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Cabling Your RAID Enclosure

Dell™ PowerVault™ MD3000 RAID Enclosure Hardware Owner's Manual

  Before You Begin

  About the Enclosure Connections

  Cabling the Enclosure

  Attaching MD1000 Expansion Enclosures


This section provides the following information:


Before You Begin

Before connecting your RAID enclosure, ensure that the following are available:


About the Enclosure Connections

The RAID array enclosure is connected to a host via two hot-pluggable RAID controller modules. The RAID controller modules are identified as RAID controller module 0 and RAID controller module 1 (see Figure 1-4).

Each RAID controller module has at least one SAS In port connector that provides the direct connection to the host or node. A second SAS In port connector is available on the optional dual-port RAID controller. SAS In port connectors are labeled In-0 and, if using the optional controller, In-1(see Figure 1-5).

NOTE: When you cable from a host server to an MD3000 SAS In port connector, either Out port of the server's HBA can be used.

Each MD3000 RAID controller module also contains a SAS Out port connector. This port allows you the option to connect the RAID enclosure to an expansion enclosure.


Cabling the Enclosure

You can cable your enclosure to up to four hosts and up to two expansion enclosures. The configuration that you choose depends on the number of hosts you have, whether you are connecting to a standalone host or a cluster node, and the level of data redundancy that you need.

The figures that follow are grouped according to the number of SAS In port connectors available on the MD3000. Single SAS In port configurations and dual SAS In port configurations each support redundant and nonredundant cabling.

Redundancy vs. Nonredundancy

Nonredundant configurations, configurations that provide only a single data path from a host to the RAID enclosure, are recommended only for non-critical data storage. Path failure from a failed or removed cable, a failed host bus adapter, or a failed or removed RAID controller module results in loss of host access to storage on the RAID enclosure.

Redundancy is established by installing separate data paths between the host and the storage array, in which each path is to different RAID controller modules. Redundancy protects the host from losing access to data in the event of path failure, because both RAID controllers can access all the disks in the storage array.

Single SAS In-Port Configurations

Figure 2-1 through Figure 2-5 show supported nonredundant and redundant cabling configurations to MD3000 RAID controller modules with a single SAS In port connector. Each diagram shows the maximum number of optional expansion enclosures attached.

Figure 2-1 through Figure 2-3 show one and two hosts, each connected to only one RAID controller module that is subsequently expanded to two more storage enclosures. The hosts can share storage space but without redundant paths, if one path were to fail, the server on that path would be disconnected from the storage array.

Figure 2-1. Cabling One Host with Nonredundant Data Paths

Figure 2-2. Cabling Two Hosts with Nonredundant Data Paths

Figure 2-3. Cabling a Two-Node Cluster (Single HBA, Nonredundant Data Paths from Each Node)

Figure 2-4 and Figure 2-5 show redundant, high-availability cabling configurations for one and two hosts. If any one path fails, at least one HBA is still connected to one RAID controller.

Figure 2-4. Cabling a Single Host (Dual HBA with Two Cable Connections) Using Redundant Data Paths

Figure 2-5. Cabling a Single Host (Single-HBA) Using Redundant Data Paths

Dual SAS In-Port Configurations

Figure 2-6 through Figure 2-12 show supported nonredundant and redundant cabling configurations to MD3000 RAID controller modules with two SAS In port connectors. Each diagram shows the maximum number of optional expansion enclosures attached.

Figure 2-6 shows how one, two, three, and four hosts can each be connected to a RAID controller module nonredundantly. The RAID controller module is subsequently expanded to two more storage enclosures. The hosts can share storage space but without redundant paths, if one path were to fail, the server on that path would be disconnected from the storage array.

Figure 2-6. Cabling Up to Four Hosts with Nonredundant Data Paths

Figure 2-7 through Figure 2-10 show redundant, high-availability cabling configurations for one and two hosts. If any one path fails, at least one HBA is still connected to one RAID controller.

Figure 2-7. Cabling a Single Host (Dual HBA with Four Cable Connections) Using Redundant Data Paths

Figure 2-8. Cabling a Single Host (Single HBA) Using Redundant Data Paths

Figure 2-9. Cabling Two Hosts (with Dual HBAs) Using Redundant Data Paths

Figure 2-10. Cabling Two Hosts (with Single HBAs) Using Redundant Data Paths

Figure 2-11 through Figure 2-12 show redundant, two-node cluster configurations using a single RAID enclosure that is subsequently expanded to two more storage enclosures.

Figure 2-11. Cabling a Two-Node Cluster (Single HBA, Redundant Data Paths from Each Node)

Figure 2-12. Cabling a Two-Node Cluster (Dual HBA, Redundant Data Paths from Each Node)

For a more detailed discussion of redundancy and nonredundancy, as well as alternate path software, see "Hardware Redundancy and Failover".


Attaching MD1000 Expansion Enclosures

One of the features of the MD3000 is the ability to add up to two MD1000 expansion enclosures for additional capacity. This expansion increases the maximum physical disk pool to 45 3.5" SAS physical disks.

As described in the following sections, you can expand with either a new MD1000 or an MD1000 that has been previously configured in a direct-attach solution with a PERC 5/E system.

