1. Common Tomcat clustering solutions:
1) using ip hash policy nginx is to maintain an IP connection is always on one machine
Advantages: the prior art can not change the architecture implemented directly scale, easy. But the disadvantages are also obvious, actual production, rarely used in this way
Disadvantages: a) single server request (load) is not balanced, it is the case of dynamic changes completely dependent on ip hash result b) client ip, can not be served because of possible ip hash is different every time, you can not always remains connected only on the same machine
2) the use or memcache nosql redis such as database, server implement a cache of session, when the request came, all the tomcat server are unified to the server where the reading session information. This is more commonly used in business a solution.
2. nginx load balancing configuration, common strategies, scenarios and features
1) Polling (default)
Advantages: simple
Disadvantages: does not consider the processing capacity of each server
2) weight, more use of strategies
Pros: Consider different for each server processing power, high-performance machines which give the right to which machine weights higher
3）ip hash
Advantages: can always access the same server to achieve the same user
Cons: average is not necessarily based on ip hash
4) url hash (third-party plug-ins need to install plug-ins)
Advantages: able to access the same server to achieve the same service, which is carried out according to the load url
Cons: ip hash and the same, according to the average request is not necessarily url hash assignment, requesting frequent requests to the url on the same machine
5) fair (third-party plug-ins need to install plug-ins)
Preferentially allocated according to the response time of the backend server allocation request, the response time is short: Characteristics
3. Install deployment
https://blog.51cto.com/zero01/2112989