Long a purveyor of server solutions, Dell is branching out into the world of network switching. With the brand-new Dell PowerConnect 6024, the company is leaping from their previous layer 2 edge switches to the centre of the network: layer 3 core switching.
Stepping into the core switch market — even the fixed-port, nonchassis-based market — is a bold move. As I mentioned in review of the PowerConnect 3300 series switches, Dell joined the edge-switching fray hoping to up-sell server buyers into low-cost 10/100Mb layer 2 switches.
With the introduction of Dell’s core switch, however, it’s a new ballgame. A core switch is the heart of any infrastructure and needs to be bulletproof. So there’s more at stake than cost — it’s a matter of trust. After all, if you can’t depend on the core, you can’t depend on any part of the infrastructure.
Does Dell succeed with the 6024? Let’s examine the scorecard. Redundant, hot-swappable power supplies? Check. Redundant, hot-swappable case fans? Check. VRRP (Virtual Router Redundancy Protocol) support, 802.1q trunking, and LACP (Link Aggregation Control Protocol)?
Check, check, and check. In fact, the 6024 has just about every major feature of the competing fixed-port, layer 3 switches priced hundreds or thousands of dollars higher.
Port proliferation
The 6024 is a true layer 3, fixed-port core switch, with 24 GbE ports available in two configurations. Both configurations offer 24 full gigabit ports, with eight of those ports available in fibre or copper. The fibre flavour has 24 SFP (Small Form-factor Pluggable) ports and eight copper gigabit ports, with only 24 total ports usable at a time. The copper flavour has 24 copper gigabit ports and eight SFP ports, with the same use limits.
In both configurations, the 6024 actually appears to have 32 physical ports, with the last eight overlapping ports 16 to 24. These options are refreshing in a fixed-port core switch. It can act as an aggregation switch with the potential to handle 16 fibre trunks to edge switches, eight servers, 16 servers, and eight fibre trunks — or any other combination within its physical limitations.
The 6024 has a 35.6mps forwarding rate, support for as many as 4096 VLANs, OSPF, RIP (Routing Information Protocol), as well as DVMRP (Distance Vector Multicast Routing Protocol), IGMP (Internet Group Multicast Protocol), and the aforementioned VRRP. Full-spanning tree support is present, including RST (Rapid Spanning Tree) support, facilitating rapid recovery from link and switch failure.
Layer 4 ACLs (access control lists) are available. ACLs can be bound to a physical port, aggregate port, or to a VLAN interface; but an ACL can only be bound to the input traffic on an interface. The QoS configuration is somewhat limited, supporting only eight priority queues, but it’s relatively simple to configure traffic class, IP port, and DSCP (Differentiated Services Code Point) CoS (class of service) mappings.
Support for a discovery protocol, à la Cisco Systems’ CDP (Cisco Discovery Protocol), is starkly lacking. Without support for CDP or its soon-to-be-official derivative, LLDP (Link Layer Discovery Protocol), every Dell switch in a network is blind to the presence of other switches. This lack primarily affects network administration, but having discovery protocol support would also make management easier. Dell is planning on supporting LLDP (802.1ab) with a firmware upgrade once the protocol is released.
The 6024’s CLI (command-line interface) is billed as “Cisco-like”, and it does closely resemble Cisco’s IOS (Internetwork Operating System).
But some commands do not mirror IOS exactly. For instance, “conf t”, shorthand for configure terminal, isn’t a valid command on the 6024, whereas “conf” will achieve the same result. The “wr mem” command isn’t available at all, but “copy run start” works.
These syntax differences can be a benefit or a curse for administrators. Moving between Cisco and Dell CLIs in a mixed environment can be frustrating, but the conceptual similarities to Cisco’s IOS ease the learning curve.
Configuring VLANs in the 6024, however, is easy: Create a VLAN by number, assign an IP address to the VLAN interface, and assign a port to that VLAN. Trunking to other switches via 802.1q is equally simple.
Another of the 6024’s bonus features is a true out-of-band 10/100Mb management port, just underneath the nine-pin serial console port, permitting a truly dedicated management network.
The 6024 also has a built-in cable tester, accessed using the CLI or Web interface, that can quickly test a cable plugged into any port on the switch for length and faults as long as the port isn’t linked. It’s not crucial but it’s handy for troubleshooting.
The management edge
I put the 6024 through its paces, starting with raw throughput tests and progressing through QoS and ACL performance tests. The 6024 performed admirably through it all. I was able to push data at wire-rate from any interface to any other, within a VLAN or across VLANS, and with or without an ACL on the physical port or VLAN interface.
Actual file copy rates generally eclipsed 70MBs from server to server via FTP and HTTP over Cat6 copper patch cables, and raw TCP throughput held steady at roughly 960Mbs through all my tests.
The switch’s Web interface is responsive and straightforward, albeit somewhat clunky to navigate. Still, it’s an improvement over the Web interface of the Dell 3300 switches, with increases in speed and fluidity.
The 6024’s real edge, though, comes in switch management.
As with the 3300 series, the 6024 is bundled with OpenManage Network Manager, a plug-in to Dell’s OpenManage framework that permits simple, GUI network administration for Dell switches. This tool lets network administrators push configuration changes to many switches at once, view the network topology, archive configurations, and more.
Because it neatly handles so many management tasks, Network Manager will be invaluable to admins charged with the care and maintenance of a medium to large LAN infrastructure.
Other vendors offer this functionality, but generally at a substantially higher cost. Dell offers Network Manager free with the 6024, and has a $US4995 Advanced Edition option that permits advanced VLAN, ACL, and QoS management. For most implementations, these capabilities aren’t immediately necessary, but it’s nice to have the option.
After running it through my testing gauntlet, the 6024 comes out as a high-performance, high-availability layer 3 core switch at a great price. There are still some missing pieces, however. The DHCP forwarding option is currently a global parameter and can’t be configured per VLAN. There is no discovery protocol, and I found the ASCII configuration file cluttered. It also doesn’t show default configuration commands like Cisco’s IOS.
Dell has challenges ahead, especially with proven competition in the fixed-configuration core switch market from Cisco, Nortel Networks, and 3Com. As with any new entry on the core network hardware scene, the 6024 will have to prove itself in the real world. Based on its lab performance, it will do well.