![]() Starting with SAP NetWeaver 7.52 you can use an updated version of the enqueue framework. It ensures that your workload continues operations as soon as possible even in case of underlying hardware failure. The service healing is enabled by default for all virtual machines running in all locations. If the failure happens on the physical host your workload will be redeployed to another server and data stored on permanent disks is preserved. If there is an issue with the power state, the virtual machine will be automatically restarted. When you deploy a virtual machine to Azure the hypervisor continuously monitors its status. ![]() So far it was a big limitation and basically enforced the usage of clustering. But as the lock table is stored in shared memory and there is no possibility to retrieve it over the network the Central Services instance has to be started on the same node as Enqueue Replication Service is running. Enqueue Replication Server keeps a replica of lock table in the shared memory of the passive node and in case of failover all lock entries can be retrieved and the consistency of the system is ensured even in case of Enqueue Server restart. ![]() To solve this challenge a highly available installation of Central Services instance includes an additional component that runs on the secondary node of the cluster. But whenever Enqueue Server is restarted the content of the lock table is lost and you can’t ensure the system consistency any longer. Temporary unavailability of a message server prevents new users from accessing the SAP system, but it won’t drop existing connections. Standalone Enqueue Server holds the user lock table.Message server is responsible for load balancing of user connections and communication between SAP instances.I’ll focus on two areas – Central Services instance and shared storage.īefore I present my solution, let’s have a closer look at the Central Services instance architecture. In today’s blog, I’ll try to answer if the above sample architecture could be simplified when running SAP in Azure. Quite often such complex architecture undermines your effort and, in the end, decreases the overall availability of your SAP system. Depending on the configuration you will also need a cluster witness that consists of several small Linux VMs. Firstly you need load balancers to route the user traffic to the correct node. A sample architecture includes three failover cluster to protect each system layer:įailover clusters require additional resources to work properly. As each component of the SAP system is a Single Point of Failure you need to ensure each of them is protected and accessible even in case of hardware failure. It requires failover clusters that are not easy to configure and maintain. I already covered the topic of high availability for SAP NetWeaver-based systems. Therefore many organizations decide to implement the system running in a highly available mode, which means all components of SAP system: database, central services instance and application servers are redundant, so even a hardware failure doesn’t stop the system. Even a small disruption could cause big challenges and lead to disruptions in business operations. It holds the most valuable data and many organizations fully relay on the availability of their SAP ERP or SAP S/4HANA solutions. ![]() When following the steps from the previous section, you reach step 5 and instead of typing "EN", as shown above, you type "THIO1" because you want to increase the trace level of the I/O thread 1 only.SAP is one of the most critical business systems deployed to the company landscape. They will be the I/O thread 0 (zero) and 1. ![]() Your standalone enqueue is configured with two I/O threads (parameter "enque/server/threadcount = 2"). THIO: I/O thread n (no specified: all I/O threads)ģ: Set/get trace status information on/from the enque serverĤ: Reload Enqueue Server ACL file (simple request)ħ: Get information about all enqueue server threadsĮxample: increasing the trace level of the I/O thread 1 only Area the action shall be limited to (default: EN): ![]()
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |