• Disk-array enclosures

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    Disk-array enclosures

    General information on front-loading DAEs

    Each DAE with front facing drives typically consists of the following components:

    • Drive carrier
    • Disk drive
    • Midplane
    • Link control cards (LCCs)
    • Power supply/cooling modules
    • EMI shielding
    Drive carrier

    The disk drive carriers are metal and plastic assemblies that provide smooth, reliable contact with the enclosure slot guides and midplane connectors. Each carrier has a handle with a latch and spring clips. The latch holds the disk drive in place to ensure proper connection with the midplane. Disk drive activity/fault LEDs are integrated into the carrier.

    Disk drives

    Each disk drive consists of one disk drive in a carrier. You can visually distinguish between disk drive types by their different latch and handle mechanisms and by type, capacity, and speed labels on each disk drive. You can add or remove a disk drive while the DAE is powered up, but you should exercise special care when removing disk drives while they are in use. Disk drives are extremely sensitive electronic components.

    Midplane

    A midplane separates the front-facing disk drives from the rear-facing LCCs and power supply/cooling modules. It distributes power and signals to all components in the enclosure. LCCs, power supply/cooling modules, and disk drives plug directly into the midplane.

    Link control cards (LCCs)

    An LCC supports, controls, and monitors the DAE, and is the primary interconnect management element. Each LCC includes connectors for input and expansion to downstream devices. An enclosure address (EA) indicator is located on each LCC. Each LCC also includes a bus (loop) identification indicator.

    Power supply/cooling modules

    The power supply/cooling module integrates independent power supply and blower cooling assemblies into a single module.

    Each power supply is an auto-ranging power-factor-corrected, multi-output, off-line converter with its own line cord. The drives and LCC have individual soft-start switches that protect the disk drives and LCC if you install them while the disk enclosure is powered up. A disk or blower with power-related faults will not affect the operation of any other device.

    Each power/cooling module has three status LEDs.

    EMI shielding

    EMI compliance requires a properly installed electromagnetic interference (EMI) shield in front of the DAE disk drives. When installed in cabinets that include a front door, the DAE includes a simple EMI shield. Other installations require a front bezel that has a locking latch and integrated EMI shield. You must remove the bezel/shield to remove and install the disk drive modules.

    Disk drive type

    Serial Attached SCSI (SAS) and Flash (solid state disk drives with flash memory, or SSD) disk drives are 12-volt, and support the SAS interface. Firmware and drive carriers are unique to EMC.

    2U, 25 (2.5-inch) DAE

    The 25 (2.5-inch) disk drive DAE is 2 rack units (U), 3.40 inches, high and includes slots for 25 2.5-inch disk drives. It uses a 12-Gb/s SAS interface for communication between the storage processors (SPs) and the DAE.

    Review the following sections for details on the components and LEDs comprising this DAE.

    2U, 25-drive DAE front view

    On the front, the 2U, 25 disk drive DAE includes the following components:

    • Disk drives in 2.5-inch carriers (hot-swappable)
    • Status LEDs

    Figure 1 shows the location of these components.

    Figure 1. Example of a 2U, 25 (2.5-inch) disk drive DAE (front view)
    12Gb/s 25-drive DAE front view with callouts
    Table 1. 2U, 25-drive DAE descriptions
    Location
    Description
    Location
    Description
    2.5-inch 6-Gb/s SAS drives
    Disk drive fault LED (amber)
    DAE fault LED (amber)
    Disk drive status/activity (blue)
    DAE power status LED (blue)

    Table 2 describes the 2U, 25 (2.5-inch) DAE and disk drive status LEDs.

