How can you design a disaster-recovery architecture for IT systems?

Designing a disaster recovery (DR) architecture for IT systems involves careful planning, consideration of various factors, and implementation of strategies to ensure business continuity in the event of a disaster. 1) Risk Assessment and Business Impact Analysis 2) Define Recovery Objectives: RTO and RPO 3) Implement the regular backups of critical data and systems and consider using both onsite and offsite backups for redundancy. 4) Redundant Infrastructure 5) Disaster Recovery site 6) Testing and Maintenance 7) Automation and Orchestration 8) Communication and Notification 9) Documentation and training

The first step in designing a disaster-recovery architecture is to identify your critical systems and data. These are the systems and data that are essential for your business operations and cannot afford to be lost or unavailable for an extended period. The next step is to define your recovery objectives. These are the metrics that you use to measure the success of your disaster-recovery efforts. Choose your recovery strategies: There are several recovery strategies that you can use to recover your IT systems and data after a disaster. Once you have designed your disaster-recovery architecture, you need to test it regularly to ensure that it works as intended.

RPO and RTO are the primary factors which should guide your recovery objectives. These are in turn effected both by business goals as well as compliance issues. You need to understand the requirement of laws and regulations associated with your business to arrive at a suitable RPO and RTO number. For example if you are into medical care then you cant afford to loose patient data and also that data should be accessible 24 x 7 whereas if you are into warehousing you may have slightly higher RPO and RTO. you also need to understand that having a lower RPO and RTO has a direct implication on cost of the DR and hence a deliberate and diligent discussion is required before decision making.

Vejo muitas empresas que possuem uma infra de DR, mas que na prática é falha, serve apenas para responder itens de compliance. Antes de se preocupar com a parte técnica, com os RxO's, com as tecnologias de replica??o, com a orquestra??o, eu acredito que é fundamental ter um BIA (Business Impact Analysis). é através dele que você vai descobrir o que realmente é afetado em seus negócios caso ocorra um desastre. Aí, de posse desse "documento" você vai definir quais sistemas devem ser alvo do seu projeto de DR, o que é razoável para que seu negócio seja zero ou minimamente afetado, qual a infra certa para recupera??o de desastre... Se come?ar pela infra, sem saber o que é importante recuperar, fica aquela coisa mais encenada que real.

In my opinion if the DR is at same location, its not classically a DR because both your primary and DR infra will get damaged in same fire/flood/earthquake etc. Hence its always better to have a DR location at least 200 miles apart from your primary location. IF finances are a constraint and your org cant afford another building, lease lines etc then also at least dont have DR on same rack/same room etc. Avoid too much of proximity when selecting DR site.

One very important thing which I wish to mention here is that the importance of security at the DR location. What i have personally seen is that the DR site may have same infra and other associated things when talking of operational aspects but many a times the level of security at DR site is not that of like the main site. This poses a great threat to security of infra as well as data. So pls have the same level of security both physical as well as logical including access control mechanisms for premises and devices.