A. Active/active controller architecture
B. Stateful controller architecture
C. Active/passive controller front-ends ports
D. Primary/secondary controller architecture
Explanation:
During a controller upgrade of a Pure Storage FlashArray, the active/active controller architecture ensures there will be no tangible impact on performance. This design allows both controllers to handle I/O operations simultaneously, so even if one controller is being upgraded, the other can continue processing workloads without interruption.
Why This Matters:
Active/Active Architecture: In an active/active design, both controllers share the workload equally. If one controller is taken offline for maintenance or upgrades, the remaining controller seamlessly handles all I/O operations.
This ensures continuous availability and consistent performance during upgrades, minimizing downtime and user impact.
Why Not the Other Options?
B. Stateful controller architecture:
While stateful architectures maintain session information, they do not inherently ensure no performance impact during upgrades. The key factor here is the active/active design.
C. Active/passive controller front-end ports:
In an active/passive design, only one controller is actively handling I/O at any given time. If the active controller is upgraded, the passive controller must take over, which can lead to temporary performance degradation.
D. Primary/secondary controller architecture:
Similar to active/passive, this design relies on a primary controller for all operations, making it less resilient during upgrades compared to active/active.
Key Points:
Active/Active Design: Ensures continuous I/O processing during upgrades.
Seamless Upgrades: Minimizes performance impact and downtime for users.
High Availability: Maintains consistent performance and reliability throughout the upgrade process.
Reference: Pure Storage FlashArray Documentation: "Controller Upgrade Process and Best Practices"
Pure Storage Whitepaper: "Active/Active Controller Architecture"
Pure Storage Knowledge Base: "Minimizing Impact During Controller Upgrades"