HPE DL560 G11 AC 8SFF X4 NVME B2 4P DAC - P55316-B21

HPE P55316-B21 DL560 Gen11 8SFF x4 NVMe Bay 2 4-Port Drive Cage

Overview

The HPE P55316-B21 is a factory-new, server-specific NVMe drive cage designed for the HPE ProLiant DL560 Gen11 platform. Decoded from its product designation, this is an 8 Small Form Factor (8SFF), x4 NVMe, Bay 2, 4-port Direct Attach Connector (DAC) assembly — the hardware that allows a DL560 Gen11 chassis to physically host and connect NVMe drives in its second bay position. If you are expanding NVMe storage capacity in an existing DL560 Gen11 deployment, the P55316-B21 (often searched as P55316 B21) is the HPE-native cage that drops into the correct bay without aftermarket fitment concerns.

Key Features

• NVMe Interface: The x4 NVMe DAC connection delivers the low-latency, high-bandwidth storage connectivity that NVMe drives require — critical when running storage-intensive workloads such as database logs, VMS recording servers, or AI inference pipelines where SAS/SATA bottlenecks are unacceptable.
• 8SFF Bay 2 Placement: Designed specifically for the Small Form Factor Bay 2 position in the DL560 Gen11 chassis. This means you are adding drive slots without displacing existing Bay 1 population — incremental capacity expansion, not a rip-and-replace exercise.
• 4-Port DAC Assembly: Four NVMe ports per cage means up to four additional NVMe drives per installation. For a surveillance or compute deployment running multi-channel recording or parallel data streams, each additional NVMe port is a discrete high-speed storage lane.
• Platform-Specific Fit: HPE engineers this cage to the DL560 Gen11 mechanical and electrical spec. Using a platform-matched component avoids the power connector mismatches and backplane signal incompatibilities that generic third-party cages can introduce.

Integration & Compatibility

The P55316-B21 is built for the HPE ProLiant server line, specifically the DL560 Gen11. It is not a cross-platform component — verify your chassis generation before ordering. UNSPSC classification 26121607 confirms this as a server chassis/backplane subassembly, not a standalone drive or controller card. Pair this cage with compatible NVMe server storage drives and verify HPE's current Smart Component compatibility matrix for your specific DL560 Gen11 configuration. For broader HPE server infrastructure planning, review your data center networking and server power requirements alongside any storage expansion.

Frequently Asked Questions

Q: What server is the P55316-B21 compatible with?

A: The P55316-B21 is designed specifically for the HPE ProLiant DL560 Gen11. It is a platform-specific drive cage and should not be assumed compatible with other ProLiant generations or models without verifying HPE's compatibility documentation.

Q: What interface does the P55316-B21 use?

A: The P55316-B21 uses an NVMe (x4 DAC) interface. It is not a SAS or SATA backplane — only NVMe drives are appropriate for this cage.

Q: How many drives does the P55316-B21 support?

A: Based on the product designation, this is a 4-port assembly supporting up to four Small Form Factor (SFF) NVMe drives in Bay 2 of the DL560 Gen11.

Q: Is the P55316-B21 a factory-new HPE component?

A: Yes — the P55316-B21 is a genuine, factory-new HPE option kit sourced through established distribution channels. No grey-market, no parallel imports.

Karl Wilson

The P55316-B21 is a purpose-built NVMe drive cage for the DL560 Gen11 — not a universal bracket, not a generic backplane. The x4 NVMe DAC interface is the spec that matters most here: it means each port is a dedicated, full-bandwidth NVMe lane, not a shared SAS expander bus. That distinction is the difference between predictable low-latency storage and a shared-backplane bottleneck under simultaneous multi-drive load.

Technical Highlights:

• NVMe x4 DAC Interface: Direct-attach NVMe over x4 lanes eliminates the SAS/SATA controller hop — relevant in DL560 deployments running parallel high-throughput workloads where storage latency compounds quickly.
• 8SFF Form Factor: Small Form Factor drives give you higher drive density per rack unit compared to LFF configurations — important when the DL560 Gen11 is serving as a dense compute-plus-storage node.
• Bay 2 Specificity: This cage occupies Bay 2 of the DL560 Gen11 chassis. Confirm Bay 1 population and chassis configuration before ordering — the wrong bay assignment means a non-fitting component, not a software fix.

Deployment Considerations:

• Verify your DL560 Gen11 chassis SKU and current bay population against HPE's QuickSpecs before purchasing — Gen11 platform options are not interchangeable with Gen10 or Gen10 Plus equivalents.
• NVMe drive compatibility is not guaranteed by cage fit alone — cross-reference your intended NVMe drive SKUs against HPE's tested drive list for the DL560 Gen11 to avoid unsupported combinations.

This cage fits cleanly into a DL560 Gen11 deployment being configured for NVMe-intensive workloads — high-channel VMS recording nodes, real-time analytics servers, or edge AI inference appliances where storage throughput is a hard constraint, not an afterthought.