P74945-001 HPE MR408i-p 4GB Cache PCI SPDM Gen11 x8 Lanes Plug-in Storage Controller

HPE MR408i-p Gen11 Plug-in Storage Controller 

The HPE P74945-001 MR408i-p SPDM PCIe Gen4 storage controller is engineered for modern Gen11 servers requiring compact, high-throughput, and secure storage expansion. Built on a Broadcom Aero ASIC platform, this controller delivers consistent performance while maintaining flexible drive connectivity across NVMe, SAS, and SATA infrastructures.

General Information

• Manufacturer: Hewlett Packard Enterprise (HPE)
• Part Number: P74945-001
• PCIe Gen4 x8 lane interface for high-speed connectivity
• Designed for enterprise-grade storage workloads

Bandwidth and Performance Metrics

• Up to 13.7 GB/s data transfer capacity
• Eight PCI Express Gen4.0 lanes
• Up to 3 million random read IOPS
• RAID 5 random write performance reaching 240K IOPS

Hardware-Level Security Enhancements

• Silicon Root of Trust for firmware validation
• Compatibility with self-encrypting drives
• Protection against unauthorized firmware tampering

Modern Authentication Standards

• DMTF SPDM certificate-based authentication
• Seamless integration with HPE iLO 6

Management and Monitoring Tools

• Command Line Interface (CLI)
• Web-based control panel
• Out-of-band remote management
• Redfish and UEFI configuration support

Operating System Compatibility

• Microsoft Windows Server
• Linux distributions
• VMware virtualization platforms

Available Controller Designs

• Standard PCI Half Height / Half Length (HH/HL)
• OCP NIC 3.0 form factor options

Supported Models by Form Type

• MR216i-p and MR416i-p – PCI standard
• MR216i-o, MR408i-o, MR408i-p, MR416i-o – OCP NIC 3.0

Port Configuration Options

• MR408i-p: 1 x 8 SlimSAS port
• MR408i-o: 1 x 8 low-profile SlimSAS
• MR216i-p: 2 x 8 SlimSAS
• MR216i-o: 2 x 8 low-profile SlimSAS
• MR416i-p: 2 x 8 SlimSAS
• MR416i-o: 2 x 8 low-profile SlimSAS

Cache Memory Configuration

Integrated Cache by Model

• MR408i-p: 4 GB cache
• MR408i-o: 4 GB cache
• MR416i-p: 8 GB cache
• MR416i-o: 8 GB cache
• MR216i-p: No cache
• MR216i-o: No cache

Advanced RAID Levels

• RAID 0, 1, 5, 6, 10
• RAID 50 and RAID 60 for enhanced fault tolerance

Entry-Level RAID Configurations

• RAID 0
• RAID 1
• RAID 10

Encrypted Drive Readiness

• Supports secure encrypted storage devices
• Improves data protection for sensitive workloads

The Core Architecture of the MR408i-p Controller

The HPE MR408i-p is built upon a sophisticated architecture that leverages the latest interconnect technologies and intelligent data processing. Understanding its core components is key to appreciating its role within the server ecosystem. 

SPDM in Action with the MR216i-o

During server boot or at runtime, the HPE server platform can initiate an SPDM session with the MR408i-p controller. The controller responds with signed certificates and measurements that prove its authenticity as a genuine HPE component. This process is transparent to the operating system but is fundamental to a Zero Trust hardware architecture. It provides assurance that the storage data path is rooted in a trusted hardware component.

PCI Express Gen11 x8 Lanes: The High-Speed Data Highway

The controller utilizes a PCI Express (PCIe) Gen11 interface with eight data lanes. This modern PCIe generation provides a significant leap in per-lane bandwidth compared to previous generations. At the heart of the MR408i-p's performance is its generous 4GB of DDR4 cache memory. This is not ordinary RAM; it's a protected, high-speed buffer for data in transit.

