Proxmox Installation Considerations

• Ensure that Proxmox VE is installed successfully and that the Web GUI is accessible. Proxmox is free to use, and no license purchase is required unless enterprise support services are needed.

• If deploying the Proxmox server using a USB disk, the Proxmox ISO image must be written in DD image mode using a FAT32 file system. Failure to do so may prevent the installer from reading the ISO correctly.
• During installation, if the Proxmox installer repeatedly displays: testing device dev/sr0 for ISO.

  Unplug and re‑plug the USB disk. This allows the installer to retry ISO detection on devices such as /dev/sdx. For more details, see https://forum.proxmox.com/threads/error-no-device-with-valid-iso-found.134510/.

• If a warning such as failed to prepare efi boot appears after the installation is completed, means the installation is failed.

  In this case, destroy the existing RAID disk, recreate the virtual disk, rebuild the RAID configuration, and ensure boot is enabled for that disk. If the Proxmox installer still cannot detect the virtual disk, destroy the RAID and proceed with non‑RAID mode installation.

  For more details, see https://forum.proxmox.com/threads/proxmox-7-0-failed-to-prepare-efi.95466/.

• For networking, do not configure Proxmox networking via the shell or run: systemctl restart networking as this may cause VM network connectivity to drop. Always configure networking through the Proxmox GUI. If network issues occur, reboot the server to restore connectivity.

• It is also unnecessary to create VLAN interfaces on the host (for example, em1.200). Instead, configure the VLAN tag directly on the VM’s network device within the Proxmox UI.