CompTIA Updated XK0-005 Exam Questions and Answers by roscoe

The commands nslookup or host can be used to determine whether a hostname is in the DNS. The DNS is the domain name system, which is a service that translates domain names into IP addresses and vice versa. The nslookup command is a tool for querying the DNS and obtaining information about a domain name or an IP address. The host command is a similar tool that performs DNS lookups. Both commands can be used to check if a hostname is in the DNS by providing the hostname as an argument and seeing if the command returns a valid IP address or an error message. For example, the command nslookup www.google.com or host www.google.com will return the IP address of the Google website, while the command nslookup www.nosuchdomain.com or host www.nosuchdomain.com will return an error message indicating that the hostname does not exist. These commands will supply the information that is needed to determine whether a hostname is in the DNS. These are the correct commands to use for this task. The other options are incorrect because they do not query the DNS or obtain information about a hostname (rsync or netstat). References: CompTIA Linux+ (XK0-005) Certification Study Guide, Chapter 12: Managing Network Connections, page 378.

The vi text editor is a popular and powerful tool for editing text files on Linux systems. The vi editor has two modes: command mode and insert mode. In command mode, the user can issue commands to manipulate the text, such as moving the cursor, deleting, copying, pasting, searching, replacing, and saving. In insert mode, the user can type text into the file. To switch from command mode to insert mode, the user can press various keys, such as i, a, o, I, A, or O. To switch from insert mode to command mode, the user can press the Esc key.

To insert a character at the end of the current line in the vi editor, the user can press the A key in command mode. This will move the cursor to the end of the line and switch to insert mode. Then, the user can type the desired character and press Esc to return to command mode. The statement D is correct.

The statements A, B, C, and E are incorrect because they do not perform the desired task. The p key in command mode will paste the previously copied or deleted text after the cursor. The r key in command mode will replace the character under the cursor with another character. The bb key in command mode will move the cursor back two words. The i key in command mode will switch to insert mode before the cursor. References: [How to Use vi Text Editor in Linux]

The command hostnamectl set-hostname Comptia-WebNode -H root@192.168.2.14 sets the hostname of the web server to Comptia-WebNode and connects to the server using the SSH protocol and the root user. This is the correct way to complete the requirement. The other options are incorrect because they either display the current hostname status (hostnamectl status), set an invalid hostname (hostnamectl set-hostname "$(perl -le "print" "A" x 86)"), or set a transient hostname that is not persistent (hostnamectl set-hostname Comptia-WebNode --transient). References: CompTIA Linux+ (XK0-005) Certification Study Guide, Chapter 9: Managing System Components, page 291.

The error "No space left on device" usually means either disk space or inodes are exhausted.

Checking the disk space (df -h), we see only 6.1MB is used, meaning there is plenty of free space (1.9GB available).

Checking inodes (df -i), we see all 2048 inodes are used (IUsed = 2048, IFree = 0), meaning no new files can be created even though space is available.

Inodes are metadata structures used to track files. Small files or a large number of directories can exhaust inodes before disk space runs out.

Remove unnecessary small files to free inodes:find /app -type f -exec rm -f {} +

Remove unnecessary small files to free inodes:find /app -type f -exec rm -f {} +

Remove unnecessary small files to free inodes:find /app -type f -exec rm -f {} +

Recreate the filesystem with a higher inode count:bashCopyEditmkfs.ext4 -N 500000 /dev/vdb

Recreate the filesystem with a higher inode count:bashCopyEditmkfs.ext4 -N 500000 /dev/vdb

Recreate the filesystem with a higher inode count:bashCopyEditmkfs.ext4 -N 500000 /dev/vdb

Recreate the filesystem with a higher inode count:bashCopyEditmkfs.ext4 -N 500000 /dev/vdb

Fixing the Issue:References:

Filesystem Inodes – Linux Documentation