Disk and Partitioning Concepts in a Job Context

1. Understanding Business Requirements:
• In a real-world scenario, a company might require a specific setup for hosting data. For example:
• Create a directory (/web) to host website data with a file size of 5GB.
• Use commands like mkdir /web and df -h to manage directories and check disk space.
2. Adding Hard Drives (HDD) in Different Scenarios:
• Traditional Method (Physical Connection):
• Adding a new HDD (sdb) to a server where sda already exists.
• Requires a physical reboot of the server.
• Job Perspective: You might handle physical server maintenance, HDD installation, and server reboots.
• Hot Plug Devices (USB/Pendrive):
• Connecting USB drives without needing a server reboot.
• Job Perspective: Useful in environments needing quick, temporary storage solutions or backups.
• Using SAN Box (Storage Area Network):
• SAN is used for large storage needs, where multiple hard drives are pooled.
• LUNs (Logical Unit Numbers) are created and allocated to different teams as needed.
• Job Perspective: As a system administrator or storage manager, you might configure SAN storage, create LUNs, and allocate them based on departmental requirements.
3. Connecting SAN to Linux Servers:
• LUNs: Logical partitions of SAN storage, like creating partitions on a single HDD.
• HBA Card: Used for high-speed connections to SAN, essential for enterprise environments.
• Commands for LUN Scanning:
• echo "---" > /sys/class/scsi_host/hostX/scan to scan and recognize new LUNs.
• Job Perspective: In a job, you would manage storage systems, ensure they are properly connected, and perform scans to detect new storage devices without downtime.