    Table 2. 2U, 25-drive DAE and disk drive status LEDs
    LED
    Location
    Color
    State
    Description
    DAE fault
    Blue
    On
    No fault has occurred
    Amber
    On
    Fault has occurred
    DAE power
    Blue
    On
    Powering and powered up
    Off
    Powered down
    Disk drive fault
    Amber
    On
    Fault has occurred
    Off
    No fault has occurred
    Disk drive on/activity
    Blue
    On
    Powering and powered up
    Blinking
    Disk drive activity

    2U, 25 (2.5-inch) rear view

    On the rear of a 2U, 25 (2.5-inch) DAE are the following components:

    • Two 12-Gb/s SAS link control cards (LCC); A () and B ()
    • Two power supply/cooling modules; A () and B ()
    Figure 2. 2U, 25-drive DAE rear component locations
    12Gb/s 25-drive DAE rear components with callouts

    2U, 25-drive DAE LCC

    LCC functions and features

    The LCC supports, controls, and monitors the DAE, and is the primary interconnect management element. Each LCC includes connectors for input and output to downstream devices.

    The LCCs in a DAE connects to the storage processors and other DAEs. The cables connect the LCCs in a system in a daisy-chain topology.

    Internally, each DAE LCC uses protocols to emulate a loop; it connects to the drives in its enclosure in a point-to-point fashion through a switch. The LCC independently receives and electrically terminates incoming signals. For traffic from the system's storage processors, the LCC switch passes the signal from the input port to the drive being accessed; the switch then forwards the drive output signal to the port.

    Each LCC independently monitors the environmental status of the entire enclosure, using a microcomputer-controlled monitor program. The monitor communicates the status to the storage processor, which polls disk enclosure status. LCC firmware also controls the SAS Phys and the disk-module status LEDs.

    An enclosure ID, sometimes referred to as the enclosure address (EA), indicator is located on each LCC. Each LCC also includes a bus (back-end port) identification indicator. The SP initializes the bus ID when the operating system is loaded.

    12-Gb/s LCC ports, LEDs, and connectors

    Each 3U, 15 (3.5-inch) DAE LCC shows the following ports, LEDs, and connectors:

    Figure 3. 2U, 25-drive DAE LCC ports, LEDs, and connectors
    12Gb/s 25-drive DAE LCC with callouts
    Table 3. 2U, 25 (2.5-inch) DAE LCC descriptions
    Location
    Description
    Location
    Description
    Ejector latch handles
    LCC power LED
    LCC fault LED
    Enclosure ID display
    LCC management port (RJ-12) (not used)
    12-Gb/s SAS ports
    Back-end (BE) bus ID display
    SAS port status LED
    Table 4. 12-Gb/s LCC LEDs
    LED
    Location
    Color
    State
    Description
    LCC fault LED
    Amber
    On
    Fault within the LCC
    Off
    No fault or powered off
    LCC power LED
    Blue
    On
    Powered on and no fault
    Off
    Powered off
    SAS port status LED
    Amber
    On
    SAS port faulted
    Blue
    On
    SAS port linked up
    Off
    No connector in port

    2U, 25-drive DAE power supply and cooling module

    Power supply and cooling module functions and features

    The power supply/cooling modules are located to the left and right of the LCCs. The units integrate independent power supply and two dual-blower cooling assemblies into a single module.

    Each power supply is an auto-ranging, power-factor-corrected, multi-output, offline converter with its own line cord. Each supply supports a fully configured DAE and shares load currents with the other supply. The drives and LCCs have individual soft-start switches that protect the disk drives and LCCs if they are installed while the disk enclosure is powered up. The enclosure cooling system includes two dual-blower modules.

    Power supply and cooling module connectors and LEDs

    Figure 4 shows an example of a 2U, 25-drive DAE AC power supply/cooling module with a power in (recessed) connector (plug) and status LEDs.

    Figure 4. 2U, 25-drive DAE AC power supply and cooling module
    12Gb/s 25-drive DAE power supply and cooling module with callouts
    Table 5. 2U, 25 (2.5-inch) DAE descriptions
    Location
    Description
    Location
    Description
    Ejector latch handle
    Power supply/cooling module fault LED
    AC power LED (input)
    Grounding screw
    DC power LED (output)
    LCC B AC power supply power in (recessed plug)
    Table 6. 2U, 25-drive DAE AC power supply/cooling module LEDs
    LED
    Location
    Color
    State
    Description
    AC power LED (input)
    Green
    On
    AC power on
    Off
    AC power off, verify source power
    DC power LED (output)
    Green
    On
    DC power on
    Off
    DC power off, verify source power
    Power supply/cooling module fault LED
    Amber
    On
    Fault
    Blinking
    During power shutdown and during overvoltage (OVP) and undervoltage protection (UVP) fault
    Off
    No fault or power off

