A Linux administrator wants to find out whether files from the wget package have been altered since they were installed. Which of the following commands will provide the correct information?
Correct Answer: D
The command that will provide the correct information about whether files from the wget package have been altered since they were installed is rpm -V wget. This command will use the rpm utility to verify an installed RPM package by comparing information about the installed files with information from the RPM database. The verification process can check various attributes of each file, such as size, mode, owner, group, checksum, capabilities, and so on. If any discrepancies are found, rpm will report them using a single letter code for each attribute. The other options are not correct commands for verifying an installed RPM package. The rpm -i wget command is invalid because -i is used to install a package from a file, not to verify an installed package. The rpm -qf wget command will query which package owns wget as a file name or path name, but it will not verify its attributes. The rpm -F wget command will freshen (upgrade) an already installed package with wget as a file name or path name, but it will not verify its attributes. Reference: rpm(8) - Linux manual page; Using RPM to Verify Installed Packages
XK0-005 Exam Question 7
Which of the following enables administrators to configure and enforce MFA on a Linux system?
Correct Answer: C
The mechanism that enables administrators to configure and enforce MFA on a Linux system is PAM. PAM stands for Pluggable Authentication Modules, which is a framework for managing authentication and authorization on Linux systems. PAM allows the administrator to define the rules and policies for accessing various system resources and services, such as login, sudo, ssh, or cron. PAM also supports different types of authentication methods, such as passwords, tokens, biometrics, or smart cards. PAM can be used to implement MFA, which stands for Multi-Factor Authentication, which is a security technique that requires the user to provide more than one piece of evidence to prove their identity. MFA can enhance the security of the system and prevent unauthorized access. PAM enables administrators to configure and enforce MFA on a Linux system. This is the correct answer to the question. The other options are incorrect because they either do not manage authentication and authorization on Linux systems (Kerberos or PKI) or do not support MFA (SELinux). Reference: CompTIA Linux+ (XK0-005) Certification Study Guide, Chapter 17: Implementing Basic Security, page 517.
XK0-005 Exam Question 8
A systems administrator is configuring a Linux system so the network traffic from the internal network 172.17.0.0/16 going out through the eth0 interface would appear as if it was sent directly from this interface. Which of the following commands will accomplish this task?
Correct Answer: A
This command will use the iptables tool to append a rule to the POSTROUTING chain of the nat table, which will match any packet with a source address of 172.17.0.0/16 and an output interface of eth0, and apply the MASQUERADE target to it. This means that the packet will have its source address changed to the address of the eth0 interface, effectively hiding the internal network behind a NAT12.
XK0-005 Exam Question 9
A Linux administrator is configuring a new internal web server fleet. The web servers are up and running but can only be reached by users directly via IP address. The administrator is attempting to fix this inconvenience by requesting appropriate records from the DNS team. The details are: Hostname: devel.comptia.org IP address: 5.5.5.1, 5.5.5.2, 5.5.5.3, 5.5.5.4 Name server: 5.5.5.254 Additional names: dev.comptia.org, development.comptia.org Which of the following types of DNS records should the Linux administrator request from the DNS team? (Select three).
Correct Answer: B,D,E
The Linux administrator should request the following types of DNS records from the DNS team: A: This record type is used to map a hostname to an IPv4 address. The administrator needs four A records for devel.comptia.org, one for each IP address (5.5.5.1, 5.5.5.2, 5.5.5.3, 5.5.5.4). This will allow users to access the web servers by using the hostname devel.comptia.org instead of the IP addresses1. CNAME: This record type is used to create an alias for another hostname. The administrator needs two CNAME records, one for dev.comptia.org and one for development.comptia.org, both pointing to devel.comptia.org. This will allow users to access the web servers by using any of these three hostnames interchangeably1. NS: This record type is used to delegate a domain or a subdomain to another name server. The administrator needs one NS record for comptia.org, pointing to 5.5.5.254, which is the name server that hosts the records for the subdomain devel.comptia.org2. This will allow users to resolve the hostnames under comptia.org by querying the name server 5.5.5.2542. The other record types are not relevant for the administrator's task: MX: This record type is used to specify the mail exchange server for a domain or a subdomain1. The administrator does not need this record type because the web servers are not intended to handle email traffic. PTR: This record type is used to map an IP address to a hostname, which is the reverse of an A record1. The administrator does not need this record type because the web servers are not expected to be accessed by their IP addresses. RRSIG: This record type is used to provide digital signatures for DNSSEC, which is a security extension for DNS that verifies the authenticity and integrity of DNS responses3. The administrator does not need this record type because it is not mentioned in the task requirements. SOA: This record type is used to provide information about the authoritative name server and other parameters for a domain or a subdomain1. The administrator does not need this record type because it is usually created automatically by the name server software when a new zone file is created4. TXT: This record type is used to store arbitrary text data that can be used for various purposes, such as SPF, DKIM, DMARC, etc1. The administrator does not need this record type because it is not related to the web server functionality. SRV: This record type is used to specify the location and port number of a service that runs on a domain or a subdomain1. The administrator does not need this record type because the web servers use the standard HTTP port 80, which does not require an SRV record.
XK0-005 Exam Question 10
A systems administrator wants to be sure the sudo rules just added to /etc/sudoers are valid. Which of the following commands can be used for this task?
Correct Answer: A
The command visudo -c can be used to check the validity of the sudo rules in the /etc/sudoers file. The visudo command is a tool for editing and validating the /etc/sudoers file, which defines the rules for the sudo command. The -c option checks the syntax and logic of the file and reports any errors or warnings. The command visudo -c will verify the sudo rules and help the administrator avoid any mistakes. This is the correct command to use for this task. The other options are incorrect because they either do not check the validity of the file (test, sudo, or cat) or do not exist (sudo vi check). Reference: CompTIA Linux+ (XK0-005) Certification Study Guide, Chapter 18: Securing Linux Systems, page 546.