Azure Part 1- Interview Questions and Answers

❓What are the important Azure Storage services? 

🎤Answer - Azure offers several storage services that cater to different use cases and requirements. Some of the important Azure Storage services include:

1. Azure Blob Storage: Blob storage is optimized for storing massive amounts of unstructured data, such as text or binary data. It is suitable for serving images or documents directly to a browser.
2. Azure Files: Azure Files offers fully managed file shares in the cloud, accessible via the industry-standard Server Message Block (SMB) protocol. It's suitable for migrating existing applications that use file shares to Azure without significant changes.
3. Azure Disk Storage: Disk Storage provides durable and high-performance block storage for Azure Virtual Machines. It includes managed disks, which simplify disk management for VMs by handling disk availability and reliability.
4. Azure Queue Storage: Queue Storage is a messaging store for reliable messaging between application components. It is often used to decouple application components and to provide asynchronous communication.
5. Azure Table Storage: Table Storage is a NoSQL key-value store that's suitable for semi-structured data. It's well-suited for applications that require scalable and flexible data storage.
6. Azure Data Lake Storage: Data Lake Storage is a scalable and secure data lake solution for big data analytics. It integrates with Azure Synapse Analytics, Azure Databricks, and other analytics services.
7. Azure Archive Storage: Archive Storage is a low-cost, secure, and durable storage solution for rarely accessed data. It's suitable for data that needs to be retained for compliance or regulatory reasons.

These are some of the key Azure Storage services, each designed to address specific storage needs and scenarios. Depending on your requirements, you may use one or more of these services in combination to build robust and scalable storage solutions on Azure.

Primarily used containers as blob storage and data lake(ADLS Gen2) 

 ❓What is the difference between both of blob storage and data lake(ADLS Gen2)? 

🎤Answer - they serve different purposes and are optimized for different types of data and workloads. Here are some key differences between the two:

• Data Structure:

1. Blob Storage: Blob storage is optimized for storing large amounts of unstructured data, such as text or binary data. It does not enforce any schema on the stored data and is suitable for a wide variety of data types, including files, images, videos, logs, and backups.
2. Data Lake Storage Gen2: ADLS Gen2 is designed specifically for big data analytics workloads. It is a hierarchical file system that allows you to store both structured and unstructured data in a scalable and efficient manner. It provides features like directory structure, file-level security, and POSIX-style file and directory permissions.

• Storage Hierarchy:

1. Blob Storage: Blob storage uses containers to organize data. Containers can store a large number of blobs, and each blob can be accessed individually using its unique URL.
2. Data Lake Storage Gen2: ADLS Gen2 provides a hierarchical namespace that allows you to organize data into directories and subdirectories. This hierarchical structure makes it easier to manage and organize large amounts of data, especially in big data analytics scenarios.

• Access Control:

1. Blob Storage: Blob storage supports access control through Shared Access Signatures (SAS) and Azure Active Directory (Azure AD) authentication. You can control access at the container and blob level.
2. Data Lake Storage Gen2: ADLS Gen2 supports fine-grained access control through Azure AD authentication and POSIX-style access control lists (ACLs). You can set permissions at the directory, file, or even the individual file level.

• Optimization for Analytics:

1. Blob Storage: While Blob storage is suitable for storing large volumes of data, it may not be optimized for analytics workloads that require high-performance access to structured data.
2. Data Lake Storage Gen2: ADLS Gen2 is designed to handle big data analytics workloads efficiently. It provides features like optimized file formats (such as Parquet and ORC), integration with Azure Data Lake Analytics and Azure Databricks, and support for parallel processing.

❓What are the different ways to provide the access for storage account?

🎤Answer - In Azure, there are several ways to provide access to a storage account, each offering different levels of control and security. Here are the main ways to provide access to a storage account:

• Shared Access Signatures (SAS):

1. Shared Access Signatures (SAS) provide a secure way to grant limited access to resources in a storage account without sharing your account keys.
2. With SAS, you can specify the permissions (read, write, delete, list, etc.), the resources (containers, blobs, etc.), and the duration for which the access is granted.
3. SAS can be generated for both blob storage and file storage resources.

• Azure Role-Based Access Control (RBAC):

1. Azure RBAC allows you to assign roles to users, groups, or applications at the subscription, resource group, or individual resource level.
2. You can grant roles such as Storage Blob Data Contributor, Storage Account Contributor, or Storage Queue Data Contributor to control access to storage account resources.
3. RBAC provides fine-grained access control and integrates with Azure Active Directory (Azure AD) for identity and access management.

• Azure Active Directory (Azure AD) Authentication:

1. Azure Storage supports Azure AD authentication, allowing users and applications to authenticate using Azure AD credentials instead of storage account keys.
2. Azure AD authentication provides centralized identity management and eliminates the need to manage and distribute storage account keys.
3. You can grant access to Azure AD users, groups, or applications by assigning appropriate roles or permissions.

