Getting Started With Azure Virtual Machines

A coworker asked me last week why her new Azure VM was costing more than expected, and the honest answer is that almost nobody gets the sizing and disk choices right the first time. Azure Virtual Machines are one of the most basic building blocks in Azure, but the create blade has enough options to make a simple task feel complicated.

Picking a size

Start smaller than you think you need. A B-series burstable VM (like a B2s or B2ms) is cheap and fine for testing, light web servers, or a dev box that isn't running heavy workloads all day. The D-series is the general purpose workhorse for production apps. Don't jump straight to a big size because you're worried about performance, you can resize a VM later with a quick restart, so there's no reason to overpay from day one.

Disks matter more than people expect

The OS disk type you pick changes both cost and performance. Standard HDD is the cheapest but slow, fine for something that barely gets used. Standard SSD is a reasonable middle ground for most general purpose VMs. Premium SSD costs more but gives you consistent, predictable performance, worth it for anything running a database or handling real traffic. Whatever you pick, turn on Azure Backup from the start. Setting it up after something goes wrong is a bad day.

Networking basics

Every VM needs a network interface and, usually, a network security group controlling what traffic can reach it. Don't open RDP or SSH to the whole internet (0.0.0.0/0), that's one of the most common ways VMs get compromised within hours of being created. Use Azure Bastion or restrict the NSG rule to your own IP address instead.

A few habits that save money later

Turn on auto shutdown for dev and test VMs, even a schedule as simple as "off at 7pm" adds up over a month. Tag every VM with an owner and a purpose when you create it, six months from now nobody will remember what "test-vm-03" was for. And check the Azure Advisor recommendations occasionally, it will flag VMs that are oversized for what they're actually using.

None of this is complicated once you've done it a few times. The mistakes are almost always the same ones: picking a size too big, forgetting backup, and leaving management ports open to the internet. Get those three right and the rest is just details.