CompTIA Updated XK0-005 Exam Questions and Answers by cairo

To change the swappiness parameter to 0 and make it persistent across reboots and applied immediately, the administrator can perform the following steps:

Append the line vm.swappiness=0 to the file /etc/sysctl.conf using echo "vm.swappiness=0" >> /etc/sysctl.conf (A). This will set the swappiness parameter to 0 for future boots.

Reload the sysctl configuration using sysctl -p (A). This will apply the changes to the current system without rebooting. The other commands will not achieve this task, but either write to a wrong file, use a wrong option, or have a syntax error. References:

[CompTIA Linux+ Study Guide], Chapter 8: Optimizing Linux Performance, Section: Tuning Kernel Parameters with sysctl

[How to Change Swappiness in Linux]

For repairing XFS filesystems, the appropriate command is xfs_repair. Since the /opt/finapp directory resides on an XFS filesystem (indicated in the mount output), xfs_repair is suitable for diagnosing and fixing corruption in XFS inodes and extent trees. Using fdisk or fsck.ext4 is not appropriate for XFS filesystems, as these commands are intended for partitioning and ext4 filesystems, respectively. Reference: CompTIA Linux+ Study Guide.

The cause of the issue based on the output above is C. The inodes is at full capacity and would affect file creation for users.

An inode is a data structure that stores information about a file or directory, such as its name, size, permissions, owner, timestamps, and location on the disk. Each file or directory has a unique inode number that identifies it. The number of inodes on a filesystem is fixed when the filesystem is created, and it determines how many files and directories can be created on that filesystem. If the inodes are exhausted, no new files or directories can be created, even if there is enough disk space available.

The output for the second command shows that the /ftpusers/ filesystem has 0% of inodes available, which means that all the inodes have been used up. This would prevent users from creating new files on the FTP server. The administrator should either delete some unused files or directories to free up some inodes, or resize the filesystem to increase the number of inodes.

The other options are incorrect because:

A. The users do not have the correct permissions to create files on the FTP server.

This is not true, because the output for the first command shows that the /ftpusers/ filesystem has 26% of disk space available, which means that there is enough space for users to create files. The permissions of the files and directories are not shown in the output, but they are not relevant to the issue of inode exhaustion.

B. The ftpusers filesystem does not have enough space.

This is not true, because the output for the first command shows that the /ftpusers/ filesystem has 26% of disk space available, which means that there is enough space for users to create files. The issue is not related to disk space, but to inode capacity.

D. ftpusers is mounted as read only.

This is not true, because the output for the first command does not show any indication that the /ftpusers/ filesystem is mounted as read only. If it was, it would have an (ro) flag next to the mounted on column. A read only filesystem would prevent users from creating or modifying files on the FTP server, but it would not affect the inode usage.

The file command is used to determine the type of a file by examining its contents. It can recognize many different formats, such as text, binary, executable, compressed, image, audio, video, etc. It can also display some additional information about the file, such as encoding, size, dimensions, etc12

References: 1: file(1) - Linux manual page 2: How to use the file command in Linux