record type was defined historically, modern SPF publication relies on TXT records. MX records identify mail exchangers and do not themselves define the complete SPF policy. Administrators can inspect published SPF information using commands such as dig TXT example.com. Correct DNS publication is important because mail systems may use SPF information when evaluating whether a sending host is authorized to send mail for a domain.

Question 280. Which Linux command displays active listening TCP and UDP sockets along with associated processes when run with appropriate privileges?

1. route -p
2. ss -lntup
3. ip socket
4. netroute -s

Correct Answer: 2. ss -lntup

Explanation :-

The ss -lntup command displays listening sockets using several useful options: -l shows listening sockets, -n prevents name resolution, -t selects TCP sockets, -u selects UDP sockets, and -p displays associated processes when sufficient privileges are available. This makes the command useful for identifying which services are listening on network ports. Administrators can use the output to verify whether a service is running, determine which address it is bound to, and investigate unexpected open ports. ss is the modern Linux socket-inspection utility.