Smart Storage Processor (SPDM): The Onboard Intelligence

The "SPDM" in the product name refers to the dedicated Smart Storage Processor. This specialized ASIC (Application-Specific Integrated Circuit) offloads all RAID computation and storage management tasks from the server's main CPUs.

Defining Features and Enterprise Capabilities

The HPE MR408i-p is distinguished by a suite of features that cater specifically to the reliability, manageability, and performance needs of enterprise data centers. This controller supports a comprehensive array of RAID levels, allowing administrators to tailor data protection and performance to specific application needs.

Target Use Cases and Deployment Scenarios

The HPE MR408i-p is not a one-size-fits-all component; its capabilities make it ideally suited for specific server roles and applications. Database performance is often I/O-bound. The MR408i-p's large cache and hardware RAID acceleration significantly reduce transaction latency and improve query response times for relational databases. Hypervisors generate random I/O patterns from multiple virtual machines. The controller's adaptive caching and robust RAID protection (like RAID 10 or 6) ensure consistent performance and data safety for virtualized workloads.

High-Performance File and Application Servers

When deployed in a server acting as a file server or as the storage backend for a scale-out NAS solution, the controller provides the necessary throughput and reliability for concurrent user access. Applications like Microsoft Exchange benefit from the fast write performance ensured by the FBWC and the high availability provided by redundant RAID configurations.

Software-Defined Storage (SDS) and Hyper converged Infrastructure (HCI)

In SDS or HCI nodes, where local storage is pooled into a distributed system, the P74945-001 MR408i-p provides a reliable, high-performance hardware abstraction layer. Its advanced features ensure that the underlying physical storage is both fast and resilient, forming a solid foundation for the software-defined layer.

Firmware

For optimal stability and feature support, it is imperative to use the HPE-provided firmware and drivers. These are available through the HPE Support Center and are often bundled in HPE Service Packs for ProLiant (SPP). Consistent firmware levels across the server ecosystem help prevent interoperability issues. The included 4GB Flash-Backed Write Cache module is a critical component. Administrators should monitor its health via HPE SSA or iLO. The flash-backup system ensures data persistence without the maintenance requirements of older battery-backed cache units.

Category: MR408i-p vs. Other Options

Understanding where the P74945-001 MR408i-p fits within HPE's controller portfolio helps in making an informed selection. HPE often offers controllers in varying cache sizes (e.g., 2GB, 4GB, 8GB). The 4GB cache of the MR408i-p represents a balanced, mainstream enterprise choice suitable for a wide range of mixed workloads. Applications with extremely write-intensive profiles might benefit from a larger cache.

Internal vs. External Controllers

The P74945-001 MR408i-p is an internal storage controller, designed to manage drives within the server chassis or directly attached internal enclosures. For connecting to external storage shelves (JBODs), an HPE controller with external SAS ports (e.g., an "e" model like the MR416i-e) would be required.

RAID vs. HBA Mode

While the P74945-001 MR408i-p is a premier RAID controller, it can often be configured in "HBA Mode" or "Non-RAID Mode." This disables the hardware RAID features and presents all drives individually to the operating system, which is a requirement for many software-defined storage solutions like vSAN or Ceph that manage redundancy in software.

Compatibility

The P74945-001 is specifically designed for HPE ProLiant Gen11 servers. It is crucial to verify compatibility with the specific server model (e.g., ProLiant DL, ML, or XL series) using the HPE Quick Specs or the HPE Compatibility Matrix. Using a Gen11 controller in an older generation server, or vice versa, will likely result in incompatibility. The MR408i-p typically features internal SAS connectors (likely SFF-8654 or similar for Gen11). Proper SAS cables are required to connect the controller to the server's drive backplane or to external storage enclosures. Correct cable selection is vital for signal integrity and performance. The category of intelligent, cache-equipped PCIe storage controllers, exemplified by the HPE P74945-001 MR408i-p, remains a cornerstone of enterprise IT infrastructure. In an era of increasing software-defined capabilities, this hardware provides a vital layer of performance, data integrity, and manageability that pure software solutions cannot fully replicate without consuming host resources.