Currently the Java platform is one of the most consolidated in the world, much of this is due to platform's ability to support other languages such as Kotlin, Groovy and Scala, etc. Thousands of web and mobile applications are developed using the platform as a base. The Java platform has changed a lot in recent years and probably will keep evolving.
In parallel with these changes, we see the evolution application servers, that increasingly offer highly complex features such as load balancing components, smart asynchronous messaging, transaction control and many other technologies facilitating application development and standardization. They also provide a stable and scalable infrastructure for mission critical applications. One of the biggest challenges for application servers is to couple highly complex services, making them stable and flexible.
Ensuring SQL Server High Availability in the Cloud
Theoretically, the cloud seems tailor-made for ensuring high availability (HA) and disaster recovery (DR) solutions in mission critical SQL Server deployments. Azure, AWS, and Google have distributed, state-of-the-art data centers throughout the world. They offer a variety of SLAs that can guarantee virtual machine (VM) availability levels of 99.95% and higher.
But deploying SQL Server for HA or DR has always posed a challenge that goes beyond geographic dispersion of data centers and deep levels of hardware redundancy. Configuring your SQL Server for HA or DR involves building a Windows Server Failover Cluster (WSFC) that ensures not only the availability of different machines running SQL Server itself but also — and most importantly — the availability of storage holding the data in which SQL Server is interacting.
RocketMQ: HA Implementation
Introduction
When we talk about HA, normally people think about the failover mechanism. However, making the cluster available to messages is also considered HA. And to a certain extent, I think it is more important than just making the brokers available. After all, users can and will feel the impact of this availability.
Code Snippets
Here is the scenario: