2014 SoCal VMware User Conference - vBrownBag TechTalk

1. Sept 24, 2014
Anthony Chow (@vCloudernBeer)

2.  A contemporary data center is a virtualized
data center:
 Server virtualization
 Storage virtualization
 Network virtualization
 A dynamic and agile environment.
 It increases demand for the network.
 Uses various solutions to alleviate the
increase demand for the network.

3. • Are these the solutions?
 Software Defined Networking (SDN)
 Network Function Virtualization (NFV)
 Network Virtualization (NV)
• IT vendor quick to claim to have a SDN solution.

4.  A framework
 Separation of control and data plane
 Commercial SDN Controllers:
 Cisco - Application Policy Infrastructure Controller
 HP - Virtual Application Networks (VAN) Controller
 NEC - ProgrammableFlow PF6800 Controller
 Nuage Networks - Virtualized Services Controller
 VMware - NSX Controller

5.  Closely related to SDN
 Network Services (Layer-4 to Layer-7)
Firewall
Load Balancer
VPN
IDS/IPS
 Run as virtual machine
 Dynamic network provisioning and
orchestration.
 Service chaining

6.  Network virtualization abstracts networking
from the physical network.
 Provides logical isolation on a physical
network
 Network Virtualization technologies:
 VLAN for Layer-2 networks
 VRF for Layer-3 networks
 Network Overlays

7.  One form of Network Virtualization
 Tunnels between end points are created on
existing physical networks (usually an IP
infrastructure).
 Using existing network infrastructure.
 Common Types of network overlay:
 Virtual Extensible LAN (VXAN)
 Network Virtualization using Generic Encapsulation
(NVGRE)
 Stateless Transport Tunneling (STT)
 Network Virtualization Overlay 3 (NVO3)

8.  Encapsulation
 VTEP
 VNI
 VTEP