    3U, 15 (3.5-inch) DAE

    The 15 (3.5-inch) disk drive DAE is 3 rack units (U), 5.25 inches, high and includes slots for 15 3.5-inch disk drives. It uses a 12-Gb/s SAS interface for communication between the storage processors (SPs) and the DAE.

    Review the following sections for details on the components and LEDs comprising this DAE.

    3U, 15-drive DAE Front view

    On the front, the 3U, 15 disk drive DAE includes the following components:

    • Disk drives in 3.5-inch carriers (hot-swappable)
    • Status LEDs

    Figure 5 shows the location of these components.

    Figure 5. Example of a 3U, 15 disk drive DAE (front view)
    15-drive DAE front view with callouts
    Table 7. 3U, 15-drive DAE descriptions
    Location
    Description
    Location
    Description
    3.5-inch disk drive carriers that hold 2.5- or 3.5-inch disk drives
    Disk drive fault LED
    DAE fault LED
    Disk drive on/activity LED
    DAE power on LED

    Table 8 describes the 2U, 25 (2.5-inch) DAE and disk drive status LEDs.

    Table 8. 3U, 15 disk drive DAE and disk drive LEDs
    LED
    Location
    Color
    State
    Description
    DAE fault
    Amber
    On
    Fault has occurred within DAE
    DAE power
    Blue
    On
    Enclosure power on (main voltage)
    Off
    Enclosure power off
    Disk drive fault
    Amber
    On
    Fault has occurred
    Off
    No fault has occurred
    Disk drive on/activity
    Blue
    On
    Powering and powered up
    Blinking
    Disk drive activity
    Off
    Powered down

    3U, 15-drive DAE rear view

    On the rear, the 3U, 15-drive DAE includes the following components:

    • Two 12-Gb/s SAS link control cards (LCC); A () and B ()
    • Two power supply/cooling modules; A () and B ()

    The 3U, 15-drive DAE rear components are redundantly distributed across two sides, A and B. When viewed from behind, the top two components make up the B-side of the DAE, and the bottom two components make up the A-side.

    Figure 6 shows an example of the rear view of a 3U, 15-drive DAE.

    Figure 6. 3U, 15-drive DAE rear component locations
    15-drive DAE component locations with callouts

    3U, 15-drive DAE LCC

    Link control card functions and features

    The LCC supports, controls, and monitors the DAE, and is the primary interconnect management element. Each LCC includes connectors for input and output to downstream devices.

    The LCCs in a DAE connects to the storage processors and other DAEs. The cables connect the LCCs in a system in a daisy-chain topology.

    Internally, each DAE LCC uses protocols to emulate a loop; it connects to the drives in its enclosure in a point-to-point fashion through a switch. The LCC independently receives and electrically terminates incoming signals. For traffic from the system's storage processors, the LCC switch passes the signal from the input port to the drive being accessed; the switch then forwards the drive output signal to the port.

    Each LCC independently monitors the environmental status of the entire enclosure, using a microcomputer-controlled monitor program. The monitor communicates the status to the storage processor, which polls disk enclosure status. LCC firmware also controls the SAS Phys and the disk-module status LEDs.

    An enclosure ID, sometimes referred to as the enclosure address (EA), indicator is located on each LCC. Each LCC also includes a bus (back-end port) identification indicator. The SP initializes the bus ID when the operating system is loaded.

