CompTIA Updated XK0-005 Exam Questions and Answers by zakaria

The command dig @10.10.10.20 example.com mx will query the DNS server to get mail server information. The dig command is a tool for querying DNS servers and displaying the results. The @ option specifies the DNS server to query, in this case 10.10.10.20. The mx option specifies the type of record to query, in this case mail exchange (MX) records, which identify the mail servers for a domain. The domain name to query is example.com. This command will show the MX records for example.com from the DNS server 10.10.10.20. This is the correct command to use to accomplish the task. The other options are incorrect because they either use the wrong syntax (@example.com 10.10.10.20 instead of @10.10.10.20 example.com), the wrong type of record (a or ptr instead of mx), or the wrong domain name (example.com ns instead of example.com mx). References: CompTIA Linux+ (XK0-005) Certification Study Guide, Chapter 13: Managing Network Services, page 415.

This command will load the KVM module as well as any related dependencies, such as kvm-intel or kvm-amd, depending on the processor type. The modprobe command is a Linux utility that reads the /etc/modules.conf file and adds or removes modules from the kernel. It also resolves any dependencies between modules, so that they are loaded in the correct order.

The other options are incorrect because:

B. insmod kvm

This command will only load the KVM module, but not any related dependencies. The insmod command is a low-level Linux utility that inserts a single module into the kernel. It does not resolve any dependencies between modules, so they have to be loaded manually.

C. depmod kvm

This command will not load the KVM module at all, but only create a list of module dependencies for modprobe to use. The depmod command is a Linux utility that scans the installed modules and generates a file called modules.dep that contains dependency information for each module.

D. hotplug kvm

This command is invalid and does not exist. The hotplug mechanism is a feature of the Linux kernel that allows devices to be added or removed while the system is running. It does not have anything to do with loading modules.

This command will use the tr tool to translate all lowercase letters in the testfile to uppercase letters and write the output to the uppercase file. The first argument ‘[a-z]’ specifies the set of characters to be replaced, and the second argument ‘[A-Z]’ specifies the set of characters to replace with. The ‘<’ symbol redirects the input from the testfile, and the ‘>’ symbol redirects the output to the uppercase file12.

References: 1: Linux Tr Command - javatpoint 2: Linux tr Command with Examples - phoenixNAP

These commands will unmask the mariadb service, which is currently prevented from starting, and then start it normally. The other commands are either not relevant, not valid, or not sufficient for this task. For more information on how to manage masked services with systemctl, you can refer to the web search result 1.