Differentiating between Hardware and Software Load Balancer

By CIOReview | Thursday, June 8, 2017

Load balancers, which were once dedicated only to the realm of hardware devices, can now be implemented effectively in software on another server. The thin line between hardware and software load balancers is diminishing rapidly. These load balancing tools can ensure maximum service availability by offering network traffic distribution services.

One of the major differences between a hardware and software load lies in the available capacity and the amount of labor invested in the platform. Understanding this difference is like winning half the battle for tech advisors, and deciding on the better approach is the other half. So how do you select the best among the hardware and software load-balancer? To choose the best load-balancer tools, enterprises must consider the one that offers more capacity, feature set, and support to the organizational needs in the data center.   

This article breaks down the differences and similarities between hardware and software load balancers.

Built with active application-specific integrated circuits, hardware load balancers assist in managing the data with minimum effect on a central processor.  On the other hand, in software-based load-balancing methodologies, a particular service runs on each machine in a cluster. These machines are further designated as a primary cluster server, which distributes load to the other servers in the cluster. This process helps in identifying the server that goes down. And the information is alerted through communication among each server's cluster service, and they act to absorb the extra load. The only barrier for this approach is the machine would need access to the Web servers to act as their clustering agents, which eliminates failure of the load balancer.

Hardware vs. Software

Hardware load balancers are dependent on firmware to provide the internal code base that operates the device. It leverages a management provision to update the firmware as new versions, patches, and bug fixes. Though, firmware updates are downloadable; the patch process often includes common operating system or application file patches. These load balancers also have the ability to update application security features such as firewalls, or some malware protection to secure systems from cyber threats. Software load balancers could be receptive to OS versions, and virtual appliance deployments could experience hypervisor dependencies. If enterprises can choose the software load balancing route, make sure that the updates do not adversely affect the software load balancer.

Furthermore, with the help of agents, load balancing hardware can notify various factors of the performance of the system, such as process utilization, CPU utilization, and other vital machine statistics. Based on this data, the device routes the request to the most available server.

Another drawback of hardware load balancer is the complex set-up process. Generally, hardware load balancer is dual-homed; deploying this requires fairly robust knowledge of TCP/IP networking principles. In addition to this, the ability to absorb new concepts associated with the load-balancing hardware is also a must.

For instance, one downside to load-balancing hardware is enough to break down the system. To consolidate this issue, most load-balancing hardware manufacturers recommend users to purchase two boxes and set them up so that the second can flawlessly take over for the first in case of failure. This backup box is known as a hot spare. Additionally, there is also need to address security and administration issues for load-balancing hardware, just as users would do for any other machine on their network.