Load balancing and failover both are different methods. In load balancing, all the requests distribute across multiple servers. Failover Protection redirects all the requests to another server if the parent server cannot accept the requests.
What is Load Balancing?
Load balancing is a method to distribute the network or application traffic to multiple servers. It lies between your servers and the user who is sending the request to the same server.
It receives the incoming requests and distributes them among the server, healthy inside the server farm.
Load balancing can be a hardware tool or software application. For hardware load balancing, you need to install a dedicated load-balancing device. A software load balancer can run on a virtual server or the cloud.
What are the methods for Load balancer configuration?
Here, we have mentioned a few methods for Load Balancing.
Round Robin:
In the Round Robin method, your traffic distributes on the rotation system. Load balancer passes the request based on the receiving order. Suppose there are three node servers in a cluster named server1, server2, and Server3. In this case, the first request will go to Server1, the second will go to server2, and the third will go to server3.
Weighted Round-Robin
It is similar to the round-robin method, but servers will receive the numerical weightage. With a higher numerical value will receive more requests.
Least Connections:
In the least connection method, traffic directs to the server with the least number of active connections. It helps while high traffic and allows you to maintain the traffic distribution to your servers.
Least Response Time:
In this method, the load balancer directs traffic to the server with the lowest average response time.
Least Bandwidth:
The application load balancer method calculates the traffic in Mbps. In this method, load balancers will send requests to the server with the lowest Mbps of traffic.
How Does the Load Balancing Work?
Here, we have mentioned the workflow of how load balancing works.
(1) Your Website Gets the Incoming Traffic Requests
A Website receives lots of concurrent requests from web visitors over the internet.
(2) All the Requests Distribute to Your Server Farm
A load balancer intercepts all the requests and redirects them to the available and healthy servers.
(3) Severs Inside Server Farm Operates with the Reasonable Workload
The server that is healthy and able to receive the request will accept the request and respond to the load balancer.
(4) The User Receives the Response to Their Request from the Node Server
Finally, the process completes as your website visitors receive to respond to their requests.
What is FailOver Protection?
Failover means switching to the standby or secondary server in case the primary server fails to respond. There will be a seamless failover, so your user wouldn’t be able to notice any server/hardware failure. Switching in the failover will be automatic without requiring human intervention.
It requires a minimum of two servers to achieve the failover. Failover can work with your Web, Database, or DNS servers. Using failover protection, we can make our system more fault-tolerant.
Two or more than two servers with a failover service and provide high availability (HA) called a Failover cluster. Providing the high-availability for your web application is the main aim of failover protection.
What is Active-active FailOver Protection?
In the active-active cluster, all the request distributes across all the nodes. It prevents a single node from overload and achieves load balancing. You need to ensure that all the settings on the node servers should be identical.
What is Active-passive FailOver Protection?
Just like the active-active cluster, an active-passive must have at least two nodes. However, not all of them are active. If there is a two-node system, the first node remains active, and the second node will remain passive. You can also call it a standby server of the failover cluster. Passive in a sense, it doesn’t remain in stopped status. The server will remain on and also require the same setting that you have on an active node. In case of an active server overloaded or unavailable to the server the request, the passive server will be in action and become active.
How does the fail-over protection work?
Here, we have mentioned the workflow of how load balancing works.
(1) Your Load-Balancer/Primary Node Server Receives Requests from the Internet
An end-users send the requests to your node server from the internet. This request could be for your application, DNS, Web, or related database.
(2) The Primary Node Server is Unavailable or Fails to Serve the Request
After the users send the request to your server, the primary server is unavailable due to the hardware failover or other disasters.
(3) The Secondary Node Server will Serve the Request in case the Primary Server Fails.
Because of the failover implementation, the secondary server will become active and respond to the user requests.
(4) Users will Get the Responses to Their Requests from the Secondary Server.
Finally, the user will receive the response from the secondary server.
