During a hardware NDU from FlashArray//XR2 or XR3 to an XR4 model, which default service...

In the architectural evolution from FlashArray//XR2 and //XR3 to the FlashArray//XR4, Pure Storage made significant changes to the controller's rear panel and I/O design to accommodate higher performance and PCIe Gen 4 capabilities. One of the most critical changes for an Implementation Engineer to plan for during a hardware Non-Disruptive Upgrade (NDU) is the removal of the onboard, default iSCSI ports that were present on previous generations.

On //XR2 and //XR3 controllers, there were onboard Ethernet ports often used for iSCSI host connectivity without requiring a discrete PCIe adapter. However, the //XR4 controller design removes these dedicated onboard iSCSI ports to streamline the motherboard design and shift host I/O strictly to PCIe add-in cards. The //XR4 retains onboard ports specifically for Management (Mgmt) and Replication connectivity,ensuring that administrative access and array-to-array replication can still be maintained without additional hardware.

Consequently, if a customer was relying solely on the onboard ports for iSCSI traffic on their legacy //XR2 or //XR3, the Bill of Materials (BOM) for the upgrade to //XR4 must include discrete Ethernet/iSCSI PCIe cards to migrate those connections. Failure to identify this architectural difference during the pre-upgrade inventory can result in a loss of host connectivity or an inability to cable the new controllers correctly, as the expected physical ports simply will not exist on the new chassis.

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