Cisco Systems, Inc. is upgrading software on its Catalyst 6500 switches to enable individual processes on the devices to run separately, allowing customers to reboot processes without taking the entire switch offline.
“For example, you’ll have TCP running in a different memory space than routing, which will be in a different memory space than FTP,” said Joh Yen, senior manager in the switching product marketing group for Cisco. “The benefit is you get better fault containment. If you have a process fault in UDP, that’s not going to affect your routing process.”
This shift to discrete modular processes, says Cisco, makes for simpler software upgrades to subsystems of the switch that support processes such as TCP, User Datagram Protocol (UDP), routing and FTP.
The new software architecture was also designed to cut the time it takes to check software upgrades such as patches or new features, Cisco added.
Because such upgrades can be accomplished via alterations to individual processes, rather than to the entire image of Cisco’s IOS software, customers need to do less testing to determine if upgraded processes will disrupt other functions. Upgrades can be done to the routing module, for instance, while the switch is in use without dropping a packet.
With the Catalyst 6500 software upgrade comes the automation of routine maintenance tasks, improved diagnostics and simpler resolution of network problems, in conjunction with another new software feature: Embedded Event Manager (EEM).
Because EEM detects more details about the switches’ subsystems than SNMP does, it can automatically respond to more minor problems based on policies set by customers. If a given process eats up more CPU capacity than the policy allows, for example, EEM can trigger a response. EEM can take any action that can be initiated via Cisco’s standard command line interface.
Yen said: “If a predictive process is faulty, for example, an IT administrator could create a policy that says, if that process happens I want the switch to restart the process, take a snapshot of what was going on in the box at the time, generate those diagnostics and then e-mail that to me.”
Running processes independently on switches is common in carrier-grade gear, but is not so widespread in business-class network equipment, says Mark Fabbi, a vice-president at Gartner. Juniper has been the notable exception, he says, as the JunOS software in its enterprise switches hails from the company’s carrier-grade switches and routers.
Cisco’s software upgrade is a big change, Fabbi says.
“Before this, IOS was monolithic,” he said. “If you want to patch one tiny thing, it’s an IOS upgrade.”
The upgraded offering could have an impact on network security as well, Fabbi says. Customers might be more likely to install Cisco patches sooner because it should be easier to do and the patches won’t have the potential broad impact on other subsystems.
“People are reluctant to dabble with IOS as a whole,” said Fabbi.
The new software features for Catalyst 6500 switches are scheduled to be available in the fourth quarter for switches using Cisco’s Supervisor Engine 720 and in the first quarter of next year for switches using Supervisor Engine 32. There is no extra fee for customers with a SMARTnet maintenance contract.