• Network-Based Access Control:

1. Azure Storage supports network-based access control to restrict access to storage accounts based on the network location.
2. You can use Virtual Network (VNet) service endpoints to allow access to storage accounts only from specified VNets or subnets.
3. Private endpoints enable you to access Azure Storage resources securely from within your VNet, without exposing them to the public internet.

• Azure Storage Firewalls and Virtual Networks:

1. Azure Storage Firewalls and Virtual Networks allow you to define network rules to control access to storage accounts based on IP addresses or IP address ranges.
2. You can configure rules to allow access from specific IP addresses or allow access only from selected virtual networks.
3. This feature helps secure your storage account by restricting access to trusted networks or IP addresses.

❓Why do you have two access keys for your storage account?

🎤Answer - Azure Storage accounts are provided with two access keys for enhanced security and ease of management. The primary reasons for having two access keys are:

• Key Rotation: Access keys have a long lifespan and are used for authentication and authorization to access Azure Storage resources. However, for security best practices, it's recommended to periodically rotate (change) the keys to minimize the risk of unauthorized access. 

• High Availability: Having two access keys enables you to achieve high availability and minimize downtime. If one key becomes compromised or needs to be rotated, you can use the second key to maintain access to your storage account without interruption. This ensures continuous availability of your storage resources and prevents service disruptions for your applications and users. 

• Ease of Management: Using two access keys simplifies key management tasks. You can maintain one key as the primary key and the other as the secondary key. You can use the primary key for day-to-day operations and use the secondary key for tasks such as key rotation, testing, or disaster recovery scenarios. This separation helps streamline key management processes and reduces the risk of accidental key exposure.

Having two access keys allows you to perform key rotation without disrupting access to your storage account. You can rotate one key at a time, ensuring that applications and services can continue to access the storage account using the other key. 

❓What factors affect the cost of storage account in Azure?

🎤Answer - The cost of an Azure Storage account can be influenced by several factors, including:

1. Storage Type: The type of storage used (e.g., blob storage, file storage, table storage, queue storage) affects the cost. For example, blob storage is priced differently from file storage.
2. Storage Capacity: The amount of data stored in the storage account (measured in GB or TB) directly impacts the cost. Azure charges for the amount of data stored, regardless of whether it's actively accessed or not.
3. Redundancy Options: Azure offers redundancy options such as -

• Locally Redundant Storage (LRS), Zone-Redundant Storage (ZRS), Geo-Redundant Storage (GRS), and Geo-Zone-Redundant Storage (GZRS). Each redundancy option has different pricing tiers, with higher redundancy levels generally costing more.

1. Data Transfer Costs: Costs may be incurred for data transferred in and out of the storage account, including ingress (data uploaded to Azure) and egress (data downloaded from Azure). Transfer costs vary based on the region, data type, and volume of data transferred.
2. Operations (Transactions): Azure Storage accounts incur charges for various operations performed on data, such as reading, writing, listing, and deleting data objects (e.g., blobs, files, tables). The number and type of operations performed affect the overall cost.
3. Data Retrieval Patterns: For services like Azure Blob Storage, where access tiers are available (e.g., hot, cool, archive), the data retrieval patterns and access frequency influence the cost. Data stored in the hot tier is more expensive to access than data stored in the cool or archive tiers.
4. Lifecycle Management: Azure Storage offers features like lifecycle management and object versioning, which may impact costs depending on how they are configured. For example, automatically transitioning data to a cheaper storage tier after a certain period can help reduce costs.
5. Network Bandwidth: Data transfer costs may also depend on network bandwidth usage, especially when accessing storage from outside the Azure region or transferring data between Azure regions.
6. Compliance and Security Requirements: Additional costs may be incurred for features such as encryption, compliance certifications (e.g., GDPR, HIPAA), and security measures (e.g., access control, auditing) to meet specific regulatory or security requirements.
7. Reserved Capacity: Azure offers reserved capacity options that provide discounts for committing to a specific amount of storage capacity or performance in advance. Choosing reserved capacity can lead to cost savings compared to pay-as-you-go pricing.

❓What is the main differences between Standard and Premium storage account types in Azure?

🎤Answer - The main differences between Standard and Premium storage account types in Azure lie in their performance characteristics, availability options, and supported features:

• Performance:

1. Standard Storage: Standard storage accounts offer standard HDD (Hard Disk Drive) storage, which provides cost-effective storage with moderate performance characteristics. Standard storage is suitable for general-purpose workloads that do not require high I/O (Input/Output) performance.
2. Premium Storage: Premium storage accounts provide high-performance SSD (Solid State Drive) storage, which offers low-latency and high-throughput storage optimized for I/O-intensive workloads. Premium storage is ideal for mission-critical applications, databases, and workloads that require high-performance storage.

• Availability:

1. Standard Storage: Standard storage accounts support locally redundant storage (LRS) and geo-redundant storage (GRS) redundancy options. LRS replicates data within the same datacenter, while GRS replicates data to a secondary datacenter in a different geographic region for additional redundancy.
2. Premium Storage: Premium storage accounts support only locally redundant storage (LRS) redundancy. This means that data is replicated within the same datacenter for high availability but does not have the additional redundancy of geo-replication.

• Feature Support:

1. Standard Storage: Standard storage accounts support features such as Azure Blob Storage, Azure File Storage, Azure Table Storage, and Azure Queue Storage. They are suitable for a wide range of general-purpose storage needs.
2. Premium Storage: Premium storage accounts primarily support Azure Managed Disks, which provide high-performance block storage for Azure Virtual Machines (VMs). They are optimized for VM workloads that require low-latency storage and high I/O performance.

• Cost:

1. Standard Storage: Standard storage accounts typically have lower storage costs compared to premium storage accounts. They are suitable for workloads that do not require the high-performance characteristics of premium storage.
2. Premium Storage: Premium storage accounts have higher storage costs due to the premium SSD storage. They are ideal for workloads that demand high-performance storage and require low-latency access to data.

❓Should we choose the region with the lowest price?

🎤Answer - Choosing the region with the lowest price solely based on pricing might not always be the best approach. While pricing is an important factor to consider, there are other factors to take into account when selecting a region for your Azure resources:

1. Latency: The physical distance between your users and the Azure datacenter can impact latency. Choosing a region closer to your users can result in lower latency and better performance for your applications.
2. Compliance and Data Residency: Some industries and regions have specific compliance requirements regarding data residency and sovereignty. You may need to choose a region that complies with these regulations.
3. Availability and Redundancy: Azure regions have different levels of availability and redundancy. Some regions may offer more availability zones or paired regions for disaster recovery. Choosing a region with high availability and redundancy can help ensure the reliability of your applications.
4. Feature Availability: Some Azure services and features may not be available in all regions. Before choosing a region, ensure that it supports all the services and features you require for your applications.
5. Cost: While pricing is important, it's essential to consider the overall cost of running your applications in a particular region, including data transfer costs, storage costs, and other associated costs.
6. Support and SLAs: Azure provides support and service level agreements (SLAs) for its regions. Choosing a region with strong support and SLAs can help ensure that you receive timely assistance and meet your uptime requirements.
7. Future Growth: Consider your future growth plans and whether the region can accommodate your scaling needs. Choosing a region with room for expansion can save you from having to migrate to a different region later.

❓What are the access tiers provided by Azure Blob Storage?

🎤Answer - Access tiers in Azure Blob Storage provide flexibility and cost optimization options for managing your data based on its access patterns and frequency, helping you balance cost-effectiveness with performance requirements. Azure Blob Storage offers the following access tiers:

• Hot Access Tier:

1. The Hot access tier is optimized for frequently accessed data that requires low-latency access and high-performance storage.
2. Data stored in the Hot access tier is immediately available for read and write operations.
3. This tier is suitable for data that requires frequent access and fast response times, such as active workloads, frequently accessed files, or recent backups.

• Cool Access Tier:

1. The Cool access tier is designed for data that is accessed less frequently but still requires quick access when needed.
2. Data stored in the Cool access tier has lower storage costs compared to the Hot access tier but may have slightly higher access costs.
3. This tier is suitable for data with infrequent access patterns, such as archival data, backups, or historical records.

• Archive Access Tier:

1. The Archive access tier is optimized for long-term storage of rarely accessed data at the lowest cost.
2. Data stored in the Archive access tier has the lowest storage costs but incurs higher access costs and longer access times compared to the Hot and Cool tiers.
3. This tier is suitable for data that is rarely accessed and can tolerate longer retrieval times, such as compliance data, regulatory archives, or long-term backups.

Key points to note about access tiers:

1. You can set the access tier at the blob level during or after data upload, allowing you to optimize storage costs based on the access patterns of individual blobs.
2. Azure Blob Storage provides lifecycle management policies that automatically transition data between access tiers based on specified criteria, such as time since last access or blob age.
3. Access tier transitions may incur data movement costs and may take some time to complete, especially when transitioning data to or from the Archive access tier.
4. You can monitor and analyze access patterns using Azure Storage Metrics and Azure Storage Analytics to optimize your storage costs and performance over time.

Please visit the next sections - Azure Part 1- Interview Questions and Answers

To learn more, please follow us - 🔊 http://www.sql-datatools.com To Learn more, please visit our YouTube channel at — 🔊 http://www.youtube.com/c/Sql-datatools To Learn more, please visit our Instagram account at - 🔊 https://www.instagram.com/asp.mukesh/ To Learn more, please visit our twitter account at - 🔊 https://twitter.com/macxima