Cost management question Azure Disk storage cost

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I am new to Azure Disk storage management Is Azure Disk the same as the Azure Blob has the cold, hot option? Also because I have so many virtual machines, every virtual machine has attached a disk like Ultra disk Premium SSD v2 Premium SSD Standard SSD Standard HDD. Imagine you have 100 vm and some attach ultra disk and premium disk, you will be poor because it cost you tremendous amount of money.

So my question is how do you save money for disk? If you are doing load performance testing the disk will receive 800 GB data every day. How do you lower the cost for storage,

does disk has the autoshutdown or autostart functionality to save money? because I heard disk cost is counting per hour. So i want to shutdown it in the evening when I sleep to save money.

How does the disk cost ? for example, if a disk is 10GB disk and 100 dollar per month. If you ingest 20 GB in that 10gb disk, will you be charged over expensively,

if you don't use that disk or just use the disk for very small amount like 0.1GB..WILL IT STILL CHARGE YOU 100 dollar per month? or it charge you 0.1*100 since you only use 0.1 amount of space.

I feel charge by hour maybe not a good choice. Does Azure have something like you use 0.1GB charge you 0.1GB dollar rather than 10GB dollar per month>? thanks

I have some new questions can some one answer? thanks Question 1:

I'm running a VM for a performance test, and my setup includes one OS disk (1024 GiB) and two data disks. During the test, approximately 10 GiB of test data is generated. I'm uncertain whether this 10 GiB of data will be stored on the OS disk or the data disks. From a cost-saving perspective, if the data goes to the OS disk, I can consider removing the two data disks. Can you provide insights into the allocation of this data? Does it typically go to the OS disk or the data disks?

Question 2:

In my current setup, I have two attached data disks to a VM. I would like to delete any underutilized data disks to optimize resource allocation and reduce costs. However, when monitoring through Azure Monitor, I can't find any information indicating the percentage of space utilized on these data disks (e.g., 2% or 3% used). Is there a method or tool to monitor the usage of data disks and identify underutilized ones effectively?

Question 3: I'm looking to optimize costs in Azure by deleting a data disk and utilizing snapshots to preserve the data for potential future use. Specifically, I have a 1024 GiB Premium disk with 10 GiB of data currently stored on it.

My question is related to the cost of creating and maintaining snapshots in this scenario. I want to understand how much I can expect to pay for these snapshots, ideally as a percentage relative to the cost of the original disk. For example, is it reasonable to assume that snapshot costs might be around 10% of the original disk cost, considering the 10 GiB of data involved?

Question 4: I'm facing a challenge in my Azure setup where I want to preserve the data stored on an Azure Ultra Disk while also reducing costs by deleting the actual Ultra Disk. To do this, I attempted to create an incremental snapshot of the Ultra Disk and then delete the original disk. I'm encountering an issue while trying to re-create a disk from an incremental snapshot of an Azure Ultra Disk. When I attempt to create the snapshot, I'm informed because it is ultra disk type that I can only create an incremental snapshot instead of a full copy. However, when I proceed with creating the incremental snapshot, it fails with a provision state error. the create disk from snapshot option is read-only. So how do you create an disk from ultra-disk incremental disk snapshot. what is difference between incremental snapshot and full copy snapshot?

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There are 3 answers

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SumanthMarigowda-MSFT On BEST ANSWER

In general, it's best practice to store data on separate data disks rather than on the OS disk. This is because storing data on the OS disk can impact the performance of the VM and can also make it more difficult to manage the data. When you create a VM in Azure, the OS disk is created by default and is used to store the operating system and any applications that you install. Any data that you generate during your performance test will be stored on the OS disk by default, unless you specifically configure your test to store the data on the data disks.

To ensure that your test data is stored on the data disks, you can configure your test to write the data to a specific location on the data disks. For example, you can create a folder on the data disks and configure your test to write the data to that folder.

If you're concerned about the cost of the data disks, you can consider using Azure Managed Disks, which allow you to pay only for the storage that you use. With Azure Managed Disks, you can also easily resize your disks as needed, which can help you optimize your costs.

Question 2:

Yes, you can see the historical data of disk space utilization in Azure Windows VM.

  1. In the Azure portal, select Virtual Machines.
  2. From the list, choose a VM and in the Monitoring section choose Metrics. You can query for historical time ranges of up to 30 days using the Time Range selector and can download to excel as shown in the image below...enter image description here

There are various disk related metric options available in the Metric dropdown.

