Every installer screen explained, in the order you meet them
Installing Ubuntu Server on ESXi is two jobs: building a virtual machine, and then answering about ten screens of installer questions. Neither is hard, but a few of those screens hide decisions that follow the server for its whole life - the storage layout, the network address, one small SSH checkbox. This walkthrough takes them in the order you will meet them, explains what each choice really means, and stops honestly at the first login - everything after that is configuration, which has its own guide.
Two things: an ESXi host you can log in to, and the Ubuntu Server ISO downloaded from ubuntu.com. Pick a current LTS release - the long term support versions are the ones that get five years of updates, and they are what almost every guide and tutorial assumes. Upload the ISO to a datastore on the host first (Datastore browser, then Upload), because the virtual machine will boot from it.
Honest sizing note: Ubuntu's documented minimums are small - around 1.5 GB of RAM gets the installer running - but a server you actually plan to use deserves at least 2 to 4 GB of RAM and 25 GB or more of disk. You can grow the disk later; shrinking it is the painful direction.
In the ESXi web client choose Create / Register VM, then Create a new virtual machine. The choices that matter:
Leave the firmware on its default, which is EFI on current defaults. Ubuntu fully supports EFI and Secure Boot, so there is no reason to switch anything here.
Power on the VM and open its console. The boot menu offers Try or Install Ubuntu Server - select it and press Enter (it also continues on its own after a short wait). The installer first runs a quick hardware detection, then the welcome screen asks for your language. Choose it and press Continue.
Next is the keyboard layout screen. Take the ten seconds to pick the right layout and test a few keys in the box provided - a wrong layout turns your password into a puzzle later, and the installer cannot see you typing it.
Current releases offer two flavours on the type of installation screen:
For a first server or a learning machine, choose the regular Ubuntu Server. Minimized is genuinely smaller, but it also leaves out everyday tools beginners expect to find, and adding them back one by one costs more time than it saves.
The network connections screen shows your virtual network card. By default it asks DHCP for an address, and for most home and lab installs that is all you need - note the address it receives, because that is where you will reach the server.
If this server must always live at the same address - and real servers usually must - select the adapter, choose Edit IPv4, switch to Manual and type the subnet in CIDR form (for example 192.168.1.0/24), the address, the gateway and the name servers. This choice deserves its own careful look, and the separate guide on this page covers the network screen field by field.
The proxy screen can be left empty unless your network forces traffic through a proxy. The mirror screen picks the Ubuntu archive nearest to you and tests it; accept the default it offers.
The guided storage configuration screen offers Use an entire disk. Since this is a brand new virtual disk, that is the right choice - there is nothing on it to protect. The option Set up this disk as an LVM group is ticked by default, and leaving it ticked is the sensible default for most people; it makes growing the disk later much easier.
Press Done and the installer shows the storage configuration review screen: the partitions it is about to create, including the small EFI partition and the main LVM volume. Read it, then confirm. A final warning asks one more time because the next step writes to the disk - on a fresh virtual disk that is exactly what you want.
The profile setup screen asks for your name, the server name (the hostname other machines will see), a username and a password. This first user is the administrator - it can use sudo for system tasks. Pick a password you will still remember next month; you will type it at the first login.
Then comes the SSH setup screen, and the single most useful tick of the whole install: Install OpenSSH server. It is not ticked by default. Tick it. A server has no desktop and no browser - after installation you will manage it almost entirely over SSH from your own computer, and installing the SSH server now saves you a console trip later. The screen also offers to import an SSH key from GitHub or Launchpad; a beginner can skip that and use password login.
The last choice screen lists featured server snaps - popular server applications offered as one-tick extras. Leave them all unticked. A clean base system is the right starting point; anything you need can be installed later, on purpose, when you know why you need it.
Now the installer copies the system, which takes a few minutes depending on your storage speed. When it shows Reboot Now, press it. The VM restarts and may ask you to remove the installation medium and press Enter - in a VM that simply means ESXi detaches the ISO. If the installer appears again instead of a login prompt, the VM has booted the ISO a second time; shut the VM down, disconnect the CD/DVD drive in its settings, and power it on again.
You are done when the console shows a text login prompt with your server name. Type the username and password from the profile screen - the password stays invisible while you type, which is normal - and you are at your first command line.
The complete installation on a live ESXi host - creating the virtual machine and working through the installer screens exactly as they appear.
Watch Full VideoA current LTS (long term support) release. LTS versions receive five years of standard updates and are what documentation and tutorials assume. The installer screens change very little between recent LTS releases, so this walkthrough applies to both of the versions most people install today.
Ubuntu's documented minimums are roughly 1.5 GB of RAM and a few GB of disk for a minimal system, but that is a floor, not a recommendation. For a server you will actually use, start with 2 vCPUs, 4 GB of RAM and at least 25 GB of disk. Virtual hardware can be adjusted later, and growing a disk is far easier than shrinking one.
No. Log in at the console, then run sudo apt update followed by sudo apt install openssh-server. The SSH server installs in a minute and starts automatically. Ticking the box during installation is simply the same job done earlier and with less typing.