Dell PowerConnect 6248 a perfectly priced performer

Dell's new networking switch packs 10G at just $1,500 a port

Switches are the umpires of the IT field: They’re either invisible, or they’re in trouble. Nothing less than 100 percent reliability is acceptable.

It’s with this mind-set that I unboxed the new Dell PowerConnect 6248, the next generation of the top-end PowerConnect 6024, which offers Gigabit Ethernet ports as well as Layer-3 core switching functions. The 6248 differs from the 6024 in many ways — the least of which is a full complement of 48 Gigabit Ethernet ports.

The 6024 was Dell’s first L3 switch, and it came in two flavors, a 24-port copper or 24-port SFP fiber model, each having four dual-personality copper/fiber ports. At the back of the 6024 were two standard power supplies.

The 6248 boasts the same four dual-personality ports up front, but it lacks the second power supply in back. The likely reason for the single power supply: The 6248 has two module slots in the rear. These slots can house either a 48Gbps stacking module, or a 10-Gig module containing two 10-Gig ports.

Thus, a fully loaded 6248 can drive a total of four 10-Gig ports in addition to the 48 gigabit ports up front. Stock, the price is $2,649. With a single 10-Gig module and two XFP LR optics, it climbs to $5,546. By contrast, a Cisco 4948 10-Gig switch with the same configuration costs more than $15,000 — and the 6248 can add two more 10-Gig ports than the 4948 can.

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So what’s the catch? Performance on the front 48 gigabit ports is wire-rate, and, according to Dell, the 10-Gig performance is also wire-rate. Although my lab wasn’t equipped to do a full 10GbE test, my Neterion 10-Gig LR cards could only push about 3Gb through the 6248. This is likely due to the fact that the 10-Gig cards aren’t in 266MHz PCI-E slots, although Dell has acknowledged rate issues with 10G NICs. Some tweaking of interface parameters helped here, but the switch still didn’t hit true 10-Gig performance.

On the management side, Dell has delivered many features lacking in previous versions of the PowerConnect OS. Loopback interfaces are present. The file system has seen some updates, including the ability to add descriptions to firmware images. Dell also has souped up the SNMP functions significantly; the switch supports SNMP v1, v2, and v3, plus it delivers notification filters.

Also finally available is LLDP (Link-Layer Discovery Protocol), or 802.1ab, which permits LLDP-compliant switches to find each other on a network, à la CDP (Cisco Discovery Protocol).

Dell also has updated the CLI, which now sports a command-completion feature. Not only does it recognize partial unique commands, but it completes the command for you without the customary Tab key. It’s a nice feature, but takes some getting used to. Otherwise, the CLI remains an exercise in Cisco-style IOS with a few unique features.

Compared with the 6024, the 6248 is much easier to drive. The configuration-file syntax is far better; the 6024 seemed to arbitrarily scatter commands around within the file. The 6248 groups them together, so all commands pertaining to a single Ethernet port can be found under that port’s header.

On the Web UI front, little has changed in terms of design and layout, but the problems with non-Microsoft browsers don’t seem to be present. Earlier revisions of the Web UI for Dell PowerConnect switches would, at best, warn that the browser might not be compatible, or, at worst, completely prevent access.

For my tests, I replaced the Cisco switches in my lab with the 6248 and an older 6024 switch. The initial configuration was very simple, and the network hasn’t exhibited any problems under normal day-to-day operation. I have encountered a few small problems, such as the inability to configure DHCP forwarding to more than one DHCP server.

Although I can’t attest to the 6248’s reliability for more than 30 days, I can safely say that, given its performance in that time, it’s a solid switch at an incredible price.

InfoWorld Scorecard
Configuration (20.0%)
Scalability (20.0%)
Management (20.0%)
Value (10.0%)
Performance (30.0%)
Overall Score (100%)
Dell PowerConnect 6248 8.0 9.0 8.0 10.0 8.0 8.4