The Tech Lab by Aisha Ikram

Load Balancer A load balancer allows you to evenly distribute traffic to multiple servers in one or datacentre. If a datacentre or server becomes unavailable (unhealthy) the load balancer will route the traffic to only available datacentres with servers.  Load Balancer is very important infrastructure component which runs in front of every service to mange and route traffic load. Load balancer is used for scalable and available solutions. Running your workload across multiple Availability Zones ensures that if I or 2  AZs become unavailable your service / applications remains available.  load balancer behind the scene manages all the traffic across regions and scaled solutions  For more information about scalability and availability read here High Scalability  and the  High Availability 

 High Availability  Your ability for your service to remain available by ensuring there is  *no single point Of failure and/or ensure a certain level of performance. High availability is achieved by replicating the images in multiple zones or data centres. So in case of any geo-disaster the alternative systems serve the users, hence it is called highly available. There are three types of redundancies: Local Redundancy Zone Redundancy Global/Geo Redundancy Local redundancy The default behaviour is locally replicating the data/resource images in multiple copies in the same datacentre. The resources by default have three copies. so if one copy fail to serve the other two are still available. This mode has less availability comparing to the other two but still it provides some piece of mind. Zones Redundancy  In this mode three copies of the resources are kept in three different zones or data centres in the same location/city. For example, UK West is a location which may...