Forfusion's IT Expert Compares Cisco Nexus and Catalyst

An Engineer’s perspective:

Earlier I talked about some of the very high level differences between Cisco Nexus (NX-OS) and Catalyst (IOS) switching, and I provided an overview on some of the main NX-OS specific features.

This post is the first of a five part blog series which will consist of easily digestible overviews and some practical configuration (config) examples.

All of the information in this blog series can be found on the Cisco DocsWiki, which is a great resource for both Cisco NX-OS and IOS.

For this example I will use the Cisco Nexus 7000 and Cisco Catalyst 6500 to draw a direct comparison. In this engineer’s opinion, they are the most similar out of the two ranges. In fact, before the Cisco Nexus 7000 was first brought to market, the Cisco Catalyst 6500 series typically fulfilled its role (that of core and aggregation switches) in the Data Centre space.

Before I go into the key differences between the default configurations, I’ll outline two biggest differences (in my opinion):

Interfaces are labelled in the configuration as Ethernet. There aren’t any speed designations. A user can execute show commands in configuration mode without using the do command in IOS. The following three tables outline some of the specific differences.

Table 1: Initial system setup

Table 2: Default configuration differences related to interface types and configuration parameters

Table 3: Key differences related to L2 switching features and protocols.

In the next blog post, we'll will explore L3 features and protocols.