Cisco Nexus switches

The Cisco Nexus Series switches are modular and fixed port network switches designed for the data center. Cisco Systems introduced the Nexus Series of switches on January 28, 2008. The first chassis in the Nexus 7000 family is a 10-slot chassis with two supervisor engine slots and eight I/O module slots at the front, as well as five crossbar switch fabric modules at the rear. Beside the Nexus 7000 there are also other models in the Nexus range.

All switches in the Nexus range run the modular NX-OS firmware/operating system on the fabric. NX-OS has some high-availability features compared to the well-known Cisco IOS. This platform is optimized for high-density 10 Gigabit Ethernet.

The Nexus 7000 is the high-end model in the Nexus range of datacenter switches. Other models are:

The 1000v is a virtual switch for use in virtual environments including both VMware vSphere and Microsoft Hyper-V It is as such not a physical box but a software application that interacts with the hypervisor so you can virtualize the networking environment and be able to configure your system as if all virtual servers have connections to a physical switch and include the capabilities that a switch offers such as multiple VLANs per virtual interface, layer-3 options, security features etc. Per infrastructure/cluster you have one VM running the Nexus 1000v as virtual appliance, this is the VSM or Virtual Supervisor Module and then on each node you would have a 'client' or Virtual Ethernet Module (VEM) a vSwitch which replaces the standard vSwitch.

The VEM uses the vDS API, which was developed by VMware and Cisco together VMware announced in May 2017, vDS API support will be removed from vSphere 6.5 Update 2 and later. Therefore Nexus 1000v can no longer be used. VMware KB https://kb.vmware.com/s/article/2149722 https://www.theregister.co.uk/2017/03/31/vmware_to_end_support_for_thirdparty_virtual_switches/

Besides offering the NX-OS interface to configure, manage and monitor the virtual switch it also supports link aggregation where the standard virtual switches only support static LAGs

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