{"id":23374,"date":"2017-04-18T19:48:19","date_gmt":"2017-04-18T19:48:19","guid":{"rendered":"https:\/\/www.whizlabs.com\/?p=23374"},"modified":"2024-05-16T16:52:42","modified_gmt":"2024-05-16T11:22:42","slug":"aws-ec2-highavailability","status":"publish","type":"post","link":"https:\/\/www.whizlabs.com\/blog\/aws-ec2-highavailability\/","title":{"rendered":"AWS Certification : High availability of EC2 instances using AutoScaling"},"content":{"rendered":"<p><span lang=\"EN-US\">Are<\/span><span lang=\"EN-US\"> you preparing for\u00a0<\/span><a href=\"https:\/\/www.whizlabs.com\/aws-sysops-administrator-associate\/\"><span lang=\"EN-US\">AWS Certified SysOps Administrator \u2013 Associate certification exam<\/span><\/a><span lang=\"EN-US\">? \u00a0Are you ready to pass this exam? In this blog, we are writing a series of articles on topics which are covered in the AWS certified SysOps associate certification exam. You can subscribe to us for receiving further updates on this topic.<\/span><\/p>\n<p><span lang=\"EN-US\">The SysOps Associate certification exam is the hardest exam in the associate level. We would recommend you pass both <a title=\"AWS Certified Solutions Architect Associate \u2013 Practice Tests\" href=\"https:\/\/www.whizlabs.com\/aws-solutions-architect-associate\/practice-tests\/\">solution architect associated certification exam<\/a> and <a title=\"AWS Certified Developer Associate \u2013 Practice Tests\" href=\"https:\/\/www.whizlabs.com\/aws-developer-associate\/practice-tests\/\">developer associated certification exam<\/a> first before of taking take this exam.<\/span><\/p>\n<p style=\"text-align: left;\" align=\"center\">The AWS Certified SysOps Administrator \u2013 Associate exam validates technical expertise in deployment, management, and operations on the AWS platform.<\/p>\n<ul type=\"disc\">\n<li><b><span lang=\"EN-US\">TRY\u00a0NOW :\u00a0<\/span><\/b><a title=\"AWS Certified SysOps Administrator Associate \u2013 Free Test\" href=\"https:\/\/www.whizlabs.com\/aws-sysops-administrator-associate\/free-test\/\"><b><span lang=\"EN-US\">10 Free Practice Questions for SysOps Associate Exam<\/span><\/b><\/a><\/li>\n<li><b><span lang=\"EN-US\">OFFER :\u00a0<\/span><\/b><a title=\"AWS Certified SysOps Administrator Associate\" href=\"https:\/\/www.whizlabs.com\/aws-sysops-administrator-associate\/\"><b><span lang=\"EN-US\">420 Practice Questions for SysOps Associate Exam (50% Discount)<\/span><\/b><\/a><\/li>\n<\/ul>\n<p><span lang=\"EN-US\">The <a href=\"https:\/\/www.whizlabs.com\/aws-sysops-administrator-associate\/\" target=\"_blank\" rel=\"noopener\">AWS SysOps Administrator<\/a> \u2013 Associate Level exam validates the candidate\u2019s ability to:<\/span><\/p>\n<ul type=\"disc\">\n<li><span lang=\"EN-US\">Deliver the stability and scalability needed by a business on AWS<\/span><\/li>\n<li><span lang=\"EN-US\">Provision systems,\u00a0services\u00a0and deployment automation on AWS<\/span><\/li>\n<li><span lang=\"EN-US\">Ensure data integrity and data security on AWS technology<\/span><\/li>\n<li><span lang=\"EN-US\">Provide guidance on AWS best practices<\/span><\/li>\n<li><span lang=\"EN-US\">Understand and monitor metrics on AWS<\/span><\/li>\n<\/ul>\n<div><\/div>\n<div>\n<figure id=\"attachment_23164\" aria-describedby=\"caption-attachment-23164\" style=\"width: 654px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/www.whizlabs.com\/blog\/wp-content\/uploads\/2024\/05\/Figure0_SysOpsBlueprint.png\"><img decoding=\"async\" class=\"wp-image-23164 size-full\" src=\"https:\/\/www.whizlabs.com\/blog\/wp-content\/uploads\/2024\/05\/Figure0_SysOpsBlueprint.png\" alt=\"Domains covered\" width=\"654\" height=\"545\" \/><\/a><figcaption