{"id":73293,"date":"2025-09-23T07:18:24","date_gmt":"2025-09-23T00:18:24","guid":{"rendered":"https:\/\/itsystems.vn\/high-availability-ha-25-09-23\/"},"modified":"2026-07-29T11:26:03","modified_gmt":"2026-07-29T04:26:03","slug":"high-availability-ha-25-09-23","status":"publish","type":"post","link":"https:\/\/itsystems.vn\/en\/high-availability-ha-25-09-23\/","title":{"rendered":"High Availability (HA): A Guide to Implementing Reliable Solutions 2024"},"content":{"rendered":"<p>In the digital age, service interruptions can cause significant financial and reputational losses. <a href=\"https:\/\/itsystems.vn\/en\/it-helpdesk-service\/\" title=\"Solution to help businesses maintain operations\">The High Availability (HA) solution<\/a> was developed to address this issue, ensuring that your system operates reliably and is ready for use. This article will provide a comprehensive overview of <strong>High Availability<\/strong>, from basic concepts and popular deployment models to detailed configuration guides, helping you build a robust and resilient (HA) system to meet all business needs.<\/p>\n<div id=\"ez-toc-container\" class=\"ez-toc-v2_0_86 counter-hierarchy ez-toc-counter ez-toc-light-blue ez-toc-container-direction\">\n<div class=\"ez-toc-title-container\">\n<p class=\"ez-toc-title\" style=\"cursor:inherit\">The content of the article<\/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: #999;color:#999\" 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: #999;color:#999\" 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:\/\/itsystems.vn\/en\/high-availability-ha-25-09-23\/#What_is_High_Availability_HA_Why_is_it_important_for_businesses\" >What is High Availability (HA)? Why is it important for businesses?<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-2\" href=\"https:\/\/itsystems.vn\/en\/high-availability-ha-25-09-23\/#A_detailed_easy-to-understand_definition_of_HA\" >A detailed, easy-to-understand definition of HA<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-3\" href=\"https:\/\/itsystems.vn\/en\/high-availability-ha-25-09-23\/#The_importance_of_HA_in_ensuring_service_continuity\" >The importance of HA in ensuring service continuity<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-4\" href=\"https:\/\/itsystems.vn\/en\/high-availability-ha-25-09-23\/#Real-world_examples_of_the_impact_of_a_system_without_HA\" >Real-world examples of the impact of a system without HA<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-5\" href=\"https:\/\/itsystems.vn\/en\/high-availability-ha-25-09-23\/#Distinguishing_between_High_Availability_HA_and_Disaster_Recovery_DR\" >Distinguishing between High Availability (HA) and Disaster Recovery (DR)<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-6\" href=\"https:\/\/itsystems.vn\/en\/high-availability-ha-25-09-23\/#Common_High_Availability_deployment_models\" >Common High Availability deployment models<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-7\" href=\"https:\/\/itsystems.vn\/en\/high-availability-ha-25-09-23\/#1_Active-Active_Model\" >1. Active-Active Model<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-8\" href=\"https:\/\/itsystems.vn\/en\/high-availability-ha-25-09-23\/#Advantages_and_disadvantages_of_the_Active-Active_model\" >Advantages and disadvantages of the Active-Active model<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-9\" href=\"https:\/\/itsystems.vn\/en\/high-availability-ha-25-09-23\/#Example_of_Active-Active_model\" >Example of Active-Active model<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-10\" href=\"https:\/\/itsystems.vn\/en\/high-availability-ha-25-09-23\/#2_Active-Passive_Model\" >2. Active-Passive Model<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-11\" href=\"https:\/\/itsystems.vn\/en\/high-availability-ha-25-09-23\/#Example_of_Active-Passive_model\" >Example of Active-Passive model<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-12\" href=\"https:\/\/itsystems.vn\/en\/high-availability-ha-25-09-23\/#Comparing_and_choosing_a_HA_model_that_fits_actual_needs\" >Comparing and choosing a HA model that fits actual needs<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-13\" href=\"https:\/\/itsystems.vn\/en\/high-availability-ha-25-09-23\/#Architectural_components_of_a_High_Availability_system\" >Architectural components of a High Availability