Nội dung chính Show Show
In this article, we’ll explain the concept of high availability and how to measure availability for IT systems. We’ll show how AWS can help you achieve high availability for cloud workloads, across compute, SQL databases and storage services. Read on to learn how Amazon’s Infrastructure as a Service (IaaS) capabilities such as elastic load balancing, availability zones and auto-scaling can help you achieve high availability for enterprise workloads. In this blog post, we’ll also examine how NetApp Cloud Volumes ONTAP can help to achieve highly available storage in AWS. In this article, you will learn:
What Is High Availability?Highly available systems are reliable in the sense that they continue operating even when critical components fail. They are also resilient, meaning that they are able to simply handle failure without service disruption or data loss, and seamlessly recover from such failure. High availability is commonly measured as a percentage of uptime. The number of “nines” is commonly used to indicate the degree of high availability. For example, “four nines” is indicative of a system that is up 99.99% of the time, meaning it is down for only 52.6 minutes during an entire year. The following elements help you implement highly available systems:
AWS helps you achieve high availability for cloud workloads, across three different dimensions:
AWS High Availability for EC2 InstancesIf you are running instances on Amazon EC2, Amazon provides several built-in capabilities to achieve high availability:
These capabilities are illustrated in the diagram below. The Elastic Load Balancer distributes traffic between two or more EC2 instances, each of which can potentially be deployed in a separate subnet that resides in a separate Amazon Availability Zone. These instances can be part of an Auto-Scaling Group, with additional instances launched on demand.  AWS High Availability for SQL Databases on Amazon RDSIf you are running an SQL database as part of your AWS application, you are probably running it using Amazon RDS. RDS provides high availability using Multi-Availability Zone (Multi-AZ) deployments. This means RDS automatically provisions a synchronous replica of the database in a different availability zone. When the main database instance goes down, users are redirected transparently to the other availability zone. This provides two levels of redundancy:
The following diagram illustrates Multi-AZ database deployment. Source: Amazon Web Services You can turn on this capability by specifying ‘Multi-AZ Deployment’ when creating an RDS database instance, either via the RDS Console or the Amazon CLI. Multi-AZ deployments are managed fully automatically, with no administrative intervention. Note that Multi-AZ deployment is not supported for read-only instances, and you should use read replicas to enable high availability for those instances. RDS provides the following capabilities per database type:
AWS High Availability for Storage ServicesHere is a brief summary of the high availability capabilities Amazon offers for other popular storage services: Amazon S3 Amazon EFS Amazon EBS Achieve High Availability in AWS with Cloud Volumes ONTAPNetApp Cloud Volumes ONTAP, the leading enterprise-grade storage management solution, delivers secure, proven storage management services on AWS, Azure and Google Cloud. The software-only service combines data control with enterprise-class storage features such as high availability, data protection, file share services, storage efficiencies, Kubernetes integration, and more. In this blog post, we looked into the high availability capabilities of AWS storage services. Using Cloud Volumes ONTAP, customers can leverage data protection and high availability, and operate non-disruptively while reducing the risks. Cloud Volumes ONTAP High Availability configuration will ensure business continuity with no data loss (RPO=0) and minimal recovery times (RTO < 60 secs). Cloud Volumes ONTAP high availability ensures your applications run smoothly 24/7. Through its dual-node configuration with synchronous replication, the solution provides 100% data integrity, enabling zero RPO and reduction of RTO below 60 seconds. Want to learn more about AWS high availability? Read our articles:AWS Availability Zones, Regions, & Placement Groups ExplainedBusiness organizations make use of applications that require different levels of availability and different SLA objectives. Learn how AWS Availability Zones, regions, multi-AZ deployments, and placement groups can help you improve availability and resilience for your workloads. Read AWS Availability Zones, Regions, & Placement Groups Explained to learn more. AWS GovCloud Services: Sensitive and Classified Data on the Public CloudAWS GovCloud is a separate AWS Region aimed for the use of USA government agencies, organizations working with the United States government, or projects that need to adhere to stringent standards or regulations. GovCloud helps users move sensitive workloads to the Amazon cloud, while adhering to their specific regulatory and compliance requirements. In addition to its special security