id=\"caption-attachment-23164\" class=\"wp-caption-text\">Domains covered at the AWS Certified SysOps associate exam<\/figcaption><\/figure>\n<p align=\"center\"><b><i><span lang=\"EN-US\">Figure #0. \u00a0Domains covered\u00a0at\u00a0the AWS Certified SysOps associate exam<\/span><\/i><\/b><\/p>\n<\/div>\n<p><span lang=\"EN-US\">You can download the related\u00a0<\/span><a href=\"http:\/\/awstrainingandcertification.s3.amazonaws.com\/production\/AWS_certified_sysops_associate_blueprint.pdf\" target=\"_blank\" rel=\"noopener noreferrer\"><span lang=\"EN-US\">AWS Certified SysOps Administrator \u2013 Associate Level Exam Blueprint<\/span><\/a><span lang=\"EN-US\">\u00a0for more detail about it.<\/span><\/p>\n<p><span lang=\"EN-US\">In this article, we are going to explain about the topic that addresses the scalability and elasticity of EC2 instances as highlighted in the AWS Blueprint from the above exam guide.<\/span><\/p>\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_76 ez-toc-wrap-left counter-hierarchy ez-toc-counter ez-toc-custom ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">Table of Contents<\/p>\n<span class=\"ez-toc-title-toggle\"><a href=\"#\" class=\"ez-toc-pull-right ez-toc-btn ez-toc-btn-xs ez-toc-btn-default ez-toc-toggle\" aria-label=\"Toggle Table of Content\"><span class=\"ez-toc-js-icon-con\"><span class=\"\"><span class=\"eztoc-hide\" style=\"display:none;\">Toggle<\/span><span class=\"ez-toc-icon-toggle-span\"><svg style=\"fill: #ea7e02;color:#ea7e02\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" class=\"list-377408\" width=\"20px\" height=\"20px\" viewBox=\"0 0 24 24\" fill=\"none\"><path d=\"M6 6H4v2h2V6zm14 0H8v2h12V6zM4 11h2v2H4v-2zm16 0H8v2h12v-2zM4 16h2v2H4v-2zm16 0H8v2h12v-2z\" fill=\"currentColor\"><\/path><\/svg><svg style=\"fill: #ea7e02;color:#ea7e02\" class=\"arrow-unsorted-368013\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"10px\" height=\"10px\" viewBox=\"0 0 24 24\" version=\"1.2\" baseProfile=\"tiny\"><path d=\"M18.2 9.3l-6.2-6.3-6.2 6.3c-.2.2-.3.4-.3.7s.1.5.3.7c.2.2.4.3.7.3h11c.3 0 .5-.1.7-.3.2-.2.3-.5.3-.7s-.1-.5-.3-.7zM5.8 14.7l6.2 6.3 6.2-6.3c.2-.2.3-.5.3-.7s-.1-.5-.3-.7c-.2-.2-.4-.3-.7-.3h-11c-.3 0-.5.1-.7.3-.2.2-.3.5-.3.7s.1.5.3.7z\"\/><\/svg><\/span><\/span><\/span><\/a><\/span><\/div>\n<nav><ul class='ez-toc-list ez-toc-list-level-1 ' ><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-1\" href=\"https:\/\/www.whizlabs.com\/blog\/aws-ec2-highavailability\/#Context\" >Context<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/www.whizlabs.com\/blog\/aws-ec2-highavailability\/#What_is_Auto_Scaling\" >What is Auto Scaling?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/www.whizlabs.com\/blog\/aws-ec2-highavailability\/#Benefits_of_Auto_Scaling\" >Benefits of Auto Scaling<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/www.whizlabs.com\/blog\/aws-ec2-highavailability\/#Creating_Auto_Scaling_Groups\" >Creating Auto Scaling Groups<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/www.whizlabs.com\/blog\/aws-ec2-highavailability\/#Auto_Scaling_Group_Lifecycle\" >Auto Scaling Group Lifecycle<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/www.whizlabs.com\/blog\/aws-ec2-highavailability\/#Detecting_%E2%80%9CUnhealthy%E2%80%9D_instances\" >Detecting \u201cUnhealthy\u201d instances<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/www.whizlabs.com\/blog\/aws-ec2-highavailability\/#Distributing_traffic_between_EC2_instances\" >Distributing traffic between EC2 instances<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/www.whizlabs.com\/blog\/aws-ec2-highavailability\/#Important_Points_to_Remember_for_the_AWS_Certified_SysOps_Administrator_%E2%80%93_Associate_Certification_exam\" >Important Points to Remember for the