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You can also go to Insights under Monitoring section and select the Performance Tab. VM insights monitors key operating system performance indicators related to processor, memory, network adapter, and disk utilization. It has Logical Disk Space Used % - defaults showing the average and 95th percentile.

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Following are limitations in performance collection with VM insights: • Metrics are only available for data disks on Linux virtual machines using XFS filesystem or EXT filesystem family (EXT2, EXT3, EXT4).

• Logical Disk Space Used % - shows the top five machines with the highest average disk space used % across all disk volumes.

If you are interested in a view of all monitored VMs deployed across workgroups in your subscriptions or in your environment, then you can use the Multi-VM perspective from Azure Monitor as described in detail in this document : https://learn.microsoft.com/en-us/azure/azure-monitor/vm/vminsights-performance#multi-vm-perspective-from-azure-monitor

Few other resources you might find helpful: Is there a way see used disk space with the actual disk size of the VMs in a specific subscription in azure?

Question 3:

  1. Cost of creating snapshots: Creating snapshots in Azure is generally inexpensive, as you only pay for the storage that's used by the snapshot. However, keep in mind that the cost of creating a snapshot can vary depending on the size of the disk and the frequency of the snapshots. You can use the Azure Pricing Calculator to estimate the cost of creating snapshots for your specific scenario.
  2. Cost of storing snapshots: Storing snapshots in Azure is generally less expensive than storing the original data disk, as you only pay for the changes that are made to the disk since the last snapshot. However, keep in mind that the cost of storing snapshots can vary depending on the size of the disk and the frequency of the snapshots. You can use the Azure Pricing Calculator to estimate the cost of storing snapshots for your specific scenario.
  3. Frequency of snapshots: The frequency of snapshots can impact the cost of using snapshots to preserve data. If you take frequent snapshots, you may incur higher storage costs. However, if you take infrequent snapshots, you may risk losing data if the disk fails or becomes corrupted.
  4. Recovery time: Keep in mind that recovering data from a snapshot can take time, as you need to create a new disk from the snapshot and attach it to a VM. If you need to recover data quickly, you may want to consider keeping a copy of the data disk instead of relying solely on snapshots.

Question 4:
There are a few differences between an incremental snapshot and a full snapshot. Incremental snapshots will always use standard HDD storage, irrespective of the storage type of the disk, whereas full snapshots can use premium SSDs. If you're using full snapshots on Premium Storage to scale up VM deployments, we recommend you use custom images on standard storage in the Azure Compute Gallery.

It will help you achieve a more massive scale with lower cost. Additionally, incremental snapshots potentially offer better reliability with zone-redundant storage (ZRS). If ZRS is available in the selected region, an incremental snapshot will use ZRS automatically. If ZRS isn't available in the region, then the snapshot will default to locally-redundant storage (LRS). You can override this behavior and select one manually but, we don't recommend that. Incremental snapshots are billed for the used size only. You can find the used size of your snapshots by looking at the Azure usage report. For example, if the used data size of a snapshot is 10 GiB, the daily usage report will show 10 GiB/(31 days) = 0.3226 as the consumed quantity.

Restrictions • Incremental snapshots currently can't be moved between subscriptions. • You can currently only generate SAS URIs of up to five snapshots of a particular snapshot family at any given time. • You can't create an incremental snapshot for a particular disk outside of that disk's subscription. • Incremental snapshots can't be moved to another resource group. But, they can be copied to another resource group or region. • Up to seven incremental snapshots per disk can be created every five minutes. • A total of 500 incremental snapshots can be created for a single disk. • You can't get the changes between snapshots taken before and after you changed the size of the parent disk across 4 TB boundary. For example, You took an incremental snapshot snapshot-a when the size of a disk was 2 TB. Now you increased the size of the disk to 6 TB and then took another incremental snapshot snapshot-b. You can't get the changes between snapshot-a and snapshot-b. You have to download the full copy of snapshot-b created after the resize. Subsequently, you can get the changes between snapshot-b and snapshots created after snapshot-b.

Incremental snapshots of Premium SSD v2 and Ultra Disks Incremental snapshots of Premium SSD v2 and Ultra Disks have the following extra restrictions:

Currently, incremental snapshots of Premium SSD v2 and Ultra Disks
can't be taken in the Azure portal.

• Snapshots with a 512 logical sector size are stored as VHD, and can be used to create any disk type. Snapshots with a 4096 logical sector size are stored as VHDX and can only be used to create Ultra Disks and Premium SSD v2 disks, they can't be used to create other disk types. To determine which sector size your snapshot is, see check sector size.

