Dell EqualLogic Storage

PS 4000E

The Dell EqualLogic™ PS4000 Series of virtualized iSCSI SAN arrays are designed to bring enterprise-class features, intelligence, automation and reliability to remote or branch office, departmental and small-to-medium business (SMB) storage deployments.

The PS4000 Series addresses branch office and SMB storage needs with simplified administration, rapid deployment and an affordable price, while providing a full set of enterprise-class data protection and management features, solid performance, scalability and fault-tolerance. With up to 16 SATA disk drives per modular array, the PS4000E delivers outstanding capacity value for an entry into midrange enterprise storage. To grow storage capacity and performance for remote office needs, two PS4000 arrays can be combined in a SAN group. To further scale out the SAN, EqualLogic PS6000 arrays can be added seamlessly without sacrificing the initial investment in PS4000 arrays.

All PS Series storage arrays include SAN configuration features and capabilities that sense network connections, automatically build RAID sets, and conduct system health checks to help ensure that all components are fully functional. The PS4000E is designed to be installed, configured, and serving storage in less than one hour. To improve enterprise-wide storage management, the EqualLogic SAN HeadQuarters software tool provides centralized performance and event monitoring of EqualLogic SANs across multiple sites, for instance PS4000 deployments at branch offices and PS6000 deployments in corporate data centers.

Offering built-in storage features previously available only to top-tier data centers, the PS4000E enables best-practice storage for remote, branch-office and departmental deployments. The EqualLogic PS Series arrays include the following enterprise data services and software features with no additional software licensing fees: SAN HeadQuarters Multi-SAN Historical Performance Monitoring, Auto-Replication, RAID Load Balancing, Complete SAN Virtualization, RAID Load Balancing, Storage Pools, Thin Provisioning and much more.

PS4000E Highlights:

Storage Controllers
Base Model:
Single controller with 2GB battery-backed cache memory
High-Availability Model:
Dual controllers with a total of 4GB battery-backed cache memory
Battery-backed cache provides up to 72 hours of data protection
Hard Disk Drives
Eight (8) or sixteen (16) SATA hot-pluggable hard disk drives
Drive Capacities
7,200 RPM SATA II drives available in 250GB, 500GB, or 1TB
System Capacities
2TB using eight (8) 250GB SATA disk drives
4TB using sixteen (16) 250GB SATA disk drives
8TB using sixteen (16) 500GB SATA disk drives
16TB using sixteen (16) 1TB SATA disk drives

Technical Highlights
Volumes
Up to 256
Snapshots
128 per volume / up to 2,048 total
Hosts Accessing PS Series Group
Up to 128 per pool / 256 per group
Host Protocol
Any standards compliant iSCSI initiator
Operating Systems Supported
Windows® 2000 Server
Windows Server® 2003
Windows Server® 2008 R2, including Hyper-VTM
Windows Vista®
Windows XP®
VMware® ESX Server 3 / 3.5 / 4 / ESXi 3.5
VMware® vSphereTM 4
Citrix® XenServerTM
Red Hat® Enterprise Linux®
SUSE® Linux Enterprise
Linux
SunTM Solaris
UNIX®
IBM® AIX
HP-UX
AIX®
Mac OS® X
Novell® Netware®
Virtual Iron®
RAID Support
Automatic RAID 5, RAID 6, RAID 10, and RAID 50
Network Interfaces
Two (2) GbE copper for I/O, One (1) 10/100 copper (optional management network only) per controller
TCP Network Support
IPv4, IPv6 core support
Expansion Option
Can be combined with other EqualLogic PS Series online. Only two (2) PS4000 arrays can be in a group. For more details, please see the release notes.

Reliability
Optional redundant and hot-swappable controllers
Redundant power supplies / cooling fans, and disks
Individual disk drive slot power control 
Depth: 55.1 cm / 21.7 in
Weight: 36 kg / 79.6 lb (maximum configuration)

PS 4000X

The Dell EqualLogic™ PS4000 Series of virtualized iSCSI SAN arrays are designed to bring enterprise-class features, intelligence, automation and reliability to remote or branch office, departmental and small-to-medium business (SMB) storage deployments.

The PS4000 Series addresses branch office and SMB storage needs with simplified administration, rapid deployment and an affordable price, while providing a full set of enterprise-class data protection and management features, solid performance, scalability and fault-tolerance. With 10,000 RPM SAS disk drives, the PS4000X array provides up to 9.6 TB of storage for a great balance of cost-effective performance and capacity. To grow storage capacity and performance for remote office needs, two PS4000 arrays can be combined in a SAN group. To further scale out the SAN, EqualLogic PS6000 arrays can be added seamlessly without sacrificing the initial investment in PS4000 arrays.

To help prevent both under-utilization and over-provisioning, EqualLogic PS Series arrays are based on a virtualized modular storage architecture that enables IT managers to purchase only the storage they need, when they need it. Using innovative data movement technology, all EqualLogic PS Series arrays within a SAN work together to automatically manage data, load balance across all resources, and expand to meet growing storage needs.

Offering built-in storage features previously available only to top-tier data centers, the PS4000X enables best-practice storage for remote, branch-office and departmental deployments. The EqualLogic PS Series arrays include the following enterprise data services and software features with no additional software licensing fees: SAN HeadQuarters Multi-SAN Historical Performance Monitoring, Auto-Replication, RAID Load Balancing, Complete SAN Virtualization, RAID Load Balancing, Storage Pools, Thin Provisioning and much more.

PS4000X Highlights:

Storage Controllers
Dual controllers with a total of 4GB battery-backed cache memory
Battery-backed cache provides up to 72 hours of data protection
Hard Disk Drives
Sixteen (16) or sixteen SAS hot-pluggable hard disk drives
Drive Capacities
10,000 RPM SAS drives available in 400GB, 450GB or 600GB
System Capacities
6.4TB using sixteen (16) 400GB SAS disk drives
7.2TB using sixteen (16) 450GB SAS disk drives
9.6TB using sixteen (16) 600GB SAS disk drives

Technical Highlights
Volumes
Up to 256
Snapshots
128 per volume / up to 2,048 total
Hosts Accessing PS Series Group
Up to 128 per pool / 256 per group
Host Protocol
Any standards compliant iSCSI initiator
Operating Systems Supported
Windows® 2000 Server
Windows Server® 2003
Windows Server® 2008, including Hyper-VTM
Windows Server® 2008 R2, including Hyper-VTM
Windows Vista®
Windows XP®
VMware® ESX Server 3 / 3.5 / 4 / ESXi 3.5
VMware® 4TM
Citrix® XenServerTM
Red Hat® Enterprise Linux®
SUSE® Linux Enterprise
Linux
SunTM Solaris
UNIX®
IBM® AIX
HP-UX
Mac OS® X
Virtual Iron®
Novell® Netware®
RAID Support
Automatic RAID 5, RAID 6, RAID 10, and RAID 50
Network Interfaces
Two (2) GbE copper for I/O, One (1) 10/100 copper (optional management network only) per controller
TCP Network Support
IPv4, IPv6 core support
Expansion Option
Can be combined with other EqualLogic PS Series online. Only two (2) PS4000 arrays can be in a group. For more details, please see the release notes.

Reliability
Redundant, hot-swappable controllers, power supplies / cooling fans, and disks
Individual disk drive slot power control

PS 4000XV

The Dell EqualLogic™ PS4000 Series of virtualized iSCSI SAN arrays are designed to bring enterprise-class features, intelligence, automation and reliability to remote or branch office, departmental and small-to-medium business (SMB) storage deployments.

The PS4000 Series addresses branch office and SMB storage needs with simplified administration, rapid deployment and an affordable price, while providing a full set of enterprise-class data protection and management features, solid performance, scalability and fault-tolerance. With 15,000 RPM SAS disk drives, the PS4000XV array offers the best performance in the PS4000 Series with strong random IOPS performance for branch office deployments. To grow storage capacity and performance for remote office needs, two PS4000 arrays can be combined in a SAN group. To further scale out the SAN, EqualLogic PS6000 arrays can be added seamlessly without sacrificing the initial investment in PS4000 arrays.

The PS4000XV is an intelligent storage array that is designed to provide rapid installation, simple management, and seamless expansion. All PS Series storage arrays include SAN configuration features and capabilities that sense network connections, automatically build RAID sets, and conduct system health checks to help ensure that all components are fully functional. The PS4000XV is designed to be installed, configured, and serving storage in less than one hour. To improve enterprise-wide storage management, the EqualLogic SAN HeadQuarters (SAN HQ) software tool provides centralized performance and event monitoring of EqualLogic SANs across multiple sites, for instance PS4000 deployments at branch offices and PS6000 deployments in corporate data centers.

Offering built-in storage features previously available only to top-tier data centers, the PS4000XV enables best-practice storage for remote, branch-office and departmental deployments. The EqualLogic PS Series arrays include the following enterprise data services and software features with no additional software licensing fees: SAN HeadQuarters, Multi-SAN Historical Performance Monitoring, Auto-Replication, RAID Load Balancing, Complete SAN Virtualization, RAID Load Balancing, Storage Pools, Thin Provisioning and much more.

PS4000XV Highlights:

Storage Controllers
Dual controllers with a total of 4GB battery-backed cache memory
Battery-backed cache provides up to 72 hours of data protection
Hard Disk Drives
Sixteen (16) SAS hot-pluggable hard disk drives
Drive Capacities
15,000 RPM SAS drives available in 300GB, 450GB, 600GB
System Capacities
4.8TB using sixteen (16) 300GB SAS disk drives
7.2TB using sixteen (16) 450GB SAS disk drives
9.6TB using sixteen (16) 600GB SAS disk drives

Technical Highlights
Volumes
Up to 256
Snapshots
128 per volume / up to 2,048 total
Hosts Accessing PS Series Group
Up to 128 per pool / 256 per group
Host Protocol
Any standards compliant iSCSI initiator
Operating Systems Supported
Windows® 2000 Server
Windows Server® 2003
Windows Server® 2008, including Hyper-VTM
Windows Server® 2008 R2, including Hyper-VTM
Windows Vista®
Windows XP®
VMware® ESX Server 3 / 3.5 / 4 / ESXi 3.5
VMware® vSphereTM 4
Citrix® XenServerTM
Red Hat® Enterprise Linux®
SUSE® Linux Enterprise
Linux
SunTM Solaris
UNIX®
IBM® AIX
HP-UX
Mac OS® X
Virtual Iron®
Novell® Netware®
RAID Support
Automatic RAID 5, RAID 6, RAID 10, and RAID 50
Network Interfaces
Two (2) GbE copper for I/O, One (1) 10/100 copper (optional management network only) per controller
TCP Network Support
IPv4, IPv6 core support
Expansion Option
Can be combined with other EqualLogic PS Series online. Only two (2) PS4000 arrays can be in a group. For more details, please see the release notes.

Reliability
Redundant, hot-swappable controllers, power supplies / cooling fans, and disks
Individual disk drive slot power control

PS 6000E

The PS6000E is an enterprise-class iSCSI SAN ideal for organizations looking to consolidate storage cost-effectively without sacrificing capabilities. The EqualLogic peer storage architecture delivers a capable and affordable SAN that is extremely simple to manage and has an all-inclusive software suite which helps reduce Total Cost of Ownership (TCO).

Whether you are looking for a storage solution that solves tactical problems and can easily scale to meet your strategic goals, or you know you require more than one hundred terabytes from the start, the PS6000E’s modular scalability can assure you a SAN to fit your needs.

The PS6000E line spans from 2 to 16TB in capacity in a single array, utilizing SATA drives ranging from 250GB to 1TB. It is built from fully redundant, hot-swappable enterprise hardware. For applications that don’t demand mission-critical redundancy, there are dual controller configurations of the PS6000E that make it even more cost-effective. Built-in software functionality includes SAN HQ Multi-SAN historical performance monitoring, automatic load balancing, Microsoft and VMware application integration, snapshots and replication, multi-path I/O, consistency sets, thin provisioning and much more.

Seamlessly integrated with all other PS Series storage arrays, the PS6000E expands your ability to optimize performance and capacity using storage pools and tiers matched to application demands. And with online data movement between tiers, you gain flexibility to adjust without disruption as your business evolves.

PS6000E Highlights:

Storage Controllers
Base Model
Single controller with 2GB battery-backed cache memory, only available with 250GB disk drive options

High-Availability Model
Dual controllers with a total of 4GB battery-backed cache memory
Battery-backed cache provides up to 72 hours of data protection

Hard Disk Drives
Eight (8) or Sixteen (16) SATA hot-pluggable hard disk drives

Drive Capacities
7,200 RPM SATA II drives available in 250GB, 500GB or 1TB

System Capacities
Base Model
2TB using eight (8) 250GB SATA disk drives
4TB using sixteen (16) 250GB SATA disk drives

High-Availability Model
4TB using sixteen (8) 250GB SATA disk drives
8TB using sixteen (16) 500GB SATA disk drives
16TB using sixteen (16) 1TB SATA disk drives

Technical Highlights:

Volumes
Up to 1,024

Snapshots
512 per volume / up to 10,000 total

Hosts Accessing PS Series Group Up to 512 per pool / 2,048 per group

Host Protocol
Any standards compliant iSCSI initiator

Operating Systems Supported

• Windows® 2000 Server
• Windows Server® 2003
• Windows Server® 2008, including Hyper-V™
• VMware® ESX Server 3 / 3.5 / ESXi 3.5
• Citrix® XenServer™
• Red Hat® Enterprise Linux®
• SUSE® Linux Enterprise
• Linux
• SunTM Solaris™
• UNIX®
• IBM® AIX
• HP-UX®
• Mac OS® X
• Novell® Netware®

RAID Support
Automatic RAID 5, RAID 6, RAID 10, and RAID 50

GbE Network Interfaces
Four (4) copper

TCP Network Support
IPv4, IPv6 core support including JITC

Expansion Option
Can be combined with other EqualLogic PS Series arrays in the same SAN group online

Reliability

Redundant, hot-swappable controllers, power supplies / cooling fans, and disks
Individual disk drive slot power control

PS 6000X

Databases, email and virtual servers require large capacity and demand high performance storage. Dell’s EqualLogic PS6000X offers 10,000 RPM Serial Attached SCSI (SAS) disk drives to meet this need.

With a 16 drive chassis full of 400GB SAS drives, the PS6000X array delivers a 6.4TB iSCSI storage array built on fully-redundant, hot-swappable enterprise hardware. Scale out capacity and performance by adding additional arrays for a virtualized iSCSI SAN. Built-in software functionality includes SAN HQ Multi-SAN historical performance monitoring, automatic load balancing, Microsoft and VMware application integration, snapshots and replication, multi-path I/O, consistency sets, and much more.

Seamlessly integrated with all other EqualLogic PS Series storage arrays, the PS6000X expands your ability to optimize performance and capacity using storage pools and tiers matched to application demands. And with online data movement between tiers, you gain flexibility to adjust without disruption as your business evolves. The PS6000X offers Reduce TCO with the PS Series’ all-inclusive, SAN management software & ease of management. The Dell EqualLogic family of proven, high-performance, self-managing storage arrays is designed to meet the requirements of any SAN environment.

PS6000X Highlights:

Storage Controllers
Single controller with 4GB battery-backed cache memory
Battery-backed cache provides up to 72 hours of data protection

Hard Disk Drives
Sixteen (16) SAS hot-pluggable hard disk drives

Drive Capacities
10,000 RPM SAS drives available in 400GB

System Capacities
7.2TB using sixteen (16) 450GB SAS disk drives and 9.6TB using sixteen (16) 600GB SAS disk drives

Technical Highlights

Volumes
Up to 1,024

Snapshots
512 per volume / up to 10,000 total

Hosts Accessing PS Series Group
Up to 512 per pool / 2,048 per group

Host Protocol
Any standards compliant iSCSI initiator

Operating Systems Supported

• Windows® 2000 Server
• Windows Server® 2003
• Windows Server® 2008, including Hyper-V™
• VMware® ESX Server 3 / 3.5 / ESXi 3.5
• Citrix® XenSource™
• Red Hat® Enterprise Linux®
• SUSE® Linux Enterprise
• Linux
• SunTM Solaris™
• UNIX®
• IBM® AIX
• HP-UX®
• Mac OS® X
• Novell® Netware®

RAID Support
Automatic RAID 5, RAID 6, RAID 10, and RAID 50

GbE Network Interfaces
Four (4) copper

TCP Network Support
IPv4, IPv6 core support including JITC

Expansion Option
Can be combined with other EqualLogic PS Series arrays in the same SAN group online

Reliability

Redundant, hot-swappable controllers, power supplies / cooling fans, and disks
Individual disk drive slot power control

PS 6000XV

Dell’s EqualLogic PS6000XV is an enterprise-class iSCSI SAN array ideal for organizations looking for the highest-performance tier of HDD storage for business-critical applications. The EqualLogic peer storage architecture delivers a self-optimizing SAN that is extremely simple to manage and has an all-inclusive software suite to help reduce TCO. The PS6000XV uses 15,000 RPM Serial Attached SCSI (SAS) disk drives and to deliver high performance for databases and online transaction processing applications.

With a 16 drive chassis full of 450 GB SAS drives, the PS6000X array delivers a 7.2 TB iSCSI storage array built on fully-redundant, hot-swappable enterprise hardware. Scale out capacity and performance by adding additional arrays for a virtualized iSCSI SAN. Built-in software functionality includes SAN HQ Multi-SAN historical performance monitoring, automated load balancing, Microsoft and VMware application integration, SAN HQ Multi-SAN historical performance monitoring, snapshots and replication, multi-path I/O, consistency sets, and much more.

Seamlessly integrated with all other EqualLogic PS Series storage arrays, the PS6000X expands your ability to optimize performance and capacity using storage pools and tiers matched to application demands. And with online data movement between tiers, you gain flexibility to adjust without disruption as your business evolves.

PS6000XV Highlights:

Storage Controllers
Dual controller with 4GB battery-backed cache memory
Battery-backed cache provides up to 72 hours of data protection

Hard Disk Drives
Sixteen (16) SAS hot-pluggable hard disk drives

Drive Capacities
15,000 RPM SAS drives available in 300GB, 450GB

System Capacities
4.8TB using sixteen (16) 300GB SAS disk drives
7.2TB using sixteen (16) 450GB SAS disk drives

Technical Highlights

Volumes
Up to 1,024

Snapshots
512 per volume / up to 10,000 total

Hosts Accessing PS Series Group
Up to 512 per pool / 2,048 per group

Host Protocol
Any standards compliant iSCSI initiator

Operating Systems Supported

• Windows® 2000 Server
• Windows Server® 2003
• Windows Server® 2008, including Hyper-V™
• VMware® ESX Server 3 / 3.5 / ESXi 3.5
• Citrix® XenSource™
• Red Hat® Enterprise Linux®
• SUSE® Linux Enterprise
• Linux
• SunTM Solaris™
• UNIX®
• IBM® AIX
• HP-UX®
• Mac OS® X
• Novell® Netware®

RAID Support
Automatic RAID 5, RAID 6, RAID 10, and RAID 50

GbE Network Interfaces
Four (4) copper

TCP Network Support
IPv4, IPv6 core support including JITC

Expansion Option
Can be combined with other EqualLogic PS Series arrays in the same SAN group online

Reliability

Redundant, hot-swappable controllers, power supplies / cooling fans, and disks
Individual disk drive slot power control

PS 6000S

The Dell EqualLogic PS6000S is an enterprise-class iSCSI SAN array ideal for organizations looking for an affordable and easy means to bring the low latency performance benefits of SSD technology to your demanding applications. The PS6000S provides higher IOPS and as little as 1/3rd the latency of 15K rpm disk arrays for challenging applications, such as Oracle or SQL tempdb databases or virtual desktop implementations such as VMware View with linked clone technology.

With Solid State Drives (SSD) the PS6000S array provides low-latency, high-IOPS transactional performance. Scale out with other PS6000s arrays for additional SSD performance or with other PS6000 and PS5000 series arrays for a tiered SAN. Built-in software functionality includes SAN HQ Multi-SAN historical performance monitoring, automated load balancing, Microsoft and VMware application integration, SAN HQ Multi-SAN historical performance monitoring, snapshots and replication, multi-path I/O, consistency sets, and much more.

Seamlessly integrated with all other EqualLogic PS Series storage arrays, the PS6000S with SSD drives is the ideal choice for organizations looking for affordable access to low latency and high-I/O storage. And with online data movement between tiers, you gain flexibility to adjust without disruption as your business evolves.