AWS Certified SysOps Administrator \u2013 Associate Certification exam<\/a><\/li><\/ul><\/nav><\/div>\n<h2><span class=\"ez-toc-section\" id=\"Context\"><\/span><span lang=\"EN-US\">Context<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><span lang=\"EN-US\">Almost every day and depending of our company needs, we must maintain the availability and elasticity required into our infrastructure services, permitting that it scales up or down automatically according to some conditions that we define, contributing to improve their performance or reduce their cost.<\/span><\/p>\n<h2><span class=\"ez-toc-section\" id=\"What_is_Auto_Scaling\"><\/span><span lang=\"EN-US\">What is Auto Scaling?<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><i><span lang=\"EN-US\">Auto Scaling<\/span><\/i><span lang=\"EN-US\"> is a fully managed service designed to launch or terminate Amazon EC2 instances automatically to help ensure you have the adequate number instances available for handling your application\u2019s load.<\/span><\/p>\n<p><span lang=\"EN-US\">Auto Scaling detects impaired EC2 instances and unhealthy applications, and replace the instances without your intervention, this service scales your EC2 capacity up or down according to conditions defined. This ensures that your application is getting the compute capacity that you expect, maintain performance and decrease capacity during low demand to reduce costs.<\/span><\/p>\n<p><span lang=\"EN-US\">As SysOps administrator, you can <\/span><span lang=\"EN-US\">reduce the need to manually provision Amazon EC2 capacity in advance<\/span> if you use Auto Scaling features.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Benefits_of_Auto_Scaling\"><\/span><span lang=\"EN-US\">Benefits of Auto Scaling<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><span lang=\"EN-US\">When you use Auto Scaling, your applications gain the following benefits<\/span>:<\/p>\n<ul>\n<li><b><span lang=\"EN-US\">Better fault tolerance<\/span><\/b><span lang=\"EN-US\">: Auto Scaling can detect when an instance is unhealthy, terminate it, and launch an instance to replace it. Maintain a fixed group size or adjust dynamically based on Amazon <i>Cloud Watch<\/i><\/span><\/li>\n<li><b><span lang=\"EN-US\">Better availability<\/span><\/b><span lang=\"EN-US\">: Auto Scaling can help you ensure that your application always has the right amount of capacity to handle the current traffic demands.<\/span> <span lang=\"EN-US\">Keep your Auto Scaling group healthy and balanced.<\/span><\/li>\n<li><b><span lang=\"EN-US\">Better cost management<\/span><\/b><span lang=\"EN-US\">: Auto Scaling can dynamically increase and decrease capacity as needed. You just pay for the EC2 instances that you use.<\/span><\/li>\n<li><b><span lang=\"EN-US\">Reusable Instance Templates:<\/span><\/b><span lang=\"EN-US\"> Provision instances based on a reusable template you define, called a launch configuration<\/span><\/li>\n<\/ul>\n<h2><span class=\"ez-toc-section\" id=\"Creating_Auto_Scaling_Groups\"><\/span><span lang=\"EN-US\">Creating Auto Scaling Groups<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><span lang=\"EN-US\">You create collections of EC2 instances, called\u00a0<i>Auto Scaling groups, <\/i>and define the limits of group size:<\/span><\/p>\n<ul>\n<li><i><span lang=\"EN-US\">Minimum size<\/span><\/i><span lang=\"EN-US\">: lower limit of number instances into the group size <\/span><\/li>\n<li><i><span lang=\"EN-US\">Maximum size<\/span><\/i><span lang=\"EN-US\">: higher limit of number instances into the group size <\/span><\/li>\n<li><i><span lang=\"EN-US\">Desired capacity<\/span><\/i><span lang=\"EN-US\">: number of instances should be running into a specific