Hi, I read the following in TinyURL chapter -
We can add a Load balancing layer at three places in our system:
- Between Clients and Application servers
- Between Application Servers and database servers
- Between Application Servers and Cache servers
I’m not clear on point number 2 (Load balancer between App Server and DB server). If we have multiple DB servers say DB1, DB2, DB3. Then how is data in DB1 different from DB2 and DB3? Do they all contain same data? If yes, then how do we synchronize the data between DB1, DB2, DB3 when a new URL is inserted into DB1? How are changes propagated to other databases DB2 and DB3?
This is my first question here. So let me know if the posted in the wrong place.
Thanks