loc_az_hci/docs/temporary/UBUNTU_INSTALL_DISK_SELECTION.md

Ubuntu Installation: Disk Selection Guide

Problem

Ubuntu installer is trying to use more disk space than the VM's allocated disk, or showing multiple storage devices.

Solution: Select Only the Correct Disk

During Ubuntu installation, you need to manually select only the VM's hard disk and ignore the CD-ROM/ISO.

Step-by-Step: Disk Selection

1. During Ubuntu Installation:

   • When you reach "Storage configuration" or "Installation type"
   • Select "Custom storage layout" or "Manual"

2. Identify the Correct Disk:

   • Look for disk with size matching your VM:
     • VM 100 (cloudflare-tunnel): ~40GB disk
     • VM 101 (k3s-master): ~80GB disk
     • VM 102 (git-server): ~100GB disk
     • VM 103 (observability): ~200GB disk
   • Ignore the CD-ROM/ISO (usually shows as ~3GB or "CD/DVD")

3. Select Only the Hard Disk:

   • Click on the hard disk (not the CD-ROM)
   • The disk should show as:
     • Device: /dev/sda or /dev/vda (SCSI/VirtIO)
     • Size: Matches your VM's disk size
     • Type: "SCSI disk" or "VirtIO Block Device"

4. Partition the Disk:

   • Select the hard disk
   • Click "Add partition" or "Use entire disk"
   • Recommended: "Use entire disk" for simplicity
   • Or create partitions:
     • EFI Boot: 512MB (if UEFI)
     • Root (/): Rest of disk
     • Swap: Optional (2-4GB)

5. Continue Installation:

   • Review the partition layout
   • Ensure only the hard disk is selected
   • Click "Done" or "Continue"

What to Ignore

• ❌ CD/DVD drive (ide2) - This is the Ubuntu ISO, NOT a disk
• ❌ Any device showing ~3GB - This is likely the ISO
• ❌ Floppy drive (if shown) - Ignore this

Expected Disk Sizes

VM	Disk Size	Device Name
VM 100	40GB	/dev/sda or /dev/vda
VM 101	80GB	/dev/sda or /dev/vda
VM 102	100GB	/dev/sda or /dev/vda
VM 103	200GB	/dev/sda or /dev/vda

Troubleshooting

Installer shows "Not enough space":

• You might have selected the CD-ROM instead of the hard disk
• Go back and select the larger disk (matches your VM size)

Multiple disks shown:

• Select only the disk matching your VM's size
• Ignore the CD-ROM (smaller, ~3GB)

Can't find the correct disk:

• Look for the largest disk (matches your VM size)
• Check device names: /dev/sda or /dev/vda for SCSI/VirtIO

Quick Reference

During Installation:

1. Storage Configuration → Custom/Manual
2. Select disk matching your VM size (40GB, 80GB, 100GB, or 200GB)
3. Ignore CD-ROM (smaller, ~3GB)
4. Use entire disk or create partitions
5. Continue installation

Visual Guide

Ubuntu Installer Storage Selection:

┌─────────────────────────────────────┐
│ Storage Devices                     │
├─────────────────────────────────────┤
│ ☐ CD/DVD Drive (ide2)               │  ← IGNORE THIS
│   3.2 GB - ubuntu-24.04.iso         │
├─────────────────────────────────────┤
│ ☑ SCSI Disk (scsi0)                 │  ← SELECT THIS
│   40 GB - local-lvm:vm-100-disk-0   │
└─────────────────────────────────────┘

Summary

• ✅ Select only the hard disk (matches your VM size)
• ❌ Ignore the CD-ROM (ISO image, ~3GB)
• ✅ Use entire disk for simplicity
• ✅ Continue with installation