time<\/span><\/li>\n<\/ul>\n<figure id=\"attachment_23693\" aria-describedby=\"caption-attachment-23693\" style=\"width: 310px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/www.whizlabs.com\/blog\/wp-content\/uploads\/2024\/05\/Figure1_AutoScalingGroupsize.png\"><img decoding=\"async\" class=\"wp-image-23693 size-full\" src=\"https:\/\/www.whizlabs.com\/blog\/wp-content\/uploads\/2024\/05\/Figure1_AutoScalingGroupsize.png\" alt=\"Auto Scaling group size limits\" width=\"310\" height=\"224\" \/><\/a><figcaption id=\"caption-attachment-23693\" class=\"wp-caption-text\">Auto Scaling group size limits<\/figcaption><\/figure>\n<p align=\"center\"><b><i>\u00a0<\/i><\/b><em><strong>Figure #1. Auto Scaling group size limits<\/strong><\/em><\/p>\n<p>&nbsp;<\/p>\n<p><span lang=\"EN-US\">To create an <i>Auto Scaling group<\/i>, you will first need to choose a template that your <i>Auto Scaling group<\/i> will use when it launches instances for you, called a <i>launch configuration<\/i>. Choose <i>a launch configuration<\/i> or create a new one, and then apply it to your group.<\/span><\/p>\n<p><b><span lang=\"EN-US\">Step 1: Create launch configuration<\/span><\/b><\/p>\n<p><span lang=\"EN-US\">First, define a template that your Auto Scaling group will use to launch instances. You can change your group&#8217;s launch configuration at any time.<\/span><\/p>\n<figure id=\"attachment_23695\" aria-describedby=\"caption-attachment-23695\" style=\"width: 1024px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/www.whizlabs.com\/blog\/wp-content\/uploads\/2024\/05\/Figure2_LaunchConfiguration.png\"><img decoding=\"async\" class=\"wp-image-23695 size-large\" src=\"https:\/\/www.whizlabs.com\/blog\/wp-content\/uploads\/2024\/05\/Figure2_LaunchConfiguration.png\" alt=\"Creating a Launch Configuration into an Auto Scaling Group\" width=\"1024\" height=\"492\" \/><\/a><figcaption id=\"caption-attachment-23695\" class=\"wp-caption-text\">Creating a Launch Configuration into an Auto Scaling Group<\/figcaption><\/figure>\n<p style=\"text-align: center;\" align=\"center\"><b><i><span lang=\"EN-US\">Figure #2. \u00a0Creating a Launch Configuration into an Auto Scaling Group<\/span><\/i><\/b><\/p>\n<p><b><span lang=\"EN-US\">Step 2: Create Auto Scaling group<\/span><\/b><\/p>\n<p><span lang=\"EN-US\">Next, give your group a name and specify how many instances you want to run in it.<\/span><\/p>\n<figure id=\"attachment_23696\" aria-describedby=\"caption-attachment-23696\" style=\"width: 1024px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/www.whizlabs.com\/blog\/wp-content\/uploads\/2024\/05\/Figure3_AutoScalingGroup.png\"><img decoding=\"async\" class=\"wp-image-23696 size-large\" src=\"https:\/\/www.whizlabs.com\/blog\/wp-content\/uploads\/2024\/05\/Figure3_AutoScalingGroup.png\" alt=\"Creating an Auto Scaling Group\" width=\"1024\" height=\"533\" \/><\/a><figcaption id=\"caption-attachment-23696\" class=\"wp-caption-text\">Creating an Auto Scaling Group<\/figcaption><\/figure>\n<p align=\"center\"><b><i><span lang=\"EN-US\">Figure #3. \u00a0Creating an Auto Scaling Group<\/span><\/i><\/b><\/p>\n<p><span lang=\"EN-US\">Your group will maintain this number of instances and replace any that become unhealthy or impaired.<br \/>\nYou can also use <i>Amazon CloudWatch<\/i> to send alarms to trigger scaling activities and <i>Elastic Load Balancing<\/i> (ELB) to distribute traffic to your instances within Auto Scaling groups. If you have predictable load changes, you can set a schedule through Auto Scaling to plan your scaling activities, avoid create schedules that make conflict.