Pass the Pure Storage FAIS FlashArray-Implementation-Specialist Questions and answers with ExamsMirror

When replacing SAS chassis data packs with DirectFlash Modules (DFMs) after an upgrade to //X20R3-EMEZZ, a DFM Swing Shelf is required to facilitate data evacuation and migration during the transition.

On an XR2/3 array, a 4-port Fibre Channel card installed in slot 1 is assigned interface names FC4 through FC7, continuing the numbering sequence from other installed FC ports.

When upgrading from a FlashArray//X to a FlashArray//XL, the hardware migration often involves handling DirectMemory Modules (DMMs) differently than standard data drives. DMMs are high-performance cache modules that reside in the controller chassis.

In this specific scenario—migrating a fully populated //X90R3 to an //XL that already has its own set of DirectFlash Modules (DFM-Ds)—the DMMs from the old chassis need to be moved to the new chassis to preserve their cache function or be properly decommissioned.

The correct procedure is toEvacuate DMMs as a datapack then install into any slot in //XL.

DMMs cannot be simply "hot-swapped" randomly while the system is live in a way that disrupts the cache map.

They must be logically grouped and evacuated (conceptually "vacated" of active data) so they can be safely removed from the old chassis.

Once removed, they can be installed into the new //XL chassis. The //XL architecture supports DMMs in specific slots, and Purity will detect and re-incorporate them into the cache pool.

This ensures that the expensive SCM (Storage Class Memory) hardware is reused in the new system without causing data integrity issues during the transition.

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After a controller upgrade or any maintenance that involves path failovers, it is critical to verify that the host multipathing software has restored connectivity to all paths and that I/O is being distributed correctly. The specific command to validate this in Purity ispurehost monitor --balance.

purehost monitor --balance: This command provides a real-time view of I/O statistics per initiator (host path). It highlights imbalances where one path might be taking zero traffic while others are overloaded, which typically indicates a pathing configuration issue, a bad cable, or a host that has not correctly rediscovered the path after the controller reboot.

purehost list simply displays configured hosts, not live performance data.

pureport list displays the status of array ports but does not show the per-host I/O distribution required to verify "balance."

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The FlashArray//XL platform features a split-chassis design with a unique PCIe bus layout compared to the standard //X series. To maintain optimal performance and redundancy, the backend connectivity for DirectFlash Shelves (DFS) must be balanced across the specific PCIe root complexes managed by the dual CPUs.

For a configuration involving multiple shelves (specifically targeting the logical shelf identifiers SH8 and SH9, which often correspond to the first pair of backend loops in an //XL deployment), the validated configuration is to usePCIe Slot 0andPCIe Slot 6. These slots are architecturally designated for the backend NVMe-oF (RoCE) fabric cards.

Using Slot 0 (typically located on the far left) and Slot 6 (located on the right side of the chassis) ensures that the I/O load is distributed across the internal midplane and CPUs correctly. Placing cards in incorrect slots (like Slot 1 or 7, which might be reserved for host I/O or inter-controller links) can result in shelf detection failures or performance bottlenecks where one CPU is overloaded with backend traffic while the other is idle.

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The FlashArray//XR4 introduces a new hardware platform architecture (internally codenamed or associated with "Cobalt" components for its BMC and chassis management). During the manufacturing and initial deployment phase, specific validation scripts are used to ensure the platform hardware is correctly initialized before the Purity Operating Environment takes over.

For a new install of a FlashArray//XR4, the Implementation Engineer is often required to runcobalt check . py(or cobalt_check.py).

This engineering-level Python script queries the Baseboard Management Controller (BMC) and internal sensors to verify that the chassis components, fans, and power delivery systems are reporting "Healthy" status specifically for the R4 architecture.

Running thisbeforepuresetup prevents the setup process from failing midway due to a hardware initialization error. It acts as a "pre-flight" hardware validation specific to the R4 generation's new chipset and management subsystem.

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If a Pure Storage Technical Support Engineer (TSE) is unavailable to immediately perform the remote health checks upon the completion of the physical installation, the correct procedure is toverify that Remote Assist (RA) is enabled and update the support casewith this information.

Standard operating procedure dictates that the Implementation Engineer must not close the install case until the array has been health-checked and verified by Support. Closing the case (Option B) would signal that the work is complete when the critical validation step is missing, potentially leaving the customer with an unverified system. Emailing the account team (Option A) is helpful for visibility but does not advance the technical workflow required to close the loop.

By confirming RA is open (using purearray remoteassist) and documenting the active session port in the case notes, the Implementation Engineer enables the Support team to perform the health checks asynchronously as soon as a TSE becomes available. This ensures the "handshake" between the onsite engineer and the remote support team is maintained without delaying the engineer's departure from the site, while guaranteeing the array will be validated before final sign-off.

To reconcile the IP configuration, the Implementation Engineer must correct the invalid netmask to the standard Class C subnet mask of255.255.255.0(Option B).

The netmask provided in the workbook, 255.255.255.223, is mathematically invalid for a subnet mask. Subnet masks function by having a continuous sequence of binary '1's followed by '0's. The decimal value 223 (binary 11011111) breaks this rule due to the zero bit in the middle of the octet. Therefore, the array initialization script would reject this value as a syntax error.

In most standard implementation scenarios where a gateway of 10.24.18.1 is provided, the intended network is a /24 (255.255.255.0), which allows for hosts 10.24.18.1 through 10.24.18.254. While Option C (/23) is a valid subnet mask, it assumes a larger network scope than is typically implied by a standard typo. Correcting the mask to the standard /24 is the safest and most logical remediation to ensure the array can communicate with the gateway and the management network.

During a hardware upgrade, physical components are often moved or handled, leading to potential connection issues. If a specific port (like CT0.ETH14) that is expected to carry traffic shows0.00 b/sand "Link Down" or similar status immediately after the controller is initialized, the most likely physical issue is an improperly seated transceiver (SFP) or cable.

The standard troubleshooting hierarchy dictates checking Layer 1 (Physical) first. Therefore, the engineer shouldensure the SFP in CT0.ETH14 is fully seated and re-seat it if necessary. SFPs can easily become slightly dislodged during the cable swap from the old controller to the new one. Checking the seating is a quick, non-disruptive step that resolves a high percentage of "dead port" issues during upgrades. Swapping to a management port (Option A) is invalid because management ports often have different speeds or configurations, and asking the customer to reboot hosts (Option B) is premature and potentially disruptive before ruling out the physical array connection.

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Hardware Non-Disruptive Upgrades (HWNDU) rely strictly on the array being in a fully healthy state before the process begins. The validate-array-health check is designed to gate the upgrade if any component that provides redundancy or data integrity is compromised. NVRAM (Non-Volatile Random Access Memory) modules are critical components in the FlashArray architecture; they store in-flight write data to ensure it is persistent before being destaged to flash.

A "Code 60" alert specifically points to a hardware issue with an NVRAM module. While the //X70 model indeed has redundancy (often using multiple NVRAM modules), proceeding with an upgrade while one is degraded puts the array at risk. During an NDU, controllers reboot and failover; running on reduced redundancy during these critical operations is not supported and is blocked by the health checks.

The correct first step for an Implementation Engineer is to attempt toreseat the unhealthy NVRAM module. Often, connection issues or transient seating faults can trigger these alerts. After reseating, the engineer must run the health check again to confirm the module status has returned to "healthy." If the module remains unhealthy after reseating, it must be replaced before the upgrade can proceed. You cannot simply disable it or ignore it, as the upgrade script will likely refuse to continue to protect data integrity.

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