In computing, load balancing improves the distribution of workloads across multiple computing resources.
The need for this software solution appears large web development technologies as well as the number of internet users.
There is a diagram that shows the increase of internet users in the last twenty years.

With this increase internet users there has been an increasing need for hardware power.
Software engineers have developed several software to speed up the flow of information and response of servers.
On of these is Load Balancing. Load balancing works by listening to all servers which have been networked in load balancing network.
During listening load balancing has access into load of server and on the basis of the information specifies which server execute the current required action.
This was a brief introduction to what is load balancing, with what I as a developer had a problem is what if the server while doing load balancing execute some applications switch to another server.
In this case everything that is created on the previous server will not be available to the next.
In this particular case if you create a folder to store data as for example pictures.
And during use applications do upload the image, this image will be seen more in the application if load balancing switch carry out the less loaded server.
To avoid this case, you have to create virtual directory(shared folders). These folders knows every server that is networked to load balancing infrastructure,
or any server in the network has access to these folders