<\/span><\/p>\n<figure id=\"attachment_23699\" aria-describedby=\"caption-attachment-23699\" style=\"width: 1024px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/www.whizlabs.com\/blog\/wp-content\/uploads\/2024\/05\/Figure4_ScheduleAction.png\"><img decoding=\"async\" class=\"wp-image-23699 size-large\" src=\"https:\/\/www.whizlabs.com\/blog\/wp-content\/uploads\/2024\/05\/Figure4_ScheduleAction.png\" alt=\"Creating a Scheduled Action for Auto Scaling Group\" width=\"1024\" height=\"539\" \/><\/a><figcaption id=\"caption-attachment-23699\" class=\"wp-caption-text\">Creating a Scheduled Action for Auto Scaling Group<\/figcaption><\/figure>\n<p align=\"center\"><b><i><span lang=\"EN-US\">Figure #4. \u00a0Creating a Scheduled Action for Auto Scaling Group<\/span><\/i><\/b><\/p>\n<p><span lang=\"EN-US\">Auto Scaling enables you to take advantage of the safety and reliability of geographic redundancy by spanning Auto Scaling groups across multiple Availability Zones within a region. When one Availability Zone becomes unhealthy or unavailable, Auto Scaling launches new instances in an unaffected Availability Zone.<\/span><\/p>\n<p><span lang=\"EN-US\">Balancing resources across Availability Zones is a best practice for well-architected applications, as this greatly increases aggregate system availability. Auto Scaling automatically balances EC2 instances across zones when you configure multiple zones in your Auto Scaling group settings.<\/span><\/p>\n<h2><span class=\"ez-toc-section\" id=\"Auto_Scaling_Group_Lifecycle\"><\/span><span lang=\"EN-US\">Auto Scaling Group Lifecycle<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><span lang=\"EN-US\">\u00a0<\/span>The lifecycle starts when the Auto Scaling group launches an instance and puts it into service. The lifecycle ends when you terminate the instance, or the Auto Scaling group takes the instance out of service and terminates it.<\/p>\n<figure id=\"attachment_23702\" aria-describedby=\"caption-attachment-23702\" style=\"width: 519px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/www.whizlabs.com\/blog\/wp-content\/uploads\/2024\/05\/Figure5_AutoScalingLifecycle.png\"><img decoding=\"async\" class=\"wp-image-23702 size-full\" src=\"https:\/\/www.whizlabs.com\/blog\/wp-content\/uploads\/2024\/05\/Figure5_AutoScalingLifecycle.png\" alt=\"The complete lifecycle of instances in an Auto Scaling group\" width=\"519\" height=\"399\" \/><\/a><figcaption id=\"caption-attachment-23702\" class=\"wp-caption-text\">The complete lifecycle of instances in an Auto Scaling group<\/figcaption><\/figure>\n<p align=\"center\"><b><i><span lang=\"EN-US\">Figure #5. \u00a0The complete lifecycle of instances in an Auto Scaling group<\/span><\/i><\/b><\/p>\n<p>You can add a lifecycle hook to your Auto Scaling group so that you can perform custom actions when instances launch or terminate. Adding lifecycle hooks to your Auto Scaling group gives you greater control over how instances launch and terminate. For example, you could install or configure software on newly launched instances, or download log files from an instance before it terminates.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Detecting_%E2%80%9CUnhealthy%E2%80%9D_instances\"><\/span><span lang=\"EN-US\">Detecting \u201cUnhealthy\u201d instances<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><span lang=\"EN-US\">An <i>unhealthy instance<\/i> is one where the hardware has become impaired for some reason (bad disk, etc.), or it is not passing a user-configured ELB health check. Auto Scaling performs health checks on each individual EC2 instance at regular intervals, and if the instance is connected to an Elastic Load Balancing load balancer, it can also perform ELB health checks.<\/span><\/p>\n<figure id=\"attachment_23704\" aria-describedby=\"caption-attachment-23704\" style=\"width: 1299px\" class=\"wp-caption aligncenter\"><a href=\"https:\/\/www.whizlabs.com\/blog\/wp-content\/uploads\/2024\/05\/Figure6_UnhealthyInstances.png\"><img decoding=\"async\" class=\"wp-image-23704 size-full\" src=\"https:\/\/www.whizlabs.com\/blog\/wp-content\/uploads\/2024\/05\/Figure6_UnhealthyInstances.png\" alt=\"An Unhealthy instance into the Auto Scaling Group\" width=\"1299\" height=\"368\" \/><\/a><figcaption id=\"caption-attachment-23704\" class=\"wp-caption-text\">An Unhealthy instance into the Auto Scaling Group<\/figcaption><\/figure>\n<p align=\"center\"><b><i><span lang=\"EN-US\">Figure #6.\u00a0 An Unhealthy instance into the Auto Scaling Group<\/span><\/i><\/b><\/p>\n<p><span lang=\"EN-US\">Auto Scaling might suspend processes for Auto Scaling groups that repeatedly fail to launch instances. This is known as an administrative suspension, and most commonly applies to Auto Scaling groups that have been trying to launch instances for over 24 hours but have not succeeded in launching any instances.<\/span><\/p>\n<h2><span class=\"ez-toc-section\" id=\"Distributing_traffic_between_EC2_instances\"><\/span><span lang=\"EN-US\">Distributing traffic between EC2 instances<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><span lang=\"EN-US\">To use a load balancer with your Auto Scaling group, create the load balancer and then attach it to the group.<\/span><\/p>\n<p><span lang=\"EN-US\">If you are preparing for the <a href=\"https:\/\/www.whizlabs.com\/aws-solutions-architect-associate\/\" target=\"_blank\" rel=\"noopener\">AWS associate<\/a> certifications exam and looking for any help, please send us a mail to call our customer support team. And Benchmark your AWS knowledge with one or more of the highly demanded <a href=\"https:\/\/www.whizlabs.com\/aws-certifications\/\" target=\"_blank\" rel=\"noopener\">AWS Foundation certifications<\/a>.<\/span><\/p>\n<h2><span class=\"ez-toc-section\" id=\"Important_Points_to_Remember_for_the_AWS_Certified_SysOps_Administrator_%E2%80%93_Associate_Certification_exam\"><\/span><span lang=\"EN-US\">Important Points to Remember for the AWS Certified SysOps Administrator \u2013 Associate Certification exam<\/span><span class=\"ez-toc-section-end\"><\/span><\/h2>\n<ul type=\"disc\">\n<li><span lang=\"EN-US\">Auto Scaling is a web service designed to launch or terminate Amazon EC2 instances automatically based on user-defined policies, schedules, and health checks<\/span><\/li>\n<li><span lang=\"EN-US\">Some benefits for using Auto Scaling: Automated provisioning, adjustable capacity, and reusable instance templates.<\/span><\/li>\n<li><span lang=\"EN-US\">There are no additional fees with Auto Scaling<\/span><\/li>\n<li><span lang=\"EN-US\">You could enable CloudWatch detailed monitoring when creating a launch configuration<\/span><\/li>\n<li><span lang=\"EN-US\">Auto Scaling performs health checks per EC2 instance at regular intervals or by an ELB health check configured<\/span><\/li>\n<li><span lang=\"EN-US\">You should span your Auto Scaling groups across multiple Availability Zones within a region to obtain more safety and reliability, it\u2019s a best practice<\/span><\/li>\n<li><span lang=\"EN-US\">The Auto Scaling group has a lifecycle and you can add Auto Scaling <i>lifecycle hooks<\/i> to perform custom actions<\/span><\/li>\n<li><span lang=\"EN-US\">You can set a schedule through Auto Scaling to plan your scaling activities<\/span>, please avoid schedules that make conflict<\/li>\n<\/ul>\n<p><b><span lang=\"EN-US\">Glossary<\/span><\/b><\/p>\n<table border=\"1\" cellspacing=\"0\" cellpadding=\"0\">\n<tbody>\n<tr>\n<td valign=\"top\" width=\"174\"><b><span lang=\"EN-US\">Term<\/span><\/b><\/td>\n<td valign=\"top\" width=\"449\"><b><span lang=\"EN-US\">Brief description<\/span><\/b><\/td>\n<\/tr>\n<tr>\n<td valign=\"top\" width=\"174\"><\/td>\n<td valign=\"top\" width=\"449\"><\/td>\n<\/tr>\n<tr>\n<td valign=\"top\" width=\"174\"><span lang=\"EN-US\">Auto Scaling group<\/span><\/td>\n<td valign=\"top\" width=\"449\"><span lang=\"EN-US\">An <i>Auto Scaling group<\/i> contains a collection of EC2 instances that share similar characteristics and are treated as a logical grouping for the purposes of instance scaling and management<\/span><span lang=\"EN-US\">\u00a0<\/span><\/td>\n<\/tr>\n<tr>\n<td valign=\"top\" width=\"174\"><span lang=\"EN-US\">Launch configuration<\/span><\/td>\n<td valign=\"top\" width=\"449\"><span lang=\"EN-US\">A <i>launch configuration<\/i> is a template that an Auto Scaling group uses to launch EC2 instances. When you create a launch configuration, you specify information for the instances such as the ID of the Amazon Machine Image (AMI), the instance type, a key pair, one or more security groups, and a block device mapping.<\/span><span lang=\"EN-US\">\u00a0<\/span><\/td>\n<\/tr>\n<tr>\n<td valign=\"top\" width=\"174\"><span lang=\"EN-US\">Scaling plans<\/span><\/td>\n<td valign=\"top\" width=\"449\"><span lang=\"EN-US\">A\u00a0<i>scaling plan<\/i>\u00a0tells Auto Scaling when and how to scale. For example, you can base a scaling plan on the occurrence of specified conditions (dynamic scaling) or on a schedule.<\/span><span lang=\"EN-US\">\u00a0<\/span><\/td>\n<\/tr>\n<tr>\n<td valign=\"top\" width=\"174\"><span lang=\"EN-US\">Fleet management<\/span><\/td>\n<td valign=\"top\" width=\"449\"><i><span lang=\"EN-US\">Fleet management<\/span><\/i><span lang=\"EN-US\"> refers to the functionality that automatically replaces unhealthy instances and maintains your fleet at the desired capacity<\/span><span lang=\"EN-US\">\u00a0<\/span><\/td>\n<\/tr>\n<tr>\n<td valign=\"top\" width=\"174\"><span lang=\"EN-US\">Dynamic scaling<\/span><\/td>\n<td valign=\"top\" width=\"449\"><span lang=\"EN-US\">The <i>dynamic scaling<\/i> capabilities of Auto Scaling refers to the functionality that automatically increases or decreases capacity based on load or other metrics<\/span><span lang=\"EN-US\">\u00a0<\/span><\/td>\n<\/tr>\n<tr>\n<td valign=\"top\" width=\"174\"><span lang=\"EN-US\">Scaling policy<\/span><\/td>\n<td valign=\"top\" width=\"449\"><span lang=\"EN-US\">A <i>scaling policy<\/i> is a set of instructions for making such adjustments in response to an <i>Amazon CloudWatch<\/i> alarm that you assign to it. In each policy, you can choose to add or remove a specific number of instances or a percentage of the existing group size, or you can set the group to an exact size<\/span><span lang=\"EN-US\">\u00a0<\/span><\/td>\n<\/tr>\n<tr>\n<td valign=\"top\" width=\"174\"><span lang=\"EN-US\">Desired capacity<\/span><\/td>\n<td valign=\"top\" width=\"449\"><span lang=\"EN-US\">The number of EC2 instances that the group should have at any time, also called <i>desired capacity<\/i><\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p><span lang=\"EN-US\">\u00a0<\/span><\/p>\n<p><b><span lang=\"EN-US\">Summary<\/span><\/b><b><\/b><\/p>\n<ul type=\"disc\">\n<li><b><span lang=\"EN-US\">Don\u2019t MISS IT :\u00a0<\/span><\/b><a title=\"AWS Certified SysOps Administrator Associate \u2013 Practice Tests\" href=\"https:\/\/www.whizlabs.com\/aws-sysops-administrator-associate\/practice-tests\/\"><b><span lang=\"EN-US\">420 Practice Questions for SysOps Administrator\u00a0Exam (50% Discount)<\/span><\/b><\/a><\/li>\n<\/ul>\n<p><span lang=\"EN-US\">In this article, we have explained about how to maintain the availability and elasticity of EC2 instances using Auto Scaling service, the auto scaling lifecycle and distributing traffic between instances using load balancing.