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Today's topic is one that almost everyone has heard of, but most people don't fully understand,

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as your disk storage, it's the virtual hard drive for your cloud VMs and here's the thing,

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every single VM you create needs storage. Pick the wrong type and you're either paying way too much,

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or getting terrible performance. By the end of this episode, you'll know the four main disc types

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and exactly when to use each one. Grab your coffee and let's dive in.

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Why disk type matters? Speed, capacity and cost. So why does disk type even matter?

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Three factors determine performance. I/OPS, throughput and latency. I/OPS stands for input,

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output operations per second. Basically how many read or write operations the disk can handle at once.

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throughput is the data transfer speed measured in megabytes per second.

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Latency is the delay. How long that first byte takes to arrive after you ask for it?

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Think of it like vehicles. As the Dan handles daily errands just fine,

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a pickup truck holds heavier loads and a race car is built for pure speed.

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Different disk types follow the same pattern. Standard SSD is your sedan.

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Premium SSD is the work truck. Premium SSD V2 is a sports car you can tune yourself.

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And ultra-disc is a Formula 1 race car. Here's the trade-off, higher performance costs more money.

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The trick is matching the disk to what your workload actually needs,

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so you're not over-provisioning and wasting cash,

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nor under-provisioning and getting slow performance.

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So let's start with the two broad categories of disks you'll attach to a VM.

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OSDisk versus DataDisk, the two flavors. When you create a VM in Azure,

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it automatically creates an OSDisk. That disk holds the operating system, Windows or Linux,

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and it's where the VM boots from. The OSDisk maxes out at four terabytes,

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which is more than enough for the OS itself and maybe a few basic applications.

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But here's the thing, you can also add DataDisk. These are optional,

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and you attach them separately for things like applications, databases, or file storage.

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Each DataDisk can go up to 64 terabytes,

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and you can attach multiple disks to a single VM.

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Need more storage? Just add another disk.

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Now both OSDisk and DataDisk use the same four performance tiers.

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Standard SSD, premium SSD, premium SSD V2 and ultra-disk.

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The difference isn't about speed, it's about purpose.

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An OSDisk runs the operating system, a DataDisk runs your applications,

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but they both rely on the same underlying disk types.

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One more thing, as your disk storage is persistent,

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that means your data stays put even when the VM is stopped or restarted,

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nothing gets lost when you shut down for the night.

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Let's dive into the four tiers, starting with the most affordable.

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Standard SSD, the budget workhorse.

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Let's start with the entry-level option, Standard SSD.

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This is the lowest cost per gigabyte among the SSD tiers,

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and it gives you decent performance for basic workloads.

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We're talking about a maximum of around 6000 IOPS,

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and throughput up to 600 megabytes per second,

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depending on the disk size you choose.

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So when would you use it?

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Think development and test environments where you're spinning up VMs to experiment.

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Web servers that don't get heavy traffic,

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low traffic applications where a few seconds of delay isn't a big deal.

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Remember the vehicle analogy from earlier?

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Standard SSD is your reliable sedan.

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It gets you to the grocery store and back.

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It handles the daily commute just fine,

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but you wouldn't use it to hold a trailer full of lumber or race on a track.

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It's built for everyday tasks, not heavy lifting.

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And here's where you need to be honest with yourself.

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If you're running any kind of production database,

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SQL server, Oracle, MySQL, skip standard SSD.

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Same goes for anything sensitive to latency,

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like real-time applications,

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or anything that needs a ton of IO operations per second.

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Standard SSD just isn't built for that.

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For those scenarios, you need a step-up, premium SSD.

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Premium SSD, the reliable pro.

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Premium SSD handles production workloads without breaking a sweat.

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You get consistent low latency and much higher IO apps than standard SSD.

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This is where real performance starts showing up.

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Here's the simple breakdown.

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With premium SSD, performance is directly tied to the disk size.

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Pick a disk size and that determines how many IO apps you unlock.

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A P30 at one terabyte gives you 5,000 IOPS.

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A P60 at four terabytes delivers 20,000 IOPS.

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Bigger disk means more performance.

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So when should you reach for it?

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Enterprise applications that need reliable performance.

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SQL server databases that aren't massive,

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but still demand consistent response times.

