During a hardware upgrade, software update, or initial deployment, FlashArray controllers are frequently rebooted. When a controller comes back online, the underlying Linux kernel boots first, followed by the proprietary Purity//FA operating system services. It is an essential responsibility of the Implementation Engineer to verify that the controller has not just powered on, but has successfully loaded its storage processes and rejoined the high-availability cluster.

The definitive Purity CLI command used to validate this state is pureadm list .

Executing pureadm list outputs a clear, tabular view of the array's cluster topology. It displays the hostname of both controllers (CT0 and CT1) and explicitly lists their current operational state.

A healthy cluster will show one controller in the "Primary" state (actively handling backend drive negotiations and primary administrative duties) and the other in the "Ready" / "Secondary" state.

If a controller has rebooted but the Purity services have not fully started, or if it is struggling to synchronize its NVRAM mirror with the primary node, pureadm list will flag that controller's status as "Offline," "Updating," or "Not Responding."

Options like pureadm status or purecluster status are fabricated syntaxes. The standard, unmodified pureadm list command is the documented best practice for verifying that Purity services have cleanly initialized and High Availability (HA) is restored.

The FlashArray//X70 (R2/R3) and FlashArray//X90 (R2/R3) require 1600W Power Supply Units (PSUs) .

Pure Storage equips its FlashArray//X chassis with different power supply capacities based on the compute load of the installed controllers:

Performance Tier (X70/X90): These models utilize high-core-count Intel Xeon processors and support the maximum density of NVMe DirectFlash Modules. To support the peak power draw of these components while maintaining N+1 redundancy (where one PSU can support the entire load), the 1600W units are mandatory.

Entry/Mid Tier (X10/X20/X50): Lower-end models often ship with 1000W or 1200W PSUs (though X50 often uses 1600W in later revisions or specific configs).

Identification: Implementation Engineers can identify these PSUs by the label on the rear handle (often color-coded or explicitly marked "1600W"). Installing an X90 controller into a chassis with older 1200W PSUs (e.g., during an improper upgrade attempt) would likely trigger a hardware alert or prevent the controllers from booting due to insufficient power budget.

At the completion of an upgrade, the correct command to manually trigger the upload of the relevant logs is purearray phonehome --send-today .

Purpose: This specific argument (--send-today) instructs the array to bundle and upload all log files generated within the current 24-hour window. This is the standard procedure post-upgrade because it ensures that all logs capturing the pre-upgrade state, the upgrade process itself, and the immediate post-upgrade health checks are transmitted to Pure Support.

Verification: This allows the Support team to validate that the upgrade completed successfully and that no dormant issues were triggered during the controller failovers.

Syntax: Option A (purelogs) is not a valid command. Option B (--send-logs) is a generic approximation, but the specific "today" flag is the best practice command cited in upgrade checklists to avoid uploading gigabytes of historical data irrelevant to the immediate event.

To enable Pure Storage Support to access the FlashArray for diagnostics, upgrades, or troubleshooting, the correct command is purearray remoteassist --connect .

Remote Assist (RA): This feature creates a secure, outbound SSH tunnel from the FlashArray to the Pure Storage support infrastructure. It allows support engineers to log in remotely without requiring the customer to open inbound firewall ports or set up a VPN.

Command Syntax:

purearray remoteassist: Running this command without arguments simply displays the current status of the session (e.g., "connected" or "disconnected") and the port number.

--connect: This is the specific flag (action) required to initiate the tunnel.

Workflow: When an Implementation Engineer is on-site and needs assistance (or is handing over for a remote upgrade), they execute this command. The output will confirm "Remote Assist enabled" and provide a session name/port, which the engineer then communicates to the Support team. The session typically stays active for a set duration (default 24 hours) or until manually disconnected (purearray remoteassist --disconnect).

Monitoring the health and status of physical hardware components is a key task during upgrades and daily administration. While the FlashArray GUI provides a visual representation, the CLI offers granular detail.

To view the specific installation status, firmware version, and health of the NVRAM modules, the correct command is purehw list --all .

purehw : This command suite is dedicated to reporting on the physical hardware components (fans, power supplies, temperature sensors, and NVRAM).

--all (or listing specific types) ensures that internal components like the NVRAM modules are displayed in the output.

The output will show the "Status" (e.g., ok, installing, updating), which is critical during a Purity upgrade or hardware replacement to confirm that the NVRAM firmware is being applied or that a new module has been successfully integrated.

puredrive list is strictly for the storage media (SSDs/DFMs), and purearray list shows high-level system info (name, ID, capacity) rather than component-level health.

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When dealing with power architecture on high-end arrays like the FlashArray//X90 R4, understanding the difference between the base chassis and the expansion shelves is critical. The base //X90 chassis—housing the powerful Intel CPUs, massive memory footprint, and primary PCIe lanes—draws significant wattage and strictly requires 200V-240V (208V minimum) power inputs to function. It will literally not power on if plugged into a 120V circuit.

