Basically a small blade-server chassis, Dell's PowerEdge VRTX packs up to four server blades and as many as 32 small-form-factor disk drives into a self-contained, cluster-in-a-box solution. From a cost and convenience perspective, the cluster in a box is compelling for a wide range of use cases. It's an ideal hardware setup for virtualizing a branch office infrastructure or even certain small to medium-size enterprise workloads.
The PowerEdge VRTX has the horsepower to handle workloads like Microsoft Exchange and the storage space for a large Microsoft SharePoint deployment. The secret sauce is in the Series-8 Shared PowerEdge RAID Controller (PERC) that handles the sharing of storage among all of the blades in the chassis. Internally, the VRTX supports a variety of I/O fabric interfaces including 10GbE, though the current switch only supports 1Gb speeds. An integrated gigabit switch with eight external ports on the rear of the chassis can be used for connecting external Ethernet devices.
My review unit came equipped with two Dell M620 blades each containing two Intel Xeon E5-2650 CPUs and 96GB of memory. You could pack up to 768GB into the 24 DIMM slots inside the M620, if needed. The VRTX chassis will function in either an upright tower configuration or in a standard 19-inch, 5U rack mount. It supports the M620 or M520 blade servers, or a mix of both. Storage options include 12 full-sized drives in lieu of the small-form-factor drives.
Redundancy is a foundational design principle in the VRTX, and you see it everywhere. Four independent power supplies rated at 1,050W support multiple modes, including 2+2 for AC redundancy and 3+1, 2+1, and 1+1 for power supply redundancy. The minimum number of power supplies required will depend on the load out of the system and total power requirements. For cooling, the standard configuration includes six hot-pluggable redundant fan modules and four rear-mounted blower modules. Surprisingly, despite all of this cooling hardware, this system is superquiet.
Setup and configuration
The first thing you notice when looking at the front of the VRTX is the small LCD and navigation pad. This control panel allows you to change configuration settings such as the management IP addresses for the Chassis Management Controller (CMC) and the individual blades. With these management IP addresses configured, you can then complete the rest of the configuration remotely.
USB and video ports located on the front of the system allow for local configuration using a keyboard, mouse, and monitor. These ports act as a KVM (keyboard, video, and mouse) switch to any of the four blade slots. The LCD navigation pad includes an option to select a specific blade module to connect to the KVM. You won't need a special adapter as the connector on the front panel accepts a standard VGA cable.
Dell provides a wealth of information to help you configure the VRTX for most any operating environment. A number of steps are required to configure both the storage and networking to fully support a clustered system. The Web interface to the CMC provides the means to configure all components of the system either manually or via user-friendly wizards.
The first step is to configure storage. Here you'll see a warning for the Multiple Assignment mode, which allows virtual disks to be assigned to multiple virtual adapters: "Do not use this mode unless the servers have cluster services installed on them." That's because all disk I/O originates from the host operating system and must be handled in a cluster-aware fashion to prevent data corruption. If that OS is Windows Server 2012, you must manually edit the Windows registry on each node in order for the cluster service to see drives connected to the Shared PERC8 controller. Dell has an entry in its Tech Center Wiki documenting this process. VMware vSphere 5.1 works out of the box with the same hardware in a clustered configuration.
Managing the blades and chassis
Dell has been delivering out-of-band management capabilities as a part of its server product line for a long time. In fact, the Integrated Dell Remote Access Controller (iDRAC) is up to version 7 in the latest line of servers, including the M620 blade installed in the VRTX I reviewed.
The Chassis Management Controller provides access to all system-level components (storage, switch, PCIe slots, power supplies) and presents a good overview of system health. You can also launch individual component management tools from the CMC, including a remote console to the server blades. The remote console uses either a native plug-in based on ActiveX or a Java-based one. You'll need to perform a few configuration steps in Internet Explorer to get the native plug-in to work. That's because IE ships with fairly tight security settings to minimize any potential threats. All required steps are fully documented in the iDRAC7 user's guide. The remote console app includes the ability to connect remote media such as an ISO file for operating system installation purposes.
You manage the individual blades through the iDRAC Web interface. You can launch this GUI directly from the CMC interface or by entering the IP address into the address bar of your favorite Web browser. From iDRAC you have full control of the server blade right down to powering the system on or off. Here again the use of colors, such as showing the power threshold in yellow, help an administrator quickly identify any problems with the system. You'll also find a graphical display of temperature readings and an export tool to collect power and temperature data for reporting purposes.
There's not much you can't do with the combination of Dell's CMC and iDRAC, short of actually pulling the power cord. About the only complaint one might make is that the remote console application is sluggish. Although that's more of a comment on Internet Explorer and Java than the application itself, other remote console tools (such as HP's iLO and Remote Desktop) are more responsive.