| No boot menu / USB ignored |
Legacy vs UEFI, bad stick |
Re-flash USB; force UEFI boot entry |
| Installer hangs on network |
No DHCP / dead NIC |
Plug Ethernet; or configure Wi‑Fi in Subiquity |
| Wrong disk wiped |
Selected USB as target |
Restore from backup; always confirm disk name |
Red Failed mounting cdrom… after reboot |
Installer USB already removed |
Normal — press Enter; not an install failure |
/ only ~half the disk |
Default LVM left free space in ubuntu-vg |
At Storage, edit ubuntu-lv size to fill the VG (or grow LV after install) |
ssh inactive after reboot |
OpenSSH skipped |
sudo apt-get install -y openssh-server |
| Connection timed out |
Wrong IP / firewall / Wi‑Fi AP isolation |
Re-check ip a; same LAN/VLAN as workstation |
| Permission denied |
Wrong user/password, or password auth off |
Use the Subiquity username; confirm Allow password authentication was checked |