and access capabilities, GovCloud is a regular Amazon region that provides all the basic Amazon services. Learn how AWS GovCloud services provide enhanced security for sensitive and classified data used by US government agencies and their partners and vendors. Read more: AWS GovCloud Services: Sensitive and Classified Data on the Public Cloud High Availability Cluster: Concepts and ArchitectureHigh availability clusters provide continuous availability. Learn how high availability clusters work, what concepts you should understand before adoption, and what are the most important requirements. Read more: High Availability Cluster: Concepts and Architecture Creating high availability systems in AWSMission-critical systems require a recovery point objective (RPO) of 0. Both cloud and on-premise storage solutions need to ensure no data is lost when an outage occurs. There are many solutions that can help you create highly available systems in the cloud. However, choosing and coordinating these services is challenging. Read How to Create High Availability Systems in AWS to Reach RPO 0 to learn about AWS high availability services and how they compare with Cloud Volumes ONTAP HA. Data redundant sitesEven after moving your workloads to AWS, the shared responsibility model states that you are responsible for some portions of your stored data. This means you need to ensure your secondary site has redundancy for data storage. Cloud Volumes ONTAP can help you deal with the challenges of creating data redundant sites in AWS. Cloud Volumes ONTAP allows you to easily create secondary copies of your on-premises deployments, and make sure that if one site fails, you can failover and failback between copies with no data loss. Read Data Redundancy with AWS and Cloud Volumes ONTAP to learn more. AWS high availability architectureAWS has a global infrastructure to provide high availability for cloud workloads. The key components of this architecture include:
Read Making the Most of AWS High Availability Architecture for Enterprise Workloads to learn more about availability zones, including best practices for AWS high availability. Setting Up Cloud Volumes ONTAP HA Configuration in Multiple Availability ZonesYou can deploy Cloud Volumes ONTAP HA for AWS in multiple AWS Availability Zones, to ensure high availability in case a single availability zone fails. Normally, Cloud Volumes ONTAP HA restricts access to one VPC. Read this guide to learn how to allow multiple VPCs to use the same Cloud Volumes ONTAP HA configuration. AWS Data Loss Prevention (DLP)DLP refers to tools and protocols used for protection against data loss or theft. Data loss can be caused by viruses and malware, power failures or insider threats. There are multiple approaches you can adopt to protect your data in AWS, all of which require security monitoring and a general understanding of security patterns. Common DLP patterns in AWS include:
To learn more about DLP approaches and tools in AWS read AWS Data Loss Prevention: Tools and Strategies. Maintaining Application Availability in the CloudKeeping applications up and running continuously is a major concern for enterprises. This requires not only taking steps to prevent downtime, but also recovering from failure as quickly as possible with minimal data loss. When relying solely on cloud service providers, enterprises struggle to reach near-zero recovery point objectives (RPO) and recovery time objectives (RTO). Attempting to meet these requirements with tools such as application layers, OS or databases often result in high costs, risks and complications. Cloud Volumes ONTAP high availability ensures your applications run smoothly 24/7. Through its dual-node configuration with synchronous replication, the solution provides 100% data integrity, enabling zero RPO and reduction of RTO below 60 seconds. Read Application Availability in the Cloud: Meeting the Challenges of High Availability and Continuous Operation to learn more. Windows Server Failover Clustering on AWS with NetApp Cloud Volumes ONTAPOne way that companies can ensure high availability in their data centers is with Windows Server Failover Clustering, also known as WSFC. By providing a native HA platform through By using Active / Passive servers with shared access to the same storage, WSFC provides applications with assured uptime. In this post we take an in-depth look at WSFC and its benefits for AWS HA when using Cloud Volumes ONTAP. Read more in Windows Server Failover Clustering on AWS with NetApp Cloud Volumes ONTAP See Our Additional Guides on Key IaaS TopicsWe have authored in-depth guides on several other topics that can also be useful as you explore the world of IaaS. Cloud MigrationLearn about cloud migration and what major challenges to expect when implementing a cloud migration strategy in your organization. See top articles in our cloud migration strategy guide:
AWS MigrationLearn about Amazon’s basic framework for migration, and how to plan for common challenges that affect almost every migration project. See top articles in our AWS migration guide:
AWS EBSLearn what is AWS EBS and how to perform common EBS operations. Including five highly useful EBS features that can help you optimize performance and billing. See top articles in our guide to AWS EBS:
AWS EFSLearn about AWS EFS, your backup options, how to optimize performance, see a brief comparison of EFS vs EBS vs S3, and discover how Cloud Volumes ONTAP can help. See top articles in our guide to AWS EFS:
Azure Cost ManagementLearn about tools and practices that can help you manage and optimize costs on the Microsoft Azure cloud. See top articles in our Azure cost management:
AWS Cost OptimizationLearn how AWS cost optimization works, free Amazon tools that can help manage costs, and best practices for reducing your cloud bill. See top articles in our AWS cost optimization guide:
Azure MigrationLearn about aspects of considerations when implementing Azure migration: migration models, state assessment, storage configuration, security, and maintenance. See top articles in our Azure migration guide:
Azure High AvailabilityHigh availability is one of the major benefits of cloud services. The guarantee that your data will remain accessible is critical to supporting high priority workloads and applications and is the reason many move to the cloud in the first place. This guide explains what high availability is and how to optimize Azure high availability. See top articles in our Azure high availability guide:
Linux on AzureLearn how to use Linux on Azure, including guides for cloud-based enterprise Linux deployments and performance tips. See top articles in our guide to Linux on Azure:
HPC on AzureDiscover services and techniques for cloud-based HPC, including unique Azure HPC features and use cases. See top articles in our guide to HPC on Azure:
SAP on AzureLearn about all SAP solutions offered as a service on Azure, including HANA, S/4HANA, NetWeaver and Hybris, migration considerations and best practices. See top articles in our guide to SAP on Azure:
VDI on AzureLearn what options are available for VDI on Azure. Understand how the architecture works and discover best practices for VDI deployments. See top articles in our guide to VDI on Azure:
AWS Big DataLearn about the tools AWS provides for building big data infrastructure, including data lakes and big data analytics systems. See top articles in our guide on AWS Big Data:
Google Cloud MigrationLearn how to migrate your workloads and data to Google Cloud, including in-depth comparisons between GCP and other cloud providers, tools, strategies, costs, and more. See top articles in our guide on Google Cloud migration:
Which of the following features of Amazon RDS allows for the offloading of database read activity?Which of the following Amazon RDS features facilitates offloading of database read activity? -Read Replicas (You can reduce the load on your source DB Instance by routing read queries from your applications to one or more read replicas. Which of the following features of Amazon RDS allows for better availability of databases choose the answer from the options given below?Amazon RDS Multi-AZ deployments provide enhanced availability and durability for database instances, making them a natural fit for production database workloads. When you provision a Multi-AZ database instance, Amazon RDS synchronously replicates your data to a standby instance in a different Availability Zone (AZ). Which RDS feature can best provide high availability in the event that the primary RDS database instance fails?Amazon RDS Multi-AZ with one standby Enhance availability by deploying a standby instance in a second AZ, and achieve fault tolerance in the event of an AZ or database instance failure. Which Amazon RDS features can be used to achieve high availability?Amazon Relational Database Service (Amazon RDS) supports two easy-to-use options for ensuring High Availability of your relational database. The Amazon Aurora PostgreSQL and Amazon Aurora MySQL engines include additional High Availability options. Which of the following features of Amazon RDS allows for the offloading of database read activity?Which of the following Amazon RDS features facilitates offloading of database read activity? -Read Replicas (You can reduce the load on your source DB Instance by routing read queries from your applications to one or more read replicas.
Which of the following database system is available on RDS?Amazon RDS gives you access to the capabilities of a familiar PostgreSQL, MySQL, MariaDB, Oracle, SQL Server , databases. In addition, Amazon Aurora, which is also part of RDS, has its own versions of Aurora MySQL and Aurora PostgreSQL.
Which of the following relational database service RDS features can help you achieve a monthly availability of 99.95 percent?With multi-AZ enabled, you can expect your database to achieve a monthly availability of 99.95 percent.
Which of the following is a database instance type offered by Amazon RDS?Amazon RDS supports three types of instance classes: general purpose, memory optimized, and burstable performance. For more information about Amazon EC2 instance types, see Instance types in the Amazon EC2 documentation. The following are the general-purpose DB instance types available: db.
|