    3U, 15-drive DAE LCC connectors and LEDs

    Each 3U, 15 (3.5-inch) DAE LCC shows the following ports, LEDs, and connectors:

    Figure 7. 12-Gb/s LCC ports, LEDs, and connectors
    LCC physical description with callouts
    Table 9. 12-Gb/s LCC ports, LEDs, and connectors
    Location
    Description
    Location
    Description
    LCC management port (RJ-12) (not used)
    Captive screw
    12-Gb/s SAS ports
    Part number label
    Enclosure ID display
    LCC power LED
    LCC fault LED
    SAS port status LED
    Back-end (BE) bus ID display

    Review Table 12 for the LED descriptions and status meanings.

    Table 10. 12-Gb/s LCC LEDs
    LED
    Location
    Color
    State
    Description
    LCC fault LED
    Amber
    On
    Fault within the LCC
    Off
    No fault or powered off
    LCC power LED
    Blue
    On
    Powered on and no fault
    Off
    Powered off
    SAS port status LED
    Amber
    On
    SAS port faulted
    Blue
    On
    SAS port linked up
    Off
    No connector in port

    3U, 15-drive DAE power supply and cooling module

    Power supply and cooling module functions and features

    The power supply/cooling modules are located above and below the LCCs. The units integrate independent power supply and dual-blower cooling assemblies into a single module.

    Each power supply is an auto-ranging, power-factor-corrected, multi-output, offline converter with its own line cord. Each supply supports a fully configured DAE and shares load currents with the other supply. The drives and LCCs have individual soft-start switches that protect the disk drives and LCCs if they are installed while the disk enclosure is powered up. The enclosure cooling system includes two dual-blower modules.

    Power supply and cooling module connectors and LEDs

    Figure 8 shows an example of the 3U 15 (3.5 inch) disk drive DAE AC power supply/cooling module with a power in (recessed) connector (plug) and status LEDs.

    Figure 8. 3U, 15-drive DAE power supply and cooling module
    Power supply and cooling module Illustration with callouts
    Table 11. 3U 15 disk drive DAE AC power supply/cooling module
    Location
    Description
    Location
    Description
    AC power in (recessed plug) connector
    Power supply fault LED
    Cooling fault LED
    Part number label
    Power supply on LED
    Captive screw

    Review Table 12 for the LED descriptions and status meanings.

    Table 12. 3U 15 disk drive DAE AC power supply/cooling module LEDs
    LED
    Location
    Color
    State
    Description
    Cooling fault
    Amber
    On
    Fault, one or both blowers not operating normally
    Off
    No fault, blowers operating normally
    Power supply on
    Green
    On
    Power on
    Off
    Power off
    Power supply fault
    Amber
    On
    Fault
    Blinking
    During power shutdown and during overvoltage and undervoltage protection (OVP/UVP) fault
    Off
    No fault or power off

    General information on drawer-type DAEs

    Each DAE with internal drives typically consists of the following components:

    • Drive carrier
    • Disk drive
    • Link control cards (LCCs)
    • Power supply
    • Cooling modules
    • EMI shielding
    • Cable management arms
    Drive carrier

    The disk drive carriers are metal and plastic assemblies that provide smooth, reliable contact with the enclosure slot guides and midplane connectors. Each carrier has a handle with a latch and spring clips. The latch holds the disk drive in place to ensure proper connection with the midplane. Disk drive activity/fault LEDs are integrated into the carrier.

    Disk drives

    Each disk drive consists of one disk drive in a carrier. You can visually distinguish between disk drive types by their different latch and handle mechanisms and by type, capacity, and speed labels on each disk drive. You can add or remove a disk drive while the DAE is powered up, but you should exercise special care when removing disk drives while they are in use. Disk drives are extremely sensitive electronic components.

    Link control cards (LCCs)

    An LCC supports, controls, and monitors the DAE, and is the primary interconnect management element. Each LCC includes connectors for input and expansion to downstream devices. An enclosure address (EA) indicator and bus (loop) identification indicator is located on one LCC of each DAE.

    Power supply

    The power supplies and cooling modules or fans are separated. The power supplies are located on the rear. The power supply module has an orange knob used for removing and installing the power supply module from the DAE .

    Cooling modules (Fans)

    The cooling modules or fans are separate from the power supply modules. The cooling modules or fans are located on the front and middle of the drawer-type DAEs, depending on DAE type. The cooling modules or fans can only be installed/removed by sliding the DAE forward. You access the cooling modules or fans from inside the DAE.

