Choose right disk Storage Account

Question 1

What are the disk roles

Answer 1

OS, Data Disk, Temporary disk

Question 2

OS disk

Answer 2

One disk in each virtual machine contains the operating system files. When you create a virtual machine, you select a virtual machine image and that fixes the operating system and the OS disk that’s attached to the new machine. The OS disk has a maximum capacity of 2,048 GB

Question 3

Data disk

Answer 3

You can add one or more data virtual disks to each virtual machine to store data. For example, database files, website static content, or custom application code should be stored on data disks. The number of data disks you can add depends on the virtual machine size. Each data disk has a maximum capacity of 32,767 GB

Question 4

Temporary disk

Answer 4

Each virtual machine contains a single temporary disk, which is used for short-term storage applications such as page files and swap files. The contents of temporary disks are lost during maintenance events, so don’t use these disks for critical data. These disks are local to the server and aren’t stored in a storage account.

Question 5

Ephemeral OS disks

Answer 5

An ephemeral OS disk is a virtual disk that saves data on the local virtual machine storage. An ephemeral disk has faster read-and-write latency than a managed disk. It’s also faster to reset the image to the original boot state if you’re using an ephemeral disk. However, an individual virtual machine failure might destroy all the data on an ephemeral disk and leave the virtual machine unable to boot. Because ephemeral disks reside locally to the host, they incur no storage costs and are free.

Question 6

Managed disks

Answer 6

Most disks that you use with virtual machines in Azure are managed disks. A managed disk is a virtual hard disk for which Azure manages all the required physical infrastructure. Because Azure takes care of the underlying complexity, managed disks are easy to use. You can just provision them and attach them to virtual machines.

Question 7

Simple scalability

Answer 7

You can create up to 50,000 managed disks of each type in each region in your subscription

Question 8

High availability

Answer 8

Managed disks support 99.999% availability by storing data three times. If there’s a failure in one replica, the other two can maintain full read-write functionality.

Question 9

Integration with availability sets and zones

Answer 9

If you place your virtual machines into an availability set, Azure automatically distributes the managed disks for those machines into different fault domains so that your machines are resilient to localized failures. You can also use availability zones, which distribute data across multiple datacenters, for even greater availability.

Question 10

Support for Azure Backup

Answer 10

Azure Backup natively supports managed disks, which includes encrypted disks.
Granular access control. You can use Azure role-based access control (RBAC) to grant access to specific user accounts for specific operations on a managed disk. For example, you could ensure that only an administrator can delete a disk.

Question 11

Support for encryption

Answer 11

o protect sensitive data on a managed disk from unauthorized access, you can encrypt it by using Azure Storage Service Encryption (SSE), which is provided with Azure Storage accounts. Alternatively, you can use Azure Disk Encryption (ADE), which uses BitLocker for Windows virtual machines, and DM-Crypt for Linux virtual machines.

Question 12

Unmanaged disks

Answer 12

An unmanaged disk, like a managed disk, is stored as a page blob in an Azure Storage account. The difference is that with unmanaged disks, you create and maintain this storage account manually.