What is the full form of HAC?

Introduction

High Availability Clusters (HAC) are nothing but a group of hosts which act as a single system and provide availability all the time.

It is one of the most major parts of running any website. One can use these clusters if they have to perform some critical applications like running an e-commerce website, handling some loaded databases, managing some transaction processing systems, etc.

Components of HAC

High Component Clusters, being one of the major parts of running a website, must have some components to make it work. They have three components: Primary HA Host, Secondary HA Host and IP address. A full detail about these three are mentioned below −

• Primary HA Host − The Primary HA Host is the host in your SIEM, IBM and QRadar deployment. Since facing a system failover is always a reality, this particular component always requires protection in case any failover happens. When an HA cluster is made, the primary HA host’s IP address gets reassigned to the existing IP address of the cluster. That is why creating an unused IP address and assigning it to the primary HA host is an absolute must.

• Secondary HA Host − Just like the Primary HA host acts as the standby system of the secondary host, the Secondary HA Host also works as a standby of the Primary HA host. So, its main purpose is to provide enough support when the Primary HA host fails. During the creation of the HA cluster, the Secondary HA host’s name gets changed and it becomes <cluster_host_name>-secondary, and just like the Primary HA host, its name too cannot be changed.

• Virtual IP Address − Virtual IP address is another main component of the High Availability Clusters. During the creation of an HA cluster, the primary HA host’s IP address is taken by the Virtual IP address.

• Load Balancing − High Availability Clusters should have a pre-engineered mechanism which is pre-designed to get help for load balancing. This load balancing can specify the failover process if a node fails to work.

• Diversity − When it comes to IT sectors, the availability of cloud technology is essential as it can distribute the clusters to various geographical locations. It ensures that the application can resist any disaster affecting any location.

• Scalable Data − Any High Availability Clusters must consider the data or disk storage units. Therefore using a centralized database is an option, which ensures that individual applications maintain the data

• Backup − Any High Availability Cluster is prone to various errors and breakdown. One of the most major breaks is slowdown of the process, which can bring down the whole service. If it happens, the system should have a plan to restore the data, which means having a recovery strategy.

Benefits of HAC

High Availability Clusters, being a group of hosts that works to complete high mission tasks, cannot be used by everyone. However, there are certain cases where the use of HAC is visible due to its various benefits. Here are some benefits of High Availability Clusters −

• Financial Institution Like Banks − Any financial institution like bank is one of the first places where the use of HAC is visible. Just imagine if a bank’s system gets shut for an entire day, or it becomes offline, what would happen? All the customers will start panicking thinking their money is not secure. As a result, they will switch to another institution. But having an High Availability Cluster’s web hosting makes the financial institution’s system secure and more robust.

• eCommerce Website − The usage of High Availability Clusters in eCommerce websites is very essential. Consider an eCommerce website which generates the maximum amount of traffic surges. If this kind of website faces a downtime for a few seconds, the popularity of the website starts getting a lot of questions. However, by using HAC, the eCommerce website can stay online and experience a spike in traffic.

• Rideshare − Any website providing ride sharing services also needs HAC to function properly. If the system of the website breaks down or the mobile application stops working, then riders cannot place their order and the driver cannot find the route. It can prove to be a big blow to the company. In addition, it will also lose revenue. To avoid this type of problem any ridesharing website needs High Availability Clusters.

Challenges in Implementing HAC

One of the biggest challenges faced while implementing HAC is the failover of one of the components. Even though there are standby systems as a backup, the failover is a big challenge. However, there are a few ways to configure a failover. Those are mentioned below −

• Fail Fast − Fail Fast, it is scripted as “FAIL-FAST”. It means that if curing the failure attempt fails, it is not possible to reach the first node.

• On Fail, Try All − It is scripted as “ON_FAIL_TRY_ALL_AVAILABLE”, which means the system is trying to cure the failover with all the existing and available nodes.

• OnFail, Try One − It is scripted as “ON_FAIL_TRY_ONE_NEXT_AVAILABLE”. It means that before giving up due to the failure, the system tries out at least one host.

Conclusion

High Availability Clusters or HAC, being a group of robust hosts, can provide unstoppable availability while being in one system. Even though it runs the chances of getting failed, its backup process and failure configuration methods can help the system to stay put. That is why it has become one of the most trustworthy groups of hosts for various websites.

FAQs

Q1. Does any small website need HAC?

Ans: No. Since HAC is a group of hosts that provides strong availability to the website while balancing a heavy load, it is not needed in any small website.

Q2. Can any financial institution get shut due to a little problem in the system?

Ans: No. A little problem in the system can make the customer feel that their money is not secure, but it cannot shut the institution.

Q3. Does a momentary shut down affect the revenue of a company?

Ans: Yes, a momentary shutdown affects the revenue of a company.