Explanation
The IP address/default gateway combination that the administrator should have used for the new server is IP address: 192.168.10.2/24 and Default gateway: 192.168.10.1. The IP address and the default gateway of a device must be in the same subnet to communicate with each other. A subnet is a logical division of a network that allows devices to share a common prefix of their IP addresses. The subnet mask determines how many bits of the IP address are used for the network prefix and how many bits are used for the host identifier. A /24 subnet mask means that the first 24 bits of the IP address are used for the network prefix and the last 8 bits are used for the host identifier. Therefore, any IP address that has the same first 24 bits as the default gateway belongs to the same subnet. In this case, the default gateway has an IP address of 192.168.10.1/24, which means that any IP address that starts with 192.168.10.x/24 belongs to the same subnet. The new server has an IP address of 192.168.1.1/24, which does not match the first 24 bits of the default gateway, so it belongs to a different subnet and cannot communicate with the default gateway. To fix this issue, the administrator should change the IP address of the new server to an unused IP address that starts with 192.168.10.x/24, such as
192.168.10.2/24.

An incremental backup only backs up files that have changed since the last backup, whether it was a full or an incremental backup. Therefore, an incremental backup file may require another file to restore data, depending on the sequence of backups. A full backup backs up all files and does not require any other file to restore data.
A snapshot is a point-in-time copy of data that does not depend on other files. A differential backup backs up files that have changed since the last full backup and does not require any other file to restore data.

These are the port numbers that must be configured on a host-based firewall for a server that needs to allow SSH, FTP, and LDAP traffic. A port number is a numerical identifier that specifies a communication endpoint for a network protocol or an application. A host-based firewall is a software tool that monitors and controls incoming and outgoing network traffic on a single host based on predefined rules. SSH (Secure Shell) is a protocol that allows secure remote access and file transfer over an encrypted connection. The default port number for SSH is 22. FTP (File Transfer Protocol) is a protocol that allows transferring files between hosts over a network connection. The default port number for FTP is 21. LDAP (Lightweight Directory Access Protocol) is a protocol that allows accessing and managing directory services over a network connection. The default port number for LDAP is 389. Reference: https://www.howtogeek.com/190014/virtualization-basics-understanding-techniques-and-fundamentals/ https://www.howtogeek.com/220152/what-is-the-difference-between-127.0.0.1-and-0.0.0.0/ https://www.howtogeek.com/428483/what-is-end-to-end-encryption-and-why-does-it-matter/

The bootloader configuration file is used to specify which kernel version and options to use when booting the system. The first kernel stanza in the file is the default one that is loaded automatically. By editing this stanza and changing it to point to the last known-good kernel files, the administrator can boot the system with a working kernel and avoid any compatibility issues with the new kernel update. Verified Reference: [How To Change The Linux Kernel Version]