However, a DirectFlash Shelf (DFS) is merely an external NVMe-oF expansion enclosure. It houses the DirectFlash Modules (DFMs) and the necessary backend I/O modules, but completely lacks the compute-heavy controllers of the main array. Because its overall power draw is significantly lower, the official Pure Storage hardware specifications state that DirectFlash Shelves are fully rated and completely supported to run on standard 120 VAC power indefinitely.

Therefore, the Implementation Engineer can confidently cable the DFS power supplies into the available 120V PDU connections without sacrificing any performance, redundancy, or hardware lifespan. It is a fully supported, permanent configuration.

The FlashArray//X20 R4 operates with a minimum AC voltage input of approximately 90 VAC .

The FlashArray//X series (specifically the entry-to-mid-range models like the X10, X20, and X50) utilizes high-efficiency Power Supply Units (PSUs) designed with auto-ranging capabilities. These PSUs conform to standard global power infrastructure requirements, supporting a nominal input range of 100V to 240V AC (50/60 Hz).

Low-Line Support: Because the X20 is an entry-level enterprise array often deployed in diverse environments (including edge locations or standard office server rooms), it fully supports "low-line" power (100-120V nominal). The technical minimum tolerance for these power supplies typically extends down to 90 VAC to account for voltage sags or fluctuations.

Contrast with High-End: Larger, higher-density systems like the FlashArray//XL or fully loaded high-performance chassis configurations often require "high-line" power (200V-240V) to deliver sufficient wattage efficiently. However, the X20 R4 does not have this restriction. Therefore, Option A (90V) represents the correct minimum floor, whereas Options B and C represent high-line voltages that are supported but not required for minimum operation.

Pure Storage DirectFlash Shelves (DFS) are designed with high-efficiency, enterprise-grade power supply units (PSUs). These PSUs are "auto-ranging," meaning they can accept a wide range of input voltages, typically from roughly 90V to 264V AC.

While data centers often prefer 208V-240V power sources for better efficiency (less heat loss and lower amperage draw for the same wattage), the hardware is fully validated and supported to operate on standard 110V/120V circuits . There is no "temporary only" restriction or hardware lockout that prevents operation on 120V.

Therefore, if the customer's high-voltage PDUs are full, the Implementation Engineer can safely connect the DirectFlash Shelf to the available 120V outlets. The shelf will function normally, provided the circuit has sufficient amperage capacity (amps) to handle the slightly higher current draw that results from using a lower voltage. This configuration is supported for the entire service life of the shelf.

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When transitioning to a significantly different hardware platform—like moving from a 3U FlashArray//X50 R3 to a 5U FlashArray//XL130 R5—customers typically leverage Pure Storage’s Evergreen storage programs (such as Ever Agile or Capacity Consolidation).

The FlashArray//XL introduces a fundamentally different chassis architecture. It requires a minimum of 20 DirectFlash Modules with distributed NVRAM (DFMDs) populated in slots 0-19 to provide the necessary write caching, completely replacing the standalone NVRAM modules found in the older //X series.

Options A and B are procedurally incorrect. While it is technically possible to retain compatible older DFMs in an //XL chassis (specifically in slots 20-39), moving drives "one at a time, allowing parity to reach 100%" is never the standard Pure Storage procedure for a hardware upgrade. Evacuating and rebuilding parity for 20 individual drives sequentially would take an exorbitant amount of time, severely degrade array performance during the continuous rebuilds, and expose the system to unnecessary data loss risks. Pure Storage does not use a drive-by-drive rebuild methodology for controller or chassis swaps.

Instead, when older capacity is being replaced, a non-disruptive upgrade (NDU) or data migration is orchestrated via Purity's upgrade scripts and array-to-array migration tools. All data is transparently migrated from the legacy //X50 R3 drives to the fully populated DFMDs/DFMs in the new //XL130 R5. Once the software verifies that the data migration phase is successfully complete, the 20 legacy DirectFlash Modules from the //X50 R3 are decommissioned and returned to Pure Storage to fulfill the trade-in agreement.

Within the Purity//FA operating system architecture, dedicated NVRAM modules (used heavily in standard non-DFMD arrays to provide non-volatile write caching) are fundamentally treated as specialized drives by the software layer. They are physically installed into specific central chassis bays labeled NVB0, NVB1, NVB2, and NVB3.

Because they are classified as drive components, the primary and most direct command an Implementation Engineer should use to verify their physical installation, health, capacity, and update status is puredrive list. When this command is executed via the CLI, it generates a comprehensive table detailing every DirectFlash Module (DFM) and NVRAM module currently seated in the chassis.

The output explicitly shows the slot location (e.g., CH0.NVB0), the component's operational status (healthy, empty, evacuating, or updating), and its specific firmware version. While the purehw list command is excellent for viewing broader chassis components (like fans, temperature sensors, and controllers), puredrive list is the purpose-built command required to monitor the precise synchronization and firmware update phases of the NVRAM modules, especially crucial during a non-disruptive upgrade (NDU) when ensuring cache mirror integrity is paramount.