Build an iSCSI SAN with Drobo

Whether you are building an SAN for the first time, scaling out an application, or implementing a server virtualization cluster, Drobo provides sophisticated yet easy-to-use networked storage for your IT environment. Utilizing the industry-standard iSCSI protocol, Drobo connects to your existing TCP/IP Ethernet network to consolidate storage and centrally share it with your servers.

What is iSCSI?

iSCSI (pronounced "i-scuzzy") is an Internet Protocol (IP)-based storage networking standard for connecting storage arrays to computers, using high performance Ethernet. iSCSI is an industry-standard protocol, allowing organizations to consolidate and centralize storage while providing servers with the illusion of locally-attached disks. Unlike traditional Fibre Channel storage, which requires special-purpose cabling, iSCSI can be run over the existing Ethernet network infrastructure.

As Easy as USB for Windows and Mac

Drobo supports zero-click iSCSI connections on both Windows and Mac OS X. Once Drobo Dashboard is installed, access to the iSCSI storage over an Ethernet cable happens automatically. For Windows, Drobo Dashboard uses Microsoft's iSCSI software ("initiator"). As Mac OS X does not natively contain iSCSI support, Drobo Dashboard includes the necessary iSCSI software initiator for Mac OS X - free of charge.

iSCSI Deployment Scenarios

When building an iSCSI SAN with Drobo, there are a few network architectures you can use to ensure optimal performance and reliability for your applications. Remember that Drobo experts are available to you via daily Live Demo sessions: see a live demo of Drobo products, ask questions, and validate deployment ideas. Our experts cover configuration, sizing, network best practices, and infrastructure monitoring.

Drobo Direct-Attached to Servers

When deploying shared storage for the first time, you may only need to access the storage from two or three servers. If this is the case, you can directly connect Drobo to a Gigabit Ethernet port on a server. This is the easiest way to deploy an iSCSI Drobo. If your server is running Windows or Mac OS X, Drobo Dashboard will automatically configure the iSCSI settings, allowing iSCSI to be as easy as plugging in a USB drive.

Then, you can create volumes (or LUNs) on the Drobo and assign them to any of the attached servers. To a server, a volume will appear like a locally attached disk.

In a direct-attached setup, you can only provide storage to the number of available Ethernet connections on the Drobo. So for the B800i, it would be two servers, and for the B1200i it would be three servers. To share a Drobo with more servers, you will need to create a Storage Area Network (SAN).

Drobo Connected to Existing Network

If you need to share an iSCSI Drobo with more than two servers, you need to connect it to a network. Since iSCSI runs over a standard TCP/IP Ethernet network, you can connect Drobo to the same network you currently connect servers to. This architecture may be an easy and low cost way to connect Drobo to a file or backup server.

When you combine data and iSCSI storage traffic on the same network, you have to be aware of the added traffic load to ensure performance is still adequate. If you require high performance storage for business-critical applications like email and databases, it is highly recommended to create a dedicated network for iSCSI storage traffic.

Drobo Connected to a Dedicated Storage Area Network (SAN)

Common SAN design best practices call for a dedicated network for block storage traffic. This is to ensure proper performance, reliability, and security of the data that servers need to write and access. If block storage traffic is on the same network as email request, and a backup operation occurs, users may not be able to check email. Or, if a lot of email requests come in at the same time, a database may become very slow. When business-critical applications are using a Drobo, it is best to create a separate network for storage traffic.

A high-speed gigabit switch can be installed to handle iSCSI traffic. It will not be connected to the main company LAN to ensure optimal performance and keep storage traffic secure. The iSCSI ports on a Drobo will be connected to this switch. A server will have at least one Ethernet port connected to this switch, while other Ethernet ports will be connected to the LAN. This allows clients to access servers over the LAN and servers to access storage over the SAN. The SAN can then grow independently to scale the number of Drobos deployed, as well as the number of servers accessing them.

Learn More

Read more about BeyondRAID, Automated Data-Aware Tiering, Thin Provisioning and other Drobo technologies
that enable building a robust and reliable Drobo iSCSI SAN in RAID 25 Years Later: New Innovation in Storage.

Curious about how to configure Windows iSCSI Multipath I/O (MPIO) with Drobo iSCSI SAN? Click here to read the How-To Guide.