PS6000S Highlights:

Storage Controllers
Dual controller with 4GB battery-backed cache memory
Battery-backed cache provides up to 72 hours of data protection

Hard Disk Drives
Eight (8) or Sixteen (16) hot-pluggable Solid State Drives (SSD)

Drive Capacities
50GB1 Solid State Drives (SSD)

System Capacities
400GB using eight (8) 50GB SSD disk drives
800GB using sixteen (16) 50GB SSD disk drives

Technical Highlights

Volumes
Up to 1,024

Snapshots
512 per volume / up to 10,000 total

Hosts Accessing PS Series Group
Up to 512 per pool / 2,048 per group

Host Protocol
Any standards compliant iSCSI initiator

Operating Systems Supported

• Windows® 2000 Server
• Windows Server® 2003
• Windows Server® 2008, including Hyper-V™
• VMware® ESX Server 3 / 3.5 / ESXi 3.5
• Citrix® XenSource™
• Red Hat® Enterprise Linux®
• SUSE® Linux Enterprise
• Linux
• SunTM Solaris™
• UNIX®
• IBM® AIX
• HP-UX®
• Mac OS® X
• Novell® Netware®

RAID Support
Automatic RAID 5, RAID 6, RAID 10, and RAID 50

GbE Network Interfaces
Four (4) copper

TCP Network Support
IPv4, IPv6 core support including JITC

Expansion Option
Can be combined with other EqualLogic PS Series arrays in the same SAN group online

Reliability

Redundant, hot-swappable controllers, power supplies / cooling fans, and disks
Individual disk drive slot power control

PS 6500E

Dell’s EqualLogic PS6500E virtualized architecture combines with dense SATA package for affordable, enterprise-capable tiered storage. Like the rest of the EqualLogic product family, it combines combines intelligence and automation with fault tolerance to provide simplified administration, rapid deployment, enterprise performance and reliability, and seamless scalability.

The PS6500E delivers the lowest cost-per-gigabyte in the EqualLogic family with up to 48 TB of SATA storage in a high-density 4U chassis. A PS Series SAN built with PS6500E arrays can scale up to 576 TB under a single, intuitive management interface. The PS6000 line features a re-designed controller with a fourth Gigabit Ethernet port that can deliver improved sequential read and write performance compared to previous generations.

EqualLogic PS Series arrays are based on a virtualized modular storage architecture that enables IT managers to purchase only the storage they need, when they need it — preventing both underutilization and over-provisioning. Using innovative data movement technology, all EqualLogic PS Series arrays in a SAN work together to automatically manage data, load balance across all resources, and expand to meet growing storage needs.

Dell’s portfolio of EqualLogic arrays are designed to meet and exceed the rugged requirements of today’s data center. The PS6500E includes fault tolerance capabilities through fully redundant and hot-swappable components — dual-controllers, triple fan trays and power supplies, and disk drives with hot spares.

With built-in storage features once available only to top-tier data centers, the PS6500E enables best practice storage for every size organization. The EqualLogic PS Series arrays include automatic load balancing, snapshots and replication, Microsoft application integration, hypervisor-aware snapshots for VMware, multi-path I/O, consistency sets, and much more.

PS6500E Highlights:

Storage Controllers
Dual controller with 4GB battery-backed cache memory
Battery-backed cache provides up to 72 hours of data protection

Hard Disk Drives
Forty-eight (48) SATA hot-pluggable hard disk drives

Drive Capacities
7,200 RPM SATA II drives available in 500GB, or 1TB

System Capacities
24TB using forty-eight (48) 500GB SATA disk drives
48TB using forty-eight (48) 1TB SATA disk drives

Technical Highlights

Volumes
Up to 1,024

Snapshots
512 per volume / up to 10,000 total

Hosts Accessing PS Series Group
Up to 512 per pool / 2,048 per group

Host Protocol
Any standards compliant iSCSI initiator

Operating Systems Supported

• Windows® 2000 Server
• Windows Server® 2003
• Windows Server® 2008, including Hyper-V™
• VMware® ESX Server 3 / 3.5 / ESXi 3.5
• Citrix® XenSource™
• Red Hat® Enterprise Linux®
• SUSE® Linux Enterprise
• Linux
• SunTM Solaris™
• UNIX®
• IBM® AIX
• HP-UX®
• Mac OS® X
• Novell® Netware®

RAID Support
Automatic RAID 5, RAID 6, RAID 10, and RAID 50

GbE Network Interfaces
Four (4) copper

TCP Network Support
IPv4, IPv6 core support including JITC

Expansion Option
Can be combined with other EqualLogic PS Series arrays in the same SAN group online

Reliability

Redundant, hot-swappable controllers, power supplies / cooling fans, and disks
Individual disk drive slot power control