Comprehensive and Detailed In-Depth Explanation:NIOS Grid Backup allows scheduled exports of the configuration database (DNS, DHCP, Grid settings) to an external server. Supported protocols ensure flexibility and security:

A (SFTP):Secure File Transfer Protocol (SSH-based) is supported for encrypted backups to remote servers (port 22). Widely used for secure transfers. Correct.

B (SCP):Secure Copy Protocol (also SSH-based) is supported, offering a simple, secure file transfer option (port 22). Correct.

C (FTP):File Transfer Protocol (unencrypted, port 21) is supported for legacy systems, though less secure. Correct.

D (HTTPS):Web-based secure transfer (port 443) is supported, allowing backups to HTTP servers with SSL/TLS encryption. Correct.

Setup:In Grid Manager (Grid > Grid Manager > Backup), you configure the protocol, server IP, and credentials.

Practical Example:In an INE lab, you’d schedule a backup using SFTP to a remote server, test restoration, and troubleshoot connectivity issues, reinforcing Grid deployment skills.

Note:All four are explicitly supported per NIOS documentation, making this a comprehensive list.References:Infoblox NIOS Administrator Guide – Grid Backup; INE Course Objective: NIOS DDI Grid Deployment.