Resiliency - CompTIA Security+ SY0-701 - 3.4
High Availability and Resiliency in Information Security
Understanding High Availability (HA)
- In information security, maintaining system uptime and availability is crucial. High Availability (HA) is a strategy to ensure resiliency by using multiple components that can replace failed ones.
- HA configurations keep systems always on and available, allowing one system to take over if another fails, thus providing continuous service.
- While HA enhances availability, it incurs additional costs due to the need for more components and possibly upgraded power supplies.
Server Clustering
- Server clustering involves multiple servers working together as a single unit, presenting a unified server cluster to users while enhancing scalability.
- This setup allows real-time addition or removal of devices from the cluster, adjusting capacity as needed without user awareness of individual servers.
- Servers in a cluster typically run identical operating systems for interoperability and maintain synchronization through shared storage rather than local drives.
Load Balancing
- Load balancing distributes requests across multiple servers using a central load balancer, which does not require individual servers to be aware of each other.
- The load balancer manages device requests efficiently; it can add or remove servers dynamically based on network capacity needs or server failures.
- If a server fails, the load balancer automatically redistributes the load among remaining operational servers.
Site Resiliency
- Site resiliency involves having recovery sites ready for disaster scenarios where data is synchronized at an alternate location for continuity during outages.
- Organizations may switch operations to these recovery sites temporarily or for extended periods until normal operations can resume post-disaster.
Types of Recovery Sites
- A hot site is an exact replica of the primary data center with synchronized data and hardware ready for immediate use in case of failure.
- Cold sites are empty facilities requiring all necessary equipment and data to be brought in when needed; they have basic infrastructure like power but lack pre-installed resources.
Disaster Recovery and Resiliency Strategies
Importance of Geographical Dispersion in Recovery Sites
- Having a recovery site located far from the primary location reduces the risk of simultaneous impact from disasters like hurricanes or floods.
- A recovery site in a different state is less likely to be affected by the same storm, enhancing overall resilience.
- Considerations must include logistics for transporting equipment and personnel to the recovery site during natural disasters.
Platform Diversity as a Resiliency Strategy
- Operating systems have unique vulnerabilities; patching known issues is essential, but undiscovered vulnerabilities pose risks.
- Utilizing multiple operating systems (e.g., Linux, Windows, macOS) can mitigate risks associated with single OS vulnerabilities.
- This strategy helps spread risk across different platforms, potentially limiting exposure to any one vulnerability.
Cloud Provider Redundancy
- Employing multiple cloud providers (e.g., AWS, Microsoft Azure, Google Cloud) ensures that an outage with one does not affect others.
- Services can be distributed across various providers to maintain uptime and availability during outages or security concerns.
Continuity of Operations Planning (COOP)
- In scenarios where technology fails completely, nontechnical methods must be employed to continue operations effectively.