system<\/a><ul class='ez-toc-list-level-3' ><li class='ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-14\" href=\"https:\/\/itsystems.vn\/en\/high-availability-ha-25-09-23\/#Load_Balancer_The_systems_Related_services_from_IT_Systems_If_your_team_is_dealing_with_this_issue_in_a_live_business_environment_these_services_can_help_you_move_from_diagnosis_to_a_stable_operating_process_Windows_licensing_for_business_Windows_license_pricing_IT_support_services_FAQ_When_should_a_business_ask_IT_Systems_for_support\" >Load Balancer: The system&#8217;s \n\n\nRelated services from IT Systems\nIf your team is dealing with this issue in a live business environment, these services can help you move from diagnosis to a stable operating process.\n\nWindows licensing for business\nWindows license pricing\nIT support services\n\n\n\n\nFAQ\nWhen should a business ask IT Systems for support?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-15\" href=\"https:\/\/itsystems.vn\/en\/high-availability-ha-25-09-23\/#Can_IT_Systems_help_review_the_current_environment_before_proposing_a_solution\" >Can IT Systems help review the current environment before proposing a solution?<\/a><\/li><li class='ez-toc-page-1 ez-toc-heading-level-3'><a class=\"ez-toc-link ez-toc-heading-16\" href=\"https:\/\/itsystems.vn\/en\/high-availability-ha-25-09-23\/#Does_this_topic_connect_to_ongoing_IT_operations\" >Does this topic connect to ongoing IT operations?<\/a><\/li><\/ul><\/li><li class='ez-toc-page-1 ez-toc-heading-level-2'><a class=\"ez-toc-link ez-toc-heading-17\" href=\"https:\/\/itsystems.vn\/en\/high-availability-ha-25-09-23\/#Need_help_applying_this_to_your_business\" >Need help applying this to your business?<\/a><\/li><\/ul><\/nav><\/div>\n<h2><span class=\"ez-toc-section\" id=\"What_is_High_Availability_HA_Why_is_it_important_for_businesses\"><\/span>What is High Availability (HA)? Why is it important for businesses?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p><strong>High Availability (HA)<\/strong> is an important concept in IT service management, especially for large enterprises operating in a fiercely competitive environment. It not only ensures that services, applications, and systems are always available for users but also contributes to maintaining the reputation and profitability of the business.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"A_detailed_easy-to-understand_definition_of_HA\"><\/span>A detailed, easy-to-understand definition of HA<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>High Availability (HA) can be defined as the ability of a system to provide continuous service over a period of time. To achieve this, the system must have appropriate solutions and configurations to automatically switch between components in case one component fails.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"The_importance_of_HA_in_ensuring_service_continuity\"><\/span>The importance of HA in ensuring service continuity<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>In today&#8217;s digital world, any disruption can lead to significant financial and reputational damage. Implementing <strong>High Availability<\/strong> not only minimizes downtime but also protects data and ensures that services are always available for customers. For example, a major website going down during peak hours can lose millions of dollars in revenue.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Real-world_examples_of_the_impact_of_a_system_without_HA\"><\/span>Real-world examples of the impact of a system without HA<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Large enterprises like Amazon and Google always prioritize HA implementation to ensure their services are uninterrupted. A failure in the signal from one server can lead to the entire system losing information, immediately affecting millions of users at once.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Distinguishing_between_High_Availability_HA_and_Disaster_Recovery_DR\"><\/span>Distinguishing between High Availability (HA) and Disaster Recovery (DR)<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Although both HA and DR are related to service continuity, their goals, scope, and approaches are entirely different. HA focuses on maintaining continuous service operation, while DR emphasizes recovering services after a major incident. While both can be combined into one strategy, each business needs to clarify its priorities.