There is little consensus regarding what constitutes a "critical" network link in the enterprise. But if a gigabit-link outage means loss of revenue or potential loss of life or property, that connection would be considered critical by anyone's standards. Shore Microsystems' new SM-2601F Gigabit Link Protector can provide the automatic redundant-link failover your devices need to stay connected despite network problems.
Two Paths To Take
Murphy's Law guarantees when network trouble comes to visit, it will affect your most important devices at the worst possible time. Shore's SM-2601F offers your critical resources, such as servers and routers, the benefit of two gigabit paths to the network: an active primary path, and a backup secondary path that will take over within an instant of a primary link failure. This means high reliability is possible at the physical layer, with the SM-2601F offering defense against the effects of cable cuts, misbehaving NICs and switch ports, errant disconnects and other network maladies that can take down your prized gigabit platform. With a growing number of lights-out sites and shrinking staffing levels as IT budgets continue to strain, the SM-2601F can provide an extra set of hands when it's needed most.
The SM-2601F stands guard between a server or protected switch/server combination and a router or switch. It offers the added benefit of management-forced switchover to the secondary path to allow for maintenance on the primary link's devices. If the switch that feeds your critical server on the primary link needs maintenance, you can force the SM-2601F to activate the backup link, which will then connect the server to another switch. The transition should be swift enough at the rated 30-ms failover speed that most of the protected server's network applications won't skip a beat, and the desired tasks can be carried out on your now-offline router. Want even more protection? Run the redundant leg to a completely different switch.
You can order industry-standard LX (long haul) or SX (short haul) fiber interfaces as dictated by your topology, but fixed LC jacks are your only option for network connectivity. The protected server/router can use LC fiber or an RJ-45 gigabit port, and management is done through a simple 10-Mbps RJ-45 connection. A standard DB-9 console port, an alarm contact jack, well-thought-out indicators and a few control buttons round out the SM-2601F's user controls. A redundant power supply is available for greater reliability.
Simple Interface
Setup of the SM-2601F begins with console connection or BOOTP dynamic assignment of an IP address. There is no GUI, but the same staff members that work the network routers would likely configure this device, so the command-line approach should be easy. You can enable or turn off telnet service to the box for security and accomplish the overall device setup in minutes if you know your desired configuration before you fire up the unit.
Good
• Small footprint
• Reliable link failover
• Alarms on failure
Bad
• Only LC jacks available
• Network-management port
• Mbps only
Vendor Info
SM-2601F Gigabit Fiber Link Protector, $2,965 (SX version). Shore Microsystems, (800) 600-9656. www.shoremicro.com
For my tests, I connected my protected server through the SM-2601F version SX to two Cisco Systems Catalyst 3524 switches on GBIC ports. I had some odd negotiation problems between one of the switch ports and the SM-2601F, but a bit of switch configuration smoothed it out. The failover process worked as advertised--when I tampered with the primary connection, the backup took over without skipping a beat. I manipulated the physical connection and disabled the switch port in management to induce failover, and the panel alarms and SNMP trap notification went out as expected. After several dozen forced failovers, the only strange result was a single instance of slow link acquisition between the SM-2601F and the switch, but I couldn't duplicate it. Every other time, the primary link took over seamlessly.
Two SM-2601F units can occupy a single rack unit and ensure redundant connectivity. The look of the SM-2601F is understated, with simple push buttons on its face and basic command-line and standard MIB controls that offer pretty neat protection. Automatic failover, local and remote control, failure reporting and configuration flexibility make the SM-2601F worth a look for your important gigabit links.
Lee Badman is a network engineer at Syracuse University. Write to him at lhbadman@syr.edu.
REPORTS
Analyize In-Line NAC strategies and products.
ANALYTICS Plan and design your enterprise blade server deployments
InformationWeek U.S. IT Salary Survey 2008
Salaries for business technology professionals are falling. Here's what you need to know in order to make good hiring decisions and personal career choices. Download Today
REPORTS
ANALYTICS
Follow 
