Ubuntu 26.04 Tutorial / Create a VM with Network, Disk, and Console Access
Create an Ubuntu VM with a new virtual disk, a verified ISO, NAT networking, and an accessible console. This lesson uses a manually operated installer in VirtualBox 7.2 and ends before writing an operating system to disk.
Check the host and image first
Use an image matching the host architecture and verify that the virtualization product supports that host. Do not assume an amd64 ISO runs through ordinary hardware virtualization on an ARM host. Record the actual 26.04 LTS image filename and its verification result.
An example Server VM allocation is 2 virtual CPUs, 4 GB RAM, and a 30 GB disk. This is a planning example rather than an official minimum. Check the intended workload and spare host resources; snapshots and ISOs also consume host storage.
Create the VM and an independent disk
- Choose New in VirtualBox, then select a name, storage folder, and verified ISO. If 26.04 has no separate entry, use a supported Ubuntu 64-bit guest type after checking compatibility.
- Skip unattended installation so you can follow the Ubuntu installer manually. This avoids confusing automatically created accounts with accounts created during the lesson.
- Allocate CPU and memory, then create a new virtual hard disk. Do not reuse an existing VDI/VMDK or pass through a physical host disk.
- Before booting, inspect Settings → Storage and distinguish the virtual hard disk from the ISO in the optical drive.
The VirtualBox VM creation guide explains the creation options and supported configurations.
Prepare networking and console access
Enable the first adapter under Settings → Network and start with NAT without port forwarding. NAT supports guest-initiated downloads but does not guarantee direct SSH access from the host to the guest address. Bridging can expose the guest to the physical LAN and requires checking that network’s policy.
Enable shared folders, bidirectional clipboard, and drag and drop only when an exercise needs them. The VM window is your installation and recovery console even when guest networking fails. Check the displayed host key for releasing captured keyboard and mouse input.
Boot the installer and identify devices
Start the VM and confirm that the Ubuntu boot menu and first installer screen appear. Choose the firmware boot mode before installation and avoid switching between UEFI and legacy mode afterwards. Reaching the installer does not mean installation or disk writing has completed.
Match the installer’s destination-disk size to the new virtual disk. The optical device containing the ISO is different from the disk receiving Ubuntu. If several disks appear or the capacity is unexpected, stop and inspect VM storage settings before installation.
Troubleshoot boot failures by cause
| Symptom | Check first |
|---|---|
| No bootable medium | ISO attachment, complete download, and boot order |
| VM does not start | Host virtualization support, exact error, and coexistence requirements |
| Blank or stalled installer | Image architecture, graphics configuration, and official known issues |
| Unexpected disks | Existing disk attachments and the VM configuration location |
Do not broadly disable host security or Secure Boot as a generic fix. Record the error, host and tool versions, ISO name, and VM settings; change one relevant setting at a time. Keep the working boot configuration with your lab plan.
Prepare a host-only adapter for remote exercises
The first installation boot can use NAT alone. Before SSH or firewall exercises, add the dedicated network below. Host-only networking connects the host and its VMs; it does not publish the VM onto the physical LAN or internet.
- Shut down the VM cleanly. In VirtualBox Manager, open File → Tools → Network Manager, or the Network tool, and create a dedicated host-only network. Labels differ across hosts.
- Set its host IPv4 address to 192.168.56.1 and mask to 255.255.255.0 after checking for overlap. Disable DHCP on this new dedicated network for static-address exercises; preserve DHCP used by other VMs.
- Keep adapter 1 as NAT in VM Settings → Network. Enable adapter 2, select the host-supported Host-only Adapter or Host-only Network, attach the dedicated network, and enable its cable connection.
- On a Linux client VM on the same host, use NAT on adapter 1 and the same host-only network on adapter 2. Use a fresh installation or resolve the clone identity issues first.
| Role | Host-only address | Internet path |
|---|---|---|
| Host | 192.168.56.1/24 | Retain the host’s existing connection |
| Ubuntu Server VM | 192.168.56.20/24 | DHCP route on NAT adapter 1 |
| Permitted Linux client | 192.168.56.10/24 | DHCP route on NAT adapter 1 |
After boot, record actual NIC names, MACs, and addresses with ip -br link and ip -br address and compare MACs with VirtualBox. enp0s3/enp0s8 are examples, not guaranteed names. This step prepares virtual connectivity; it does not yet configure guest static addresses.
