Pure Storage FlashArray-Storage-Professional Exam - Topic 3 Question 2 Discussion

When configuring NVMe/TCP (or iSCSI) for optimal performance on a Pure Storage FlashArray, configuring Jumbo Frames (an MTU of 9000) end-to-end is a standard best practice.

The command ping -M do -s 8972 <ip_addr> is specifically used to verify Jumbo Frame configuration across the network.

The -M do flag sets the 'Do Not Fragment' (DF) bit, meaning the network is not allowed to break the packet into smaller pieces.

The -s 8972 flag sets the ICMP data payload to 8972 bytes. When you add the standard 8-byte ICMP header and the 20-byte IP header, the total packet size equals exactly 9000 bytes.

If this ping command fails, it indicates that somewhere along the network path between the host (initiator) and the FlashArray (target), a switch port, router, or network interface is not configured to support an MTU of 9000. The packet is being dropped because it is too large and cannot be fragmented. The administrator must verify the MTU settings on every network hop (switches, routers, and host NICs) to resolve the issue.

Here is why the other options are incorrect:

Engage support to enable NVME/ TCP services (A): The failure of a Jumbo Frame ping test is a Layer 2/Layer 3 network configuration issue, not an indicator that the NVMe/TCP storage protocol service is disabled on the array.

Run the command from the target (C): While pinging from the FlashArray back to the host is a valid secondary troubleshooting step, it will likely also fail if the network path doesn't support Jumbo Frames. The actual resolution is to fix the MTU on the network hops.