Registry
Understand registry
Service management is a core service registry, heartbeat mechanism dynamic maintenance
Service provider provider
Start their own network when reporting information to the registry
Consumers consumer service
Start their own network when reporting information to the registry, pulling provider of network-related information
Why use Registry
Micro-service machines and more and more, the caller needs to know the network address of the interface, if the configuration file on the way to control network addresses for dynamic new machines, great question.
Mainstream registry
zookeeper,Eureka,consul,etcd等
Distributed Application CAP theorem
cap Theorem
Refers in a distributed system, the consistency (Consistency), availability (Availability), fault tolerance partition (Partition tolerance), while three can be obtained
Consistency (C)
All backup data in distributed systems, and whether the same value at the same time. (Data from all nodes at the same time exactly the same, the more nodes, the more time-consuming data synchronization)
Availability (A)
After the load is too large, the entire cluster still be able to read and write in response to client requests. (Service has been available, and is the normal response time)
Fault tolerance partition (P)
Partition tolerance, that is, high availability, a node collapse, does not affect other nodes. (100 nodes, hang a few, does not affect the service, the more the better machine)
CAP theory
That is a distributed storage system, can only achieve the above two points. And because there will be a delay network hardware packet loss and other problems, so we have to partition fault tolerance is needed to achieve. So we can only make trade-offs between consistency and availability.