    EMI shielding

    EMI compliance requires a properly installed electromagnetic interference (EMI) shield in front of the DAE disk drives. When installed in cabinets that include a front door, the DAE includes a simple EMI shield. Other installations require a front bezel that has a locking latch and integrated EMI shield. You must remove the bezel/shield to remove and install the disk drive modules.

    Cable management arms

    Locking Scissor-type cable management arms attach to the rear of the drawer-type DAEs to provide easy cable management for the power cords and SAS cables that attach to the rear ports of the DAE. The cable management arms extend to an open position when the unlocked DAE is pulled forward in the cabinet and retract to a closed position when the DAE is pushed back into the cabinet.

    3U, 80 (2.5-inch) DAE

    The 80 (2.5-inch) disk drive DAE is 3 rack units (U), 3.4 inches (8.64 cm) high, and includes slots for 80 2.5-inch disk drives. It uses a 12-Gb/s SAS interface for communication between the storage processors (SPs) and the DAE.

    Review the following sections for details on the components and LEDs comprising this DAE.

    3U, 80-drive DAE top view

    Component overview

    The 3U, 80-drive DAE includes the following internal components:

    • Disk drives in 2.5-inch carriers (hot-swappable) (1)
    • 10 redundant cooling modules
      • Five in the front of the system, labeled 0-4 (2)
      • Five at the rear of the system, labeled 5-9 (3)

    The disk drive slots and cooling modules on an 80-drive DAE are located inside the enclosure. To access the disk drives, release and pull the enclosure out of the cabinet. The enclosure slides out of the cabinet far enough for you to access its internal components, and then locks on the rails in the service position so that you cannot pull it out any farther.

    Figure 9. 3U, 80-drive DAE internal component locations (top view)
    An illustration of the top view of an 80-drive DAE. The system is fully populated with 80 drives and 10 fans. The drives are called out with the number 1. The five fans at the front are called out with the number two. The five fans at the rear are called out with the number three.
    Disk drive LEDs
    Figure 10. 2.5 inch disk drive LEDs
    The top view of a 2.5 inch disk drive. The two LEDs at the bottom are marked with a number. The bottom left LED is marked with a 1, and the bottom right LED is marked with a 2.
    LED
    Location
    Color
    State
    Description
    Disk drive on/activity
    1
    Blue
    On
    Powering and powered up
    Blinking
    Disk drive activity
    Disk drive fault
    Amber
    On
    Fault has occurred
    -
    Off
    No fault has occurred
    Cooling module LEDs

    Cooling modules contain only one LED, to indicate that the part has faulted.

    Figure 11. Cooling module fault LED location
    An illustration of a fan. At the bottom left of the fan, there is an orange LED that is enlarged for detail. This is the fault LED.

    3U, 80-drive DAE front view

    There is only one component accessible from the front of the 3U 80-drive DAE, the system status card (SSC).

    Figure 12. 3U 80-drive DAE system status card location
    The front of an 80-drive DAE. There is a number one near the system status card fault LED, a number two near the system status card power LED, and a number three near the system fault LED.
    Table 13. System status card status LEDs
    LED
    Location
    Color
    State
    Description
    System status card fault LED
    Amber
    On
    Fault within the system status card
    -
    Off
    No fault
    System fault LED
    Amber
    On
    Component within the system (disk, fan LCC, power supply) has faulted
    -
    Off
    No fault
    System status card power LED
    Blue
    On
    Powered on and no fault
    -
    Off
    Powered off

    3U, 80-drive DAE rear view

    The following components are accessible from the rear of the 3U, 80-drive DAE:

    • Two 12-Gb/s SAS link control cards (LCC); A () and B ()
    • Four power supplies ()

    The 3U, 80-drive DAE rear components are redundantly distributed across two sides, A and B. When viewed from behind, the right half of the system makes up the A-side of the DAE, and the left half of the system makes up the B-side.

