The Gold architecture for MAA is used to emphasis the application continuity. All the possible outages (planned or no) are protected by Oracle features. Here we are one step further and start to design using multi-site architecture. Data Guard, RAC, Oracle Clusterware, everything is there. But even with these, ZDLRA is still needed to allow complete protection.
With the MAA references, we have the blueprints and highlights how to protect them since the standalone/single instance until the multiple site database. But for Gold we are beyond RPO and RTO, they are important but application continuity and data continuity join to complete the whole picture.
The MAA defined Silver architecture for database environments that use (or need) high availability to survive for outages. The idea is having more than one single instance running, and to do that, it relies on Oracle Clusterware and Engineered Systems to mitigate the single point of failure. But is not just a database that gains with this, the Silver architecture is the first step to have application continuity. And again, ZDLRA is there since the beginning.
As you can see above, the Silver by MAA blueprints improves compared with Bronze architecture that I spoke at the last post. But the basic points are there: RPO and RTO. They continue to base rule here. And the goals are the same: Data Availability, Data Protection, Performance (no impact), Cost (lower cost), and Risk (reduce). More technical details here at the MAA Overview doc.
Oracle Maximum Availability Architecture (MAA) means more than just Data Guard or Golden Gate to survive outages, is related to data protection, data availability, and application continuity. MAA defines four reference architectures that can be used to guide during the deploy/design of your environment, and ZDLRA is there for all architectures.
With the MAA references, we have the blueprints and highlights how to protect them since the standalone/single instance until the multiple site database. The MAA goal is to survive an outage but also sustain: Data Availability, Data Protection, Performance (no impact), Cost (lower cost), and Risk (reduce).
The Oracle Maximum Availability Architecture (MAA) is the correct way to protect your Oracle database environment (and investment). It covers from a simple single instance to Exadata/Engineered Systems RACand a multi-site database with Data Guard protection. But do you know that to reach the MAA (whatever the architecture level that you are protecting) you need to use ZDLRA?
The question is why ZDLRA is needed? The point from ZDLRA is that it can (and needed to be used) to protect and reach zero RPO to all architectures. ZDLRA is more (much more) than just a backup appliance, is the core of every MAA design. You can’t reach zero RPO without using it.
The Virtual Private Catalog (VPC) user is a key piece for a good ZDLRA architecture design. The detail is not how to create it, but how to correctly integrate it in your design, and this is more important if you have replicated ZDLRA or using Real-Time redo transport.
Here I will show and discuss VPC implications for your architecture design when deploying ZDLRA. Even for a complete and new implementation (together with database) or adding ZDLRA at your already running environment. All points here try to show some perspectives and key points that can help you to correct use and define VPC’s.
Real-time redo transport is the feature that allows you to reduce to zero the RPO (Recovery Point Objective) for your database. Check how to configure real-time redo, the steps, parameters, and other details that need to be modified to enable it.
The idea behind real-time redo transport it is easy, basically the ZDLRA it is a remote destination for your redo log buffers/archivelogs of your database. It is really, really, similar to what occurs for data guard configurations (but here you don’t need to set all datafiles as an example). It is not the same too because ZDLRA can detect if the database stops/crash and will generate the archivelog (at ZDLRA side) with all the received redo and this can be used to restore to, at least zero/sub-seconds, of data loss.
This post starts from one environment that you already enrolled in the database at ZDLRA. I already wrote about how to do that, you can check here in my previous post. This is the first post about real-time redo, here you will see how to configure and verify it is working.
Recently I made a post about a little issue that I got with Oracle Data Guard. In that scenario, because of outage in the standby datacenter, healthy primary database shutdown with error “ORA-16830: primary isolated…”. Just to remember that the database was running with Maximum Availability, Fail-Start Failover enabled, and (the most important detail) the Observer was running in the standby datacenter too.
The point from my previous post tried to show that does not exists one doc that provides full details about “pros” and “cons” where put your observer. Whatever the place, on the primary datacenter or in standby, it has little details to check. Even the best (ideal) scenario, with a third datacenter, can be tough to sustain.
Here I will try to show one option that can help you and improve the reliability of your MAA/DG environment. At least, you will have more options to decide how to protect your database. Bellow, I show some details about how to configure and use multiple observers, but if you want to jump and see a little concern you can directly to the end of the post.