<\/span><\/p>\n<p><b><span lang=\"EN-US\">References:<\/span><\/b><\/p>\n<p><span lang=\"EN-US\">[1] Auto Scaling Faqs, <a href=\"https:\/\/aws.amazon.com\/autoscaling\/faqs\/\" target=\"_blank\" rel=\"noopener\">https:\/\/aws.amazon.com\/autoscaling\/faqs\/<\/a><br \/>\n[2] Amazon Auto Scaling Documentation,<\/span><a href=\"https:\/\/aws.amazon.com\/documentation\/autoscaling\/\" target=\"_blank\" rel=\"noopener\"><span lang=\"EN-US\">https:\/\/aws.amazon.com\/documentation\/autoscaling\/<\/span><\/a><span lang=\"EN-US\"><br \/>\n[3] AWS Certified SysOps Administrator \u2013 Associate Certification.<\/span><a href=\"https:\/\/aws.amazon.com\/certification\/certified-sysops-admin-associate\/\" target=\"_blank\" rel=\"noopener noreferrer\"><span lang=\"EN-US\">https:\/\/aws.amazon.com\/certification\/certified-sysops-admin-associate\/<\/span><\/a><\/p>\n","protected":false},"excerpt":{"rendered":"<p>Are you preparing for\u00a0AWS Certified SysOps Administrator \u2013 Associate certification exam? \u00a0Are you ready to pass this exam? In this blog, we are writing a series of articles on topics which are covered in the AWS certified SysOps associate certification exam. You can subscribe to us for receiving further updates on this topic. The SysOps Associate certification exam is the hardest exam in the associate level. We would recommend you pass both solution architect associated certification exam and developer associated certification exam first before of taking take this exam. The AWS Certified SysOps Administrator \u2013 Associate exam validates technical expertise [&hellip;]<\/p>\n","protected":false},"author":13,"featured_media":95761,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"_uag_custom_page_level_css":"","site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"default","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"default","adv-header-id-meta":"","stick-header-meta":"default","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"set","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center 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Gumaste","author_link":"https:\/\/www.whizlabs.com\/blog\/author\/pavan\/"},"uagb_comment_info":2,"uagb_excerpt":"Are you preparing for\u00a0AWS Certified SysOps Administrator \u2013 Associate certification exam? \u00a0Are you ready to pass this exam? In this blog, we are writing a series of articles on topics which are covered in the AWS certified SysOps associate certification exam. You can subscribe to us for receiving further updates on this topic. The SysOps&hellip;","_links":{"self":[{"href":"https:\/\/www.whizlabs.com\/blog\/wp-json\/wp\/v2\/posts\/23374","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.whizlabs.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.whizlabs.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.whizlabs.com\/blog\/wp-json\/wp\/v2\/users\/13"}],"replies":[{"embeddable":true,"href":"https:\/\/www.whizlabs.com\/blog\/wp-json\/wp\/v2\/comments?post=23374"}],"version-history":[{"count":6,"href":"https:\/\/www.whizlabs.com\/blog\/wp-json\/wp\/v2\/posts\/23374\/revisions"}],"predecessor-version":[{"id":95775,"href":"https:\/\/www.whizlabs.com\/blog\/wp-json\/wp\/v2\/posts\/23374\/revisions\/95775"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.whizlabs.com\/blog\/wp-json\/wp\/v2\/media\/95761"}],"wp:attachment":[{"href":"https:\/\/www.whizlabs.com\/blog\/wp-json\/wp\/v2\/media?parent=23374"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.whizlabs.com\/blog\/wp-json\/wp\/v2\/categories?post=23374"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.whizlabs.com\/blog\/wp-json\/wp\/v2\/tags?post=23374"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}