    Figure 13. 3U, 80-drive DAE rear component locations
    The rear view of an 80-drive DAE. There is a number one to indicate LCC B (on the left side of the system, a number two to indicate LCC A (on the right side of the system) and a number three to indicate the four fans at the top of the system.

    3U, 80-drive DAE LCC

    Link control card functions and features

    The LCC supports, controls, and monitors the DAE, and is the primary interconnect management element. Each LCC includes connectors for input and output to downstream devices.

    The LCCs in a DAE connect to the storage processors and other DAEs. The cables connect the LCCs in a system in a daisy chain topology.

    Internally, each DAE LCC uses protocols to emulate a loop; it connects to the drives in its enclosure in a point-to-point fashion through a switch. The LCC independently receives and electrically terminates incoming signals. For traffic from the system's storage processors, the LCC switch passes the signal from the input port to the drive being accessed; the switch then forwards the drive output signal to the port.

    Each LCC has four ports marked AA/A and BB/B. The A and B ports are used when connecting (A) or expanding (B) using x4 lane cables. The AA/A and BB/B ports are both used when connecting (AA/A) or expanding (BB/B) using x8 lane cabling.

    Each LCC independently monitors the environmental status of the entire enclosure, using a microcomputer-controlled monitor program. The monitor communicates the status to the storage processor, which polls disk enclosure status. LCC firmware also controls the SAS Phys and the disk-module status LEDs.

    An enclosure ID, sometimes referred to as the enclosure address (EA), indicator is located on each LCC. Each LCC also includes a bus (back-end port) identification indicator. The SP initializes the bus ID when the operating system is loaded.

    Note:  Some LCCs may not have the enclosure ID display ( ) or back-end bus display ( ). These LCCs are functionally identical to LCCs with the enclosure ID display and back-end bus display. LCCs with displays always replace LCCs without displays.
    3U, 80-drive DAE LCC connectors and LEDs

    Each 3U, 80-drive DAE LCC contains the following ports, LEDs, and connectors:

    Figure 14. 12-Gb/s LCC ports, LEDs and connectors
    The rear view of an 80-drive DAE with various features highlighted.
    Table 14. 12-Gb/s LCC ports, LEDs and connectors
    Location
    Description
    12-Gb/s mini SAS ports
    Mini SAS port status LED
    Enclosure ID display a
    LCC fault LED
    LCC power LED
    Back-end (BE) bus ID display a
    LCC management port (RJ-12) (not used)
    a. May not be included on all LCCs.
    Table 15. 12 Gb/s LCC LEDs
    LED
    Location
    Color
    State
    Description
    Mini SAS port status LED
    Blue
    On
    SAS port linked up
    Green
    On
    Powered on
    -
    Off
    No connector in port
    LCC fault LED
    Amber
    On
    Fault within the LCC
    -
    Off
    No fault or powered off
    LCC power LED
    Green
    On
    Powered on and no fault
    -
    Off
    Powered off

    3U, 80-drive DAE power supply

    Power supply functions and features

    The power supplies are located above the LCCs.

    Each power supply is an auto-ranging, power-factor-corrected, multi-output, offline converter with its own line cord. Each supply supports a fully configured DAE and shares load currents with the other supply. The drives and LCCs have individual soft-start switches that protect the disk drives and LCCs if they are installed while the disk enclosure is powered up.

    Power supply components and LEDs
    Figure 15. 3U, 80-drive DAE power supply components and LEDs
    Table 16. 3U, 80-drive DAE power supply components and LEDs
    Location
    Description
    AC power in (recessed plug) connector
    Release lever
    Retaining bail
    Power supply fault LED
    AC output LED
    AC input LED
    Table 17. 3U, 80-drive DAE power supply LEDs
    LED
    Location
    Color
    State
    Description
    Power supply fault
    Amber
    On
    Fault
    -
    Off
    No fault or power off
    AC power LED (input)
    Green
    On
    Power on
    -
    Off
    Power off, verify source power
    AC output LED
    Green
    On
    Power on
    -
    Off
    Power off, verify source power