• Up to five disks may be simultaneously created from a snapshot of a Premium SSD v2 or an Ultra Disk.

• When an incremental snapshot of either a Premium SSD v2 or an Ultra Disk is created, a background copy process for that disk is started. While a background copy is ongoing, you can have up to three total snapshots pending. The process must complete before any more snapshots of that disk can be created.

• Incremental snapshots of a Premium SSD v2 or an Ultra disk can't be used
immediately after they're created. The background copy must complete before you can create a disk from the snapshot. See Check snapshot
status for details.

Incremental snapshots of Premium SSD v2 or Ultra Disks can't be used to create new disks until the background process copying the data into the snapshot has completed. You can use either the CLI or PowerShell sections to check the status of the background copy from a disk to a snapshot.

2
SumanthMarigowda-MSFT On

Firstly, Let me explain the difference between Disk and Storage account.

Azure Disk: Block-level storage volumes for Azure VMs. A data disk is always attached to a VM. You can't access the data on the data disk directly from internet. For the VM OS the data disk is attached to the VM and can be used by the OS and services like a "local disk" in your computer.

Azure Blobs: A massively scalable object store for text and binary data. Also includes support for big data analytics through Data Lake Storage Gen2. A Storage Account is a "serverless storage" to store data. You are able to access the data without running a VM from internet and/or VMs in Azure. A Storage account (fileshare or blob storage for example) can be used by a VM like a "network share"

Refer to this article for Hot, cool, and archive access tiers for blob data which provide detailed information Access trier, pricing, billing and more

  • Pricing calculator: Calculate your estimated hourly or monthly costs for using Azure. The Azure Pricing Calculator can help you understand the costs of moving workloads to the Azure cloud. It estimates Azure pricing once all your data and applications are in Azure.

Managed Disks pricing: https://azure.microsoft.com/en-us/pricing/details/managed-disks/

To reduce the Disks and cost optimization

The prices shown are the monthly prices. How do I get charged if I use disks for less than a month? The charges will be pro-rated on an hourly basis using the monthly price. For instance, Premium SSD for P15 is $34.56 (price may vary per region). For October, you will be billed per $34.56/(31 days x 24 hours) = $0.047/hour

How do I calculate pricing for Premium SSD v2 Disk Storage? The total cost of Premium SSD v2 Disk Storage depends on the size and number of disks you provision, and their respective configurations in terms of provisioned IOPS and throughput.

For example, if you have an application that requires three different disks with the following characteristics:

Disk 1 - 64 GiBs, 2,000 IOPS and 120 MB/s of throughput Disk 2 - 256 GiBs, 4,000 IOPS and 100 MB/s of throughput Disk 3 - 1,024 GiBs, 15,000 IOPS and 1,200 MB/s of throughput The monthly cost for each Premium SSD v2 Disk, in a Locally Redundant Storage (LRS) configuration, in the East US region will be:

Disk 1 monthly cost = 64*$0.081 = $5.14/month Disk 2 monthly cost = 256*$0.081 + (4,000-3,000) * $0.0052 = $25.67/month Disk 3 monthly cost = 1,024*$0.081 + (15,000-3,000) * $0.0052 + (1,200 – 125) * $0.041 = $186.71/month Prices are subject to change depending on the region you choose.

If you still have any question on Azure pricing I would recommended to contact Billing and Subscription team would be the best to provide more insight and guidance on this scenario: https://azure.microsoft.com/en-us/support/options/ it's a free support

Additional information: If I use Azure Storage for only a few days a month, is the cost prorated?

Storage capacity is billed in units of the average daily amount of data stored, in gigabytes (GB), over a monthly period. For example, if you consistently used 10 GB of storage for the first half of the month, and none for the second half of the month, you would be billed for your average usage of 5 GB of storage.

0
Akash Kava On
  1. Azure disks are charged by the allocated size, if you create a disk with 128GB and use only 1GB, you are charged for full 128GB. You can't overuse, because if you need to store more information, you will have to increase size of disk, otherwise you will get no more free space error.
  2. There is no way to see how much of the disk is utilized, you have to login to the operating system of VM to find out. Since all data is allocated at once, Azure has no idea of what is stored or not, it is the OS which stores the information on the drive.
  3. Snapshot is a just a readonly copy of hard disk priced at or less same rate. However, incremental snapshots might have some less cost.
  4. Incremental snapshot is basically changes on top of first snapshot. You cannot create a non ultra disk from incremental snapshots of ultra disk. This may be because the incremental snapshots are features of ultra disk only, I don't think other disk types support it.