<\/p>\n<h2><span class=\"ez-toc-section\" id=\"Common_High_Availability_deployment_models\"><\/span>Common High Availability deployment models<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<h3><span class=\"ez-toc-section\" id=\"1_Active-Active_Model\"><\/span>1. Active-Active Model<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>The <strong>Active-Active<\/strong> model uses multiple servers working simultaneously, optimizing resources and increasing load capacity. In this model, all servers can handle user requests, reducing the load on each server and improving response speed.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Advantages_and_disadvantages_of_the_Active-Active_model\"><\/span>Advantages and disadvantages of the Active-Active model<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>The advantage of Active-Active is the ability to maximize resource utilization and ensure even load distribution. However, a significant disadvantage is the complexity in management and the need for continuous data synchronization between servers.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Example_of_Active-Active_model\"><\/span>Example of Active-Active model<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>For instance, a web application with multiple servers serving users, a <strong>load balancer<\/strong> will coordinate traffic between these servers.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"2_Active-Passive_Model\"><\/span>2. Active-Passive Model<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>The <strong>Active-Passive<\/strong> model, also known as Standby, only has one active server (Active), while the standby server (Passive) does not operate until the Active server fails. The advantage of this model is its simplicity in management and low cost, but it leads to resource wastage since the passive server is not utilized.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Example_of_Active-Passive_model\"><\/span>Example of Active-Passive model<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>A typical example is the primary database server and the backup database server. When the primary server fails, the backup server will automatically activate to continue providing services to users.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Comparing_and_choosing_a_HA_model_that_fits_actual_needs\"><\/span>Comparing and choosing a HA model that fits actual needs<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<table>\n<tr>\n<th>Factor<\/th>\n<th>Active-Active<\/th>\n<th>Active-Passive<\/th>\n<\/tr>\n<tr>\n<td>Cost<\/td>\n<td>High<\/td>\n<td>Low<\/td>\n<\/tr>\n<tr>\n<td>Complexity<\/td>\n<td>High<\/td>\n<td>Low<\/td>\n<\/tr>\n<tr>\n<td>Failover time<\/td>\n<td>Fast<\/td>\n<td>Slow<\/td>\n<\/tr>\n<tr>\n<td>Load capacity<\/td>\n<td>High<\/td>\n<td>Medium<\/td>\n<\/tr>\n<\/table>\n<p>Questions to ask when determining the appropriate model include:<\/p>\n<ul>\n<li>How important is minimizing downtime?<\/li>\n<li>What is the budget for implementing and maintaining HA systems?<\/li>\n<li>What level of complexity can the technical team manage?<\/li>\n<\/ul>\n<h2><span class=\"ez-toc-section\" id=\"Architectural_components_of_a_High_Availability_system\"><\/span>Architectural components of a High Availability system<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<h3>Load Balancer: The system&#8217;s<br \/>\n<!-- its-deep-aio-en-related-2026-07-27 --><\/p>\n<section class=\"its-deep-aio-related\" aria-label=\"Related IT Systems services\">\n<h2>Related services from IT Systems<\/h2>\n<p>If your team is dealing with this issue in a live business environment, these services can help you move from diagnosis to a stable operating process.<\/p>\n<ul>\n<li><a href=\"https:\/\/itsystems.vn\/en\/microsoft-business-licensing\/microsoft-windows-licensing\/\">Windows licensing for business<\/a><\/li>\n<li><a href=\"https:\/\/itsystems.vn\/en\/microsoft-business-licensing\/windows-license-pricing\/\">Windows license pricing<\/a><\/li>\n<li><a href=\"https:\/\/itsystems.vn\/en\/it-services-for-businesses\/it-support-services\/\">IT support services<\/a><\/li>\n<\/ul>\n<\/section>\n<p><!-- its-deep-aio-en-faq-2026-07-27 --><\/p>\n<section class=\"its-deep-aio-faq\" aria-label=\"Frequently asked questions\">\n<h2>FAQ<\/h2>\n<h3>When should a business ask IT Systems for support?<\/h3>\n<p>Ask for support when the issue affects users, business data, security, licensing compliance, service availability or daily operations. A short technical review often prevents repeated incidents and hidden costs.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Can_IT_Systems_help_review_the_current_environment_before_proposing_a_solution\"><\/span>Can IT Systems help review the current environment before proposing a solution?<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>Yes. IT Systems can review the current setup, identify risks, map the issue to the right service scope and recommend a practical next step for your business.<\/p>\n<h3><span class=\"ez-toc-section\" id=\"Does_this_topic_connect_to_ongoing_IT_operations\"><\/span>Does this topic connect to ongoing IT operations?<span class=\"ez-toc-section-end\"><\/span><\/h3>\n<p>In most cases, yes. Problems around software, cloud, endpoint, network, backup or security should be connected to a broader IT operations plan instead of being handled as isolated incidents.<\/p>\n<\/section>\n<p><!-- its-deep-aio-en-cta-2026-07-27 --><\/p>\n<section class=\"its-deep-aio-cta\" aria-label=\"Contact IT Systems\">\n<h2><span class=\"ez-toc-section\" id=\"Need_help_applying_this_to_your_business\"><\/span>Need help applying this to your business?<span class=\"ez-toc-section-end\"><\/span><\/h2>\n<p>IT Systems Vietnam can help assess the issue, recommend the right service path and support implementation for your team.<\/p>\n<p><a class=\"button\" href=\"https:\/\/itsystems.vn\/en\/contact-it-systems-vietnam\/\">Contact IT Systems<\/a> <a class=\"button\" href=\"https:\/\/itsystems.vn\/en\/it-services-for-businesses\/it-support-services\/\">View IT support services<\/a><\/p>\n<\/section>\n","protected":false},"excerpt":{"rendered":"<p>In the digital age, service interruptions can cause significant financial and reputational losses. The High Availability (HA) solution was developed to address this issue, ensuring that your system operates reliably and is ready for use. This article will provide a comprehensive overview of High Availability, from basic concepts and popular deployment models to detailed configuration [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":73291,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"rank_math_focus_keyword":"High Availability (HA)","rank_math_title":"High Availability (HA): A Guide to Implementing Reliable Solutions 2024","rank_math_description":"High Availability (HA) ensures that systems are always available, minimizing downtime for businesses.","rank_math_robots":"","rank_math_canonical_url":"","rank_math_schema":"","footnotes":""},"categories":[1344,2143],"tags":[],"class_list":["post-73293","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-uncategorized-en","category-it-service"],"wpml_current_locale":"en_US","wpml_translations":{"vi_VN":{"locale":"vi_VN","id":73290,"slug":"high-availability-ha-25-09-23","post_title":"High Availability (HA): H\u01b0\u1edbng d\u1eabn tri\u1ec3n khai gi\u1ea3i ph\u00e1p \u0111\u00e1ng tin c\u1eady 2024","href":"https:\/\/itsystems.vn\/high-availability-ha-25-09-23\/"}},"_links":{"self":[{"href":"https:\/\/itsystems.vn\/en\/wp-json\/wp\/v2\/posts\/73293","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/itsystems.vn\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/itsystems.vn\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/itsystems.vn\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/itsystems.vn\/en\/wp-json\/wp\/v2\/comments?post=73293"}],"version-history":[{"count":2,"href":"https:\/\/itsystems.vn\/en\/wp-json\/wp\/v2\/posts\/73293\/revisions"}],"predecessor-version":[{"id":85878,"href":"https:\/\/itsystems.vn\/en\/wp-json\/wp\/v2\/posts\/73293\/revisions\/85878"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/itsystems.vn\/en\/wp-json\/wp\/v2\/media\/73291"}],"wp:attachment":[{"href":"https:\/\/itsystems.vn\/en\/wp-json\/wp\/v2\/media?parent=73293"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/itsystems.vn\/en\/wp-json\/wp\/v2\/categories?post=73293"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/itsystems.vn\/en\/wp-json\/wp\/v2\/tags?post=73293"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}