NOTICE: Ensure that all MD1000 expansion enclosures being connected to the MD3000 are updated to the latest Dell MD1000 EMM Firmware from support.dell.com. Dell MD1000 EMM Firmware version A00 is not supported in an MD3000 array; attaching an MD1000 with unsupported firmware causes an uncertified condition to exist on the array. See the following procedure for more information.

Expanding with Previously Configured MD1000 Enclosures

Use this procedure if your MD1000 is currently directly attached to and configured on a Dell PERC 5/E system. Data from virtual disks created on a PERC 5 SAS controller cannot be directly migrated to an MD3000 or to an MD1000 expansion enclosure connected to an MD3000.

NOTICE: If an MD1000 that was previously attached to PERC 5 SAS controller is used as an expansion enclosure to an MD3000, the physical disks of the MD1000 enclosure will be reinitialized and data will be lost. All MD1000 data must be backed up before attempting the expansion.

Perform the following steps to attach previously configured MD1000 expansion enclosures to the MD3000:

  1. Back up all data on the MD1000 enclosure(s).

  2. While the enclosure is still attached to the PERC 5 controller, upgrade the MD1000 firmware to an A03 or higher configuration. Windows systems users can reference the DUP.exe package; for Linux kernels, users can reference the DUP.bin package.

  3. Before adding the MD1000 enclosure(s), make sure the MD3000 software is installed and up to date. For more information, refer to the Dell PowerVault Compatibility Matrix available on support.dell.com.

    1. Install or update the SAS driver and firmware. For Windows systems users, use the update package. For Linux systems users, use the DKMS package.

    1. Install or update (to the latest version available on support.dell.com) the MD Storage Manager on each host server. Refer to the PowerVault MD3000 Installation Guide for detailed information.

    2. Install or update (to the latest version available on support.dell.com) the multipath drivers on each host server. The multipath drivers are bundled with Modular Disk Storage Management install. On Windows systems, the drivers are automatically installed when a Full or Host selection is made.

    3. Using the MD Storage Manager, update the MD3000 RAID controller firmware to the latest version available on support.dell.com (Support® Download Firmware® Download RAID Controller Module Firmware) and the NVSRAM (Support® Download Firmware® Download RAID Controller Module NVSRAM).

  4. Stop I/O and turn off all systems:

    1. Stop all I/O activity to the array and turn off affected host systems attached to the MD3000.

    1. Turn off the MD3000.

    2. Turn off any MD1000 enclosures in the affected system.

  5. Referencing the applicable configuration for your rack (Figure 2-1 through Figure 2-12), cable the MD1000 enclosure(s) to the MD3000.

  6. Turn on attached units:

    1. Turn on the MD1000 expansion enclosure(s). Wait for the expansion status LED to light blue.

    1. Turn on the MD3000 and wait for the status LED to indicate that the unit is ready:

      • If the status LEDs light a solid amber, the MD3000 is still coming online.

      • If the status LEDs are blinking amber, there is an error that can be viewed using the MD Storage Manager.

      • If the status LEDs light a solid blue, the MD3000 is ready.

    2. After the MD3000 is online and ready, turn on any attached host systems.

  7. After the MD1000 is configured as the expansion enclosure to the MD3000, restore the data that was backed up in step 1.

After they are online, the MD1000 enclosures are available for use within the MD3000 system.

Expanding with New MD1000 Enclosures

Perform the following steps to attach new MD1000 expansion enclosures to the MD3000:

  1. Before adding the MD1000 enclosure(s), make sure the MD3000 software is installed and up to date. For more information, refer to the Dell PowerVault Compatibility Matrix available on support.dell.com.

    1. Install or update the SAS driver and firmware. For Windows systems users, use the update package. For Linux systems users, use the DKMS package.

    1. Install or update (to the latest version available on support.dell.com) the MD Storage Manager on each host server. Refer to the PowerVault MD3000 Installation Guide for detailed information.

    2. Install or update (to the latest version available on support.dell.com) the multipath drivers on each host server. The multipath drivers are bundled with Modular Disk Storage Management install. On Windows systems, the drivers are automatically installed when a Full or Host selection is made.

    3. Using the MD Storage Manager, update the MD3000 RAID controller firmware (Support® Download Firmware® Download RAID Controller Module Firmware) and the NVSRAM (Support® Download Firmware® Download RAID Controller Module NVSRAM).

  2. Stop I/O and turn off all systems:

    1. Stop all I/O activity to the array and turn off affected host systems attached to the MD3000.

    1. Turn off the MD3000.

    2. Turn off any MD1000 enclosures in the affected system.

  3. Referencing the applicable configuration for your rack (Figure 2-1 through Figure 2-12), cable the MD1000 enclosure(s) to the MD3000.

  4. Turn on attached units:

    1. Turn on the MD1000 expansion enclosure(s). Wait for the expansion status LED to light blue.

    1. Turn on the MD3000 and wait for the status LED to indicate that the unit is ready:

      • If the status LEDs light a solid amber, the MD3000 is still coming online.

      • If the status LEDs are blinking amber, there is an error that can be viewed using the MD Storage Manager.

      • If the status LEDs light a solid blue, the MD3000 is ready.

    2. After the MD3000 is online and ready, turn on any attached host systems.

  5. Using the MD Storage Manager, update all attached MD1000 firmware:

    1. Select Support® Download Firmware® Download Environmental (EMM) Card Firmware.

    1. Check the Select All check box so that all attached MD1000 enclosures are updated at the same time (each takes approximately 8 minutes to update).


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