Appendix A: Introduction to SAS ● 91

What’s a SAS Port?

Note: Because the physical link between SAS devices is from phy to phy, rather than port to port, a “port” is more of a virtual concept, different from what is normally considered a port on other types of RAID controllers and storage devices.

A port is one or more phys. A narrow port contains one phy. A wide port typically contains four phys.

Each port has its own unique SAS address (see page 92), and all the phys in a port share that same SAS address.

SAS card port options vary. A SAS card with four phys could be configured with one wide port, with two wide ports that comprise two phys, or with four narrow ports each containing one phy. (A wide port with four phys is referred to as a 4-wideor 4x port.)

What’s a SAS Address?

Each SAS port is identified with a unique SAS address, which is shared by all phys on that port.

For example, a SAS disk drive might have two narrow ports. Each port has one unique SAS address. The single phy in each port uses its port’s SAS address.

In another example, a SAS device might have one 4-wide port. That port has one SAS address, which is shared by all four phys in the port.

Unlike SCSI devices and SCSI IDs, SAS devices self-configure their SAS addresses. User intervention is not required to set SAS addresses, and SAS addresses cannot be modified.

What’s a SAS Connector?

A SAS or mini-SAS connector is the physical plug or receptacle that you see on a SAS device. It’s what you plug a SAS cable into, or the end of the SAS cable that’s being plugged in. (See Cables on page 42.)

A connector is what forms physical links between phys. Some SAS connectors can support multiple links. The number of links a SAS connector can support is referred to as its width. Narrow connectors support a single link; wide connectors supports more than 1 link.

A single SAS device may have one or more connectors. A single SAS connector may help form links between more than two SAS devices. (For instance, as shown in the figure on page 50, the 4-wide internal SAS connector forms links with four independent disk drives.)

What do SAS Cables Look Like?

Internal standard SAS cables are narrower than internal parallel SCSI cables. The connectors vary in size depending on the number of links they support, from single link connectors to

4-wide (or larger) connectors. Internal fan-out cables let you attach four disk drives to a single 4-wide connector.

Mini-SAS connectors support both internal and external SAS connections. The mini-SAS connectors are smaller than the standard SAS internal and external connectors. Mini-SAS connectors support single and multilinks with the ability to scale to future speed needs.

For examples of some internal SAS/mini-SAS cables and an external SAS/mini-SAS cables, see Cables on page 42.

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Adaptec 2268300R manual What’s a SAS Port?, What’s a SAS Address?, What’s a SAS Connector?, What do SAS Cables Look Like?
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2268300R specifications

The Adaptec 2268300R is a robust and versatile RAID controller designed for enterprise-level storage needs. Ideal for environments demanding high availability, performance, and data protection, this controller provides organizations with the ability to manage large volumes of data while ensuring reliability.

One of the standout features of the Adaptec 2268300R is its support for various RAID levels, including RAID 0, 1, 5, 6, 10, 50, and 60. This flexibility allows users to choose the configuration that best suits their performance and redundancy requirements. By combining multiple drives into a single logical unit, the controller enhances data throughput and ensures data safety through redundancy.

The controller is built on a SATA and SAS architecture, allowing it to connect directly to both SATA and SAS drives. This broad compatibility is crucial for businesses looking to leverage existing hardware while also scaling their storage infrastructure. The Adaptec 2268300R is equipped with a powerful onboard processor that significantly boosts performance, driving down latency and increasing transaction speeds across connected drives.

Additionally, the Adaptec 2268300R features cache memory with a non-volatile option that enhances data integrity during unexpected power outages. This feature is essential for mission-critical applications where data loss can have severe repercussions. Moreover, the controller supports advanced caching algorithms, optimizing write and read performance to meet the demands of modern applications.

The controller also integrates seamlessly with Adaptec's management suite, providing users with a graphical interface to monitor and manage their storage solutions effectively. The web-based management tool allows administrators to configure RAID settings, monitor disk health, and perform troubleshooting, all from a centralized platform.

Security is another critical aspect of the Adaptec 2268300R. The controller comes equipped with encryption capabilities, enabling users to secure sensitive data at rest—protecting information from unauthorized access. Furthermore, with features like hot-spare drive support and automatic rebuilds, the controller assures continued operation even in the event of a disk failure.

In conclusion, the Adaptec 2268300R is a powerful RAID controller that delivers significant advantages in performance, flexibility, and reliability. With its support for multiple RAID levels, SAS and SATA compatibility, robust caching, and advanced management tools, it stands out as an ideal solution for businesses needing to safeguard and manage their vast data assets efficiently. Whether for enhancing data security or optimizing storage performance, the Adaptec 2268300R remains a sound choice in today’s data-driven landscape.
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