How do you handle sessions in load balancer?
This is where the concept of “Sticky Sessions” or “Session Affinity” comes into play. You can configure many load balancers to route user sessions to the same machine. Another approach would be to maintain session information in a datastore accessible by both machines behind the load balancer.
How load balancing is done on a server?
Load balancing is defined as the methodical and efficient distribution of network or application traffic across multiple servers in a server farm. Each load balancer sits between client devices and backend servers, receiving and then distributing incoming requests to any available server capable of fulfilling them.
What is session based load balancing?
Session stickiness, a.k.a., session persistence, is a process in which a load balancer creates an affinity between a client and a specific network server for the duration of a session, (i.e., the time a specific IP spends on a website).
What are load balancing services?
Load balancing is a general term for various distribution techniques that help spread traffic and workload across different servers within a network. Put in human terms, the idea is simple: the more available hands working, the faster and more efficiently the job gets done, and the less work each person has to do.
What is session persistence session?
Session Persistence (sometimes called sticky sessions) involves directing a user’s requests to one application or backend web server for the duration of a “session.” The session is the time it takes a user to complete a transaction or task that might include multiple requests.
What are the types of load balancing?
Load Balancing Techniques:
- Round Robin. Round-robin load balancing is one of the simplest and most used load balancing algorithms.
- Weighted Round Robin.
- Least Connection.
- Weighted Least Connection.
- Resource Based (Adaptive)
- Resource Based (SDN Adaptive)
- Fixed Weighting.
- Weighted Response Time.
How do you implement load balancing?
Edit: Load balancing can be implemented by DNS round robin too. Each DNS lookup call returns another IP address for the same domain name. The client choose an IP and connects to this server. Another client can use the next IP.
Why is load balancing important?
The main purpose of load balancing is to prevent any single server from getting overloaded and possibly breaking down. In other words, load balancing improves service availability and helps prevent downtimes.
Where are the sessions stored in load balancing?
The solution is to go for storing the sessions in a SQL Server which is accessible across all the Web Servers of the Load Balancing environment. Instead of a theoretical discussion on this, let’s directly jump into some practical discussion by developing a small program that uses sessions and see how sessions work in Azure.
What is the purpose of network load balancing?
NLB is useful for ensuring that stateless applications, such as web servers running Internet Information Services (IIS), are available with minimal downtime, and that they are scalable (by adding additional servers as the load increases).
How does load balancing work for multiple hosts?
If you use the same set of load-balanced servers for multiple applications or websites, port rules are based on the destination virtual IP address (using virtual clusters). Direct all client requests to a single host by using optional, single-host rules. NLB routes client requests to a particular host that is running specific applications.
Why are sticky sessions used in load balancing?
To use Sticky Sessions we configure the load balancer to send the request for a specific session to the server that has served the first request. This can create a problem in the Load Balanced environment because it may be possible with Sticky Sessions that some of the servers are fully loaded and some are actually free at that time.