Module
CacheSync Module: contentXXL with several web servers
Summary
Function
Business content management with contentXXL provides a secure, available and scalable platform, which can also be operated with several Web servers, if needed.
Your benefit
high flexibility
high-performance
no additional software
Details "CacheSync - synchronization of different caches (e.g. for load balancing)"
Due to the effective page and data set caching in contentXXL, the high performance of the Microsoft .NET Framework and the extremely powerful database Microsoft SQL Server, contentXXL usually needs only one Web/application server adapted to the requirements even upon a great number of page views, in particular if the database is swapped to a second server. To further increase the scalability, security and availability, contentXXL can also be operated with several applications on one Web server or also with several Web servers, if required.
Several applications on one Web server
Due to the operation of several separate applications on one Web server, the security and availability of the application can be increased, if required. For example, one of the applications can be completely secured against external access by configuring appropriate IP addresses, ports or URLs. If desired and necessary, it can be ensured that the editor interface is not accessible externally via the Internet, in addition to the security of the login with access data. However, the same effect can be achieved more easily by using appropriately configured firewalls or programming measures.
The operation of different applications on one Web server requires much more resources. Furthermore, the caches of the various applications have to be synchronised. This task can be assumed by the CacheSync module.
Use of several Web servers
For reasons of scalability and in particular to ensure the availability, the use of several Web servers may be reasonable, e.g. in a cluster or load-balancing scenario. Various configurations are suitable for this purpose. The easiest way is the operation of several Web/application servers, each of them only containing the application logic (programme code). The data can be used together, e.g. via a database cluster as well as an accordingly fail-safe file share. This way, editors can also be provided with an extra Web server, which guarantees constant performance even at maximum load of the system due to visitor accesses.
As a matter of principle, both the database and the data in the data system can be replicated by means of the operating system, the database or tools of external service providers; however, the advantages and disadvantages of such a configuration should be carefully considered.
The caches of the applications on the various Web serves need to be synchronised in this case as well. This task can be assumed by the CacheSync module.
Synchronisation of the caches of the different applications and/or servers
The CacheSync module is configured via an XML file with the addresses of the concurrently operating applications and/or servers. In case of editorial changes, the application in which the change has been made notifies all other applications via the CacheSync module. The respective caches of the other applications are also disposed of after this notification. The required information is recompiled on the basis of the respective data sources and subsequently cached again locally.