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Virtual desktops where users expect instant feedback.

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Premium SSD handles all of that.

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But here's the limitation.

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Because performance is locked to disk size,

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you're stuck in fixed tiers.

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One more IOPS, you have to buy a bigger disk.

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Even if you don't need the extra storage space,

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that leads to over-provisioning.

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Paying for capacity you never use,

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just to get the performance you actually need.

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Think of it like a dependable work truck.

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It's reliable, it's proven, and it gets the job done.

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But you're paying for the whole truck even if you only need

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the extra payload capacity once a month.

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You can't just rent the truck bed for a day and leave the cab parked.

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That exact problem is what premium SSD V2 was built to solve.

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Premium SSD V2, the flexible performer.

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Now, this is where things get interesting.

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Premium SSD V2 fixes the big issue with regular premium SSD,

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being forced to buy more capacity just to get more performance.

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With premium SSD V2, you can independently adjust capacity,

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IOPS and throughput.

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No downtime, no disk swaps, just change the settings and it happens.

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The baseline is generous, you get 3,000 IOPS

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and 125 MB/s of throughput included at no extra charge.

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That's already more than some standard SSD disks can max out at.

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From there you can scale up to 80,000 IOPS and 1,200 MB/s.

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Plenty for most general purpose enterprise workloads.

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Capacity ranges from one GB/bite up to 64 TB/bites,

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whether you need a tiny disk for a lightweight app or a massive one for a data warehouse,

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premium SSD V2 covers it and the latency sub-mily second.

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For many workloads it's comparable to ultra-disk.

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Without the ultra-price tag, here's the real value.

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Premium SSD V2 is significantly cheaper than ultra-disk for similar performance levels.

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You're not paying a premium for the name.

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You're paying for exactly what you need.

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Need high IOPS but not massive throughput?

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Tune it that way, need lots of throughput but modest IOPS?

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Tune it the other way, no one size fits all package forced on you.

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So what's it best for?

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Mainstream production databases,

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line of business applications, any workload that needs high performance but doesn't need ultra-disk

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ceiling.

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Suicosurver Oracle MongoDB Cassandra, the databases that power real businesses,

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premium SSD V2 handles them all, one limitation worth noting.

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Premium SSD V2 is currently only available with locally redundant storage or LRS.

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That means your data is replicated three times inside a single data center.

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It doesn't support zone redundant storage yet,

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so if you need your data spread across multiple availability zones for higher resilience,

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you'll need other options or add application level redundancy.

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Still for most scenarios premium SSD V2 is the sweet spot.

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You get the flexibility to right size storage,

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the performance to handle serious workloads,

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and a cost structure that doesn't punish you for wanting better IOPS.

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But if your workload demands the absolute highest performance,

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think SEPHANA electronic health records, or real-time trading.

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There's one more tier to cover.

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Ultra-disk, the supercar.

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Now let's talk about ultra-disk.

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This is the top tier. We're talking up to 400,000 IOPS per disk,

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10,000 megabytes per second of throughput,

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and latency measured in microseconds, not milliseconds.

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Microseconds, ultra-disk is built for critical workloads where you can't afford downtime.

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Apps that need to be fast, massive in-memory databases like SEPHANA,

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health record systems where doctors need info instantly,

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high frequency trading platforms where microseconds cost millions,

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AI and machine learning jobs that crunch huge data sets.

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Pricing is different too.

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Performance and capacity are separate.

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You pick your IOPS and throughput and pay for them separately from storage.

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So you can have a small disk with huge speed or a big disk with modest speed.

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You don't have to buy extra capacity just to get the IOPS.

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There's also a zone redundant storage.

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There are as copies your data across three zones in the same region.

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So if one data center goes down, your disk keeps working.

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That's important for the workloads ultra-disk handles.

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Now here's a newer feature.

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Instant access snapshots.

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It's in preview for ultra-disk and premium SSDV2.

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Normally, creating a disk from a snapshot takes time while data rehydrates.

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With instant access, you can create a disk in seconds instead of hours.

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And the new disk has near full performance right away.

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For disaster recovery, that's a big deal.

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You can spin up a full copy of your database in minutes.

