Download Designing Cisco Data Center Infrastructure.test-king.300-160.2019-10-16.1e.267q.vcex

Reference: http://www.cisco.com/c/en/us/td/docs/unified_computing/ucs/sw/gui/config/guide/2-2/b_UCSM_GUI_Configuration_Guide_2_2/configuring_upstream_disjoint_layer_2_networks.pdf

When server virtualization is implemented, the edge of the network is pushed from the traditional location in the network access layer, implemented in physical switches, to the virtual network access layer that is implemented in software in the server hypervisor. The Cisco Nexus 1000V Switch is an intelligent virtual network access layer switch that runs Cisco NX-OS Software, Cisco's data center operating system that runs on all Cisco data center products. Operating inside the Microsoft Hyper-V hypervisor, the Cisco Nexus 1000V supports Cisco Virtual Network Link (VN-Link) server virtualization technology to provide:  
✑ 
Policy-based virtual machine connectivity  
✑ Mobile virtual machine security and network policy  
✑ Nondisruptive operating model for your server virtualization and networking teams When server virtualization is implemented in the data center, servers and virtual machines are not managed the same way as physical servers. Server virtualization is treated as a special deployment, leading to longer deployment time, with more coordination needed among server, network, storage, and security administrators. With the Cisco Nexus 1000V, you have a consistent networking feature set and configuration and provisioning model for both the physical and the virtual networks. Virtual machine networks can use the same network configuration, security policy, diagnostic tools, and operating models as physical server deployments that are connected to physical switches. This unified approach provides faster deployment and troubleshooting and makes the administration of virtualization environments essentially the same as for nonvirtualized deployments.  Developed in close collaboration with Microsoft, the Cisco Nexus 1000V Switch is certified by Microsoft and integrates with Microsoft Windows Server and Microsoft System Center Virtual Machine Manager (SCVMM). You can use the Cisco Nexus 1000V to manage your virtual machine connectivity with confidence in the integrity of the server virtualization infrastructure.   
Cisco Nexus 1000V Switch Components   
Cisco Nexus 1000V Switches have two main components:  
✑ Virtual supervisor module (VSM)  
✑ Virtual Ethernet module (VEM)  
The VSM provides the switch control and management plane, and the VEM provides the data plane for the switch (Figure 1). The VSM can run as a virtual machine on any Microsoft Hyper-V host or as a virtual service node on the Cisco Nexus 1010 and 1110. The VEM runs as a plug-in (extension) to the Microsoft Hyper-V switch in the hypervisor kernel, providing switching between virtual machines.   
Cisco Nexus 1000V sees the VSMs and VEMs as modules. In the current release, a single VSM can manage up to 64 VEMs. The VSMs are always associated with slot numbers 1 and 2 in the virtual chassis. The VEMs are sequentially assigned to slots 3 through 66 based on the order in which their respective hosts were added to the Cisco Nexus 1000V Switch.

Product Architecture  
The Cisco Nexus 1000V Series Switch has two major components (Figure 1): the virtual Ethernet module (VEM), which runs inside the hypervisor, and the virtual supervisor module (VSM), which manages the VEMs. 
Virtual Supervisor Module  
The Cisco Nexus 1000V Series VSM controls multiple VEMs as one logical modular distributed virtual switch. Configuration is performed through the VSM and is automatically propagated to the VEMs.  
Reference: https://www.cisco.com/c/en/us/products/collateral/switches/nexus-1000v-switch-vmware-vsphere/data_sheet_c78-492971.html

A graceful restart, or nonstop forwarding (NSF), allows OSPFv2 to remain in the data forwarding path through a process restart. When OSPFv2 needs to perform a graceful restart, it sends a link-local opaque (type 9) LSA, called a grace LSA. 
Reference: https://networklessons.com/cisco/ccie-routing-switching-written/ospf-graceful-restart/

Reference:
http://www.cisco.com/en/US/products/ps5989/products_configuration_guide_chapter09186a0080664e20.html