Cisco Catalyst OS with optional Cisco IOS Software on the MSFC provides Layer 2/3/4 functionality for the Cisco Catalyst 6500 by integrating two operating systems. A switch running the Cisco Catalyst OS only on the supervisor engine is a Layer 2 forwarding device with Layer 2/3/4 functionality for quality of service (QoS), security, multicast, and network management, but does not have any routing capabilities. Layer 3 routing functionality is provided by a Cisco IOS Software image on the MSFC routing engine (optional in the Cisco Catalyst 6500 Series Supervisor Engine 1A and Cisco Catalyst 6500 Series Supervisor Engine 2 and integrated within Cisco Catalyst 6500 Supervisor Engine 32 and Cisco Catalyst 6500 Series Supervisor Engine 720 models). The two operating systems work together to provide complete Layer 2/3/4 system functionality.
The hybrid model operates based on two operating images, two configurations, and two command lines; one each for Cisco Catalyst OS and Cisco IOS Software. The default operation of Cisco Catalyst OS is as a switch (all ports bridging in VLAN1). Additionally, the switch-running hybrid can be configured to operate as a router.
Cisco IOS Software for the supervisor engine on the Cisco Catalyst 6500 Series provides a single Cisco IOS Software image, configuration, and command line to support all Layer 2, 3, and 4 functionality on the switch. Cisco IOS Software has historically been a Layer 3 operating system on routing platforms, and when installed on the supervisor engine of a Cisco Catalyst 6500 has expanded these capabilities to include true Layer 2 functionality as well. Cisco IOS Software requires an MSFC daughter card be present on the supervisor engine (default on the Cisco Catalyst 6500 Supervisor Engine 32 and Cisco Catalyst 6500 Series Supervisor Engine 720).
The default operation of Cisco IOS Software is as a router (all ports are Layer 3 and in the shutdown state), but the interfaces can also be configured to operate as a switch.
The native Cisco IOS Software operating model was originally developed to target service provider and enterprise data center backbones and distribution layer services. However, with the SXF and SXH Cisco IOS Software trains, many wiring closet features have been added. Cisco IOS Software combines the switching features of the Cisco Catalyst 6500 Series with routing features of Cisco IOS Software to create a single, integrated operating system that performs all switching and routing functionality, providing operational ease of use. A Cisco IOS Software system has the capability to scale the throughput and bandwidth of a Cisco Catalyst 6500 Series to 400+ Mpps and 720 Gbps, respectively.
The following example demonstrates the creation of vlan 8 in the Cisco Catalyst OS and Cisco IOS Software:
Cisco Catalyst OS | Cisco IOS Software |
CatOS(enable) set vlan 8 | IOS#configure terminal IOS(config)#vlan 8 IOS(config-vlan)#exit |
For more details click Comparison of the Cisco Catalyst and Cisco IOS Operating Systems for the Cisco Catalyst 6500 Series Switch