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Think of ultra-disk like a Formula One racecar,

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incredible speed, every millisecond counts.

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But you don't drive a Formula One car to pick up groceries.

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It's built for one thing, going as fast as physically possible.

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And you pay for that speed.

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So when shouldn't you use it?

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For most workloads, ultra-disk is overkill.

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Premium SSDV2 covers 95% of cases for a lot less money.

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If you're not running SAP HANA or a trading platform or something extreme,

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you don't need ultra-disk.

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Start with premium SSDV2 only move to ultra if your monitoring shows you need it.

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So we've covered the four tiers.

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How do you actually choose?

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How to choose the right disk?

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So you've got the four tiers.

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Now how do you pick?

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Start with three questions.

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First, is it production or dev test?

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If it's dev test or a low traffic web server,

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standard SSD is all you need.

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Don't overthink it.

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It saves money and gives good performance.

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Second, what IOPS and latency do you need?

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If you need low latency and thousands of IOPS, you need premium.

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The question is which premium tier?

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If your workload is steady regular premium SSD works,

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if you want flexibility to adjust performance without swapping disks,

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go premium SSDV2.

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Third, what's your budget?

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This is where it gets real.

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Premium SSDV2 is cheaper than ultra for similar performance in most cases.

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But if you're running SAP HANA or a trading system,

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speed matters more than cost.

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Let me give you a quick guide.

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Dev test and web servers, standard SSD.

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Production with moderate IOPS?

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Premium SSD.

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Production with high IOPS where you want flexibility.

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Premium SSDV2.

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Extreme IOPS where sub millisecond latency is critical.

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Ultra disk.

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Here are some cost optimization tips that actually save money.

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Write size your disk from the start.

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Don't buy a 40 by premium SSD if you only need 500GB.

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Use premium SSDV2 instead of ultra when you can.

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It covers most cases for less money.

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Clean up old snapshots.

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They stack up and cost you.

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And choose LRS over ZRS if you don't need zone redundancy.

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LRS is cheaper and still gives three copies within one data center.

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One thing you don't need to worry about is encryption.

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ServerSide encryption with 256-bit AES is always on.

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It's FIPS 142 compliant.

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Nothing to enable, nothing to configure.

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Your data is encrypted addressed by default.

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If you need more control, you can use customer managed keys.

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But for most scenarios, the default encryption is enough.

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Before we wrap up, let's touch on a couple more features

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that matter for durability and security.

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Security, durability and snapshots.

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As your disk storage targets 99.9% availability thus that's 5.9s.

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How do they pull that off?

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Simple.

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Three copies of every piece of data.

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With locally redundant storage, those three copies stay inside one data center.

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A disk fails.

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Another copy takes over instantly.

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With zone redundant storage, copies spread across three availability zones in the same region.

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An entire data center goes dark.

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Your data stays safe encryption.

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Always on by default.

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ServerSide encryption uses 256-bit AES and meets FIPS 142 standards.

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That covers data addressed.

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But maybe you need more control.

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Customer managed keys let you hold the encryption keys yourself.

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Encryption at host goes further.

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It covers temp disks and disk caches,

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which the default encryption leaves out.

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For truly sensitive workloads, you can stack both.

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Snapshots are point in time backups.

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They run without slowing your disk down.

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The new instant access, snapshots for ultra-disk and premium SSD V2

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change the game entirely.

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You can create a disk from a snapshot in seconds instead of hours.

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For disaster recovery that's massive.

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Spin up a full production copy of your environment in minutes.

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So that's the core of Azure disk storage.

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Build for durability, security and speed.

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Let's bring it all together.

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Four disk types.

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Standard SSD for budget-friendly dev and test.

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Premium SSD for reliable production performance.

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Premium SSD V2 for flexible high performance without the ultra-price.

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And ultra-disk for the extreme workloads where every microsecond matters.

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Here's the bottom line.

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Match the disk type to your workload.

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Not the other way around.

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Don't buy ultra-disk because it sounds impressive.

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Don't skimp on standard SSD if you're running a production database.

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Pick the right tool for the job.

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If this episode helped you make sense of Azure disk storage,

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subscribe and share it with someone starting their Azure journey.

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And tune in next time for another knowledge nugget.