When a RAID Controller Module Is Replaced or Removed

Figure 3-3. Two Hosts, each with Two Cable Connections

dual-HBA host server

RAID controller module 0

RAID controller module 1

MD3000 RAID Enclosure

This cabling topology, when used with alternate path software, ensures a redundant path from the host to the virtual disks. If any component (HBA, HBA port, cable, RAID controller module port, or RAID controller module) fails, a host can still access the virtual disks through an alternate path.

NOTE: This configuration is the most redundant for two hosts directly connected to a single RAID enclosure.

When a RAID Controller Module Is Replaced or Removed

When one RAID controller module fails, or is removed from the RAID enclosure, failover software on the host directs the alternate RAID controller module to assume all controller responsibilities for the storage array. The virtual disks owned by the failed or removed RAID controller module are failed over to the surviving controller and no data is lost.

NOTE: For Linux kernels, stop and then restart the SMagent after moving a controller offline, replacing a controller, or removing SAS cables from (or attaching SAS cables to) Red Hat® Enterprise Linux® (version 4), SUSE Linux Enterprise Server 9 (x86_64), or SUSE Linux Enterprise Server 10 (x86_64) host servers.

Because host-based multi-path software is configured for automatic failback, the data paths and virtual disks are restored to their original RAID controller module after the RAID controller module is replaced.

Automatic failback occurs under the following conditions:

•Data is protected by dual redundant paths to the host.

•The host has multi-path failover software installed, and it is configured for auto failback.

•Failover occurred due to either RAID controller module lockdown, replacement, or path failover.

NOTE: Clustering requires simultaneous access from cluster nodes to shared storage. If you have clustering software installed on the host, automatic failback should be disabled to prevent "ping-pong" with single-path failure. For more information on clustering, a link to clustering documentation is included on the MD3000 Resource CD under Product Documentation.

For more information on failover, see "Cabling the Enclosure" on page 22.

Using Your RAID Enclosure

MD3000 specifications

The Dell MD3000 is a renowned storage area network (SAN) solution recognized for its flexibility, scalability, and high performance. Designed to meet the demands of small to medium-sized businesses (SMBs) and enterprise environments, the MD3000 offers a plethora of features that enhance data management and storage capabilities.

One of the standout features of the MD3000 is its modular design. This allows users to start with a basic configuration and expand their storage capacity as their needs grow. The system can support up to 30 drives, including both SATA and SAS drives, giving users the ability to optimize cost and performance based on their specific requirements. With support for a diverse range of drive types, the MD3000 ensures that businesses can implement a storage solution that aligns perfectly with their performance and budgetary needs.

The MD3000 leverages advanced technologies to deliver exceptional performance and reliability. It is equipped with Intelligent Disk Pools that optimize the allocation of data across drives, ensuring improved access speeds and overall system efficiency. This dynamic management of data not only enhances performance but also extends the lifespan of the storage devices.

Data protection is another critical component of the MD3000. The system features various RAID configurations, allowing users to choose the level of redundancy that suits their operational requirements. Additionally, robust snapshot capabilities help businesses create point-in-time copies of their data, enabling quick recovery in case of data loss or corruption.

Connectivity options are abundant with the MD3000. It supports both iSCSI and Fibre Channel, providing users the flexibility to integrate it seamlessly into existing network infrastructures. This adaptability makes it an attractive option for organizations looking to modernize their storage systems without overhauling their entire architecture.

Furthermore, the MD3000 is equipped with a user-friendly management interface. The GUI enables quick provisioning and monitoring of storage resources while providing insightful analytics and alerts, allowing IT teams to maintain optimal performance with ease.

In summary, the Dell MD3000 is a highly versatile and efficient storage solution that meets diverse organizational needs. Its scalable architecture, advanced features, and strong support for data protection and management make it an ideal choice for businesses aiming to enhance their storage capabilities while ensuring reliability and performance. Whether for virtualization, database management, or general storage needs, the MD3000 stands out as an excellent investment in enterprise storage technology.