Showing posts from 2014

How VXLANs Work

TIP: An Ethernet Ethertype of 0x0800 indicates that the payload is an IP. TIP: The maximum transmission unit (MTU) requirement for VXLAN is minimum of 1,600 bytes to support IPv4 and IPv6 guest traffic. TIP: The VLAN tag in the layer 2 Ethernet frame exists if the port group that your VXLAN VMkernel port is connected to has an associated VLAN number. When the port group is associated with a VLAN number, the port group tags the VXLAN frame with that VLAN number.
VXLAN (Virtual Extensible LAN) is an Overlay between the ESXi hosts, and it´s an Ethernet in IP overlay technology, where the original layer 2 frames are encapsulated in a User Datagram Protocol (UDP port 4789) packet and delivered over a transport network. It gives the capability to create a proper micro-segmentation, and it doesn’t have the number limitation as VLANs do. VXLAN uses the VXLAN encapsulation, so VLAN configuration becomes irrelevant. VXLAN modes are Unicast, Hybrid and Multicast (this refers to the Control Traffic)…

VMware NSX Fundamentals

In July 2012 VMware acquired Nicira (Nicira was founded by Martin Casado of Stanford University and it had a product called NVP - Network Virtualization Platform), and that’s basically how VMware started the NSX Venture and got into the SDN. NSX enables you to start with your existing network and server hardware in the data center, as it´s independent of the network hardware. This does not mean that you can use just any hardware; you still to have a stable, Highly Available and Fast network. ESXi hosts, virtual switches, and distributed switches run on the hardware. 

On the other hand, to avoid the Physical Network problem, tend towards Life and Spine architecture.

Nowadays you wont find many clients with the Spine and Leaf network deployed. Therefore maybe the best approach would be proposing a slow transition (Upgrade even) where the traditional 3-Tier Architecture would be evolving towards the below presented L3 Spine and Leaf:

There are 2 versions of NSX: -NSXv, or NSC for vSphere (yo…

How vSphere sees VLANs