High Availability Load Balancing: What Is It? | Parallels Insights!

What Is High Availability Load Balancing? 

high availability load balancingHigh availability load balancing (HALB) is an IT concept where a server fulfills a user’s request by utilizing failover mechanisms to reduce or eradicate the effects of any component failure. Organizations that support hundredsif not thousandsof users support these large volumes by pooling servers into groups, sometimes called farms. 

High availability load balancing and load balancers. 

A load balancer resides in front of the server group and balances the traffic to individual servers in a way that maximizes efficiency. With multiple servers grouped in a single unit, organizations can ensure that if a server goes down, the traffic is routed to the next available server. In this case, users don’t receive an error or failure of service. 

The load balancer is the key component in the IT infrastructure that ensures high availabilityAdvanced load balancers can even monitor the health of servers, deploy additional servers when traffic spikes and reboot servers that are experiencing issues. 

What kinds of high availability load balancing are there? 

There are two types of load balancers available for high availability load balancing: the software-based and the hardware-based. 

Hardware load balancers 

Hardware load balancers consist of physical hardware, such as an appliance. These direct traffic to servers based on criteria like the number of existing connections to a server, processor utilization, and server performance. These come with their firmware that requires maintenance and software updates 

Hardware load balancers offer better performance and control with a fuller range of featureslike Kerberos authentication and Secure Sockets Layer (SSL) hardware acceleration—but require some level of proficiency for management and maintenance. Due to being hardware-based, these load balancers are not very flexible and scalable, so there is a tendency to over-provision hardware load balancers. 

Software load balancers 

Software load balancers are more straightforward to deploy than hardware versions. They are also more cost-effective and flexible and used in conjunction with software development environments. The software approach provides you the flexibility of configuring the load balancer to your environment’s specific needs. Compared to hardware versions, which offer more of a closed-box approach, software balancers grant you more liberty when it comes to changes and upgrades. 

Software load balancers can come as prepackaged virtual machines (VMs) to spare you some of the configurations but may not offer all of the features available with hardware versions. 

Software load balancers are available as standalone solutions that require configuration and management or as a cloud service—known as Load Balancer as a Service (LBaaS). Choosing the cloud service frees you from the maintenance, management, and upgrading of the locally installed server. The cloud provider handles these tasks. 

How Parallels RAS helps with high availability load balancing 

Parallels® Remote Application Server (RAS) offers you a two-point load balancing to ensure high availability. The first point of contact is an external high availability load balancer (HALB) appliance, which is a standalone VM deployed in UNIX. This is responsible for load balancing the traffic between the gateways before the actual connection. 

The second point of contact is configurable from inside the Parallels RAS Console and is about the traffic after connecting through the gateways. There are two methods: round-robin and resource-based load balancing mechanisms. 

Both HALB points are included in the standard license and require minimum effort to set up. The integrated load balancing is automatically enabled by default. 

Download your 30-day evaluation period of Parallels RAS and experience the benefits of the high availability load balancing! 


IBM | https://www.ibm.com/cloud/learn/load-balancing 

NGINX | https://www.nginx.com/resources/glossary/load-balancing/ 

Digital Ocen | https://www.digitalocean.com/community/tutorials/what-is-high-availability 

Wikipedia | https://en.wikipedia.org/wiki/Load_balancing_(computing) 

HAProxy | https://www.haproxy.com/de/loesungen/high-availability/ 

Parallels | https://www.parallels.com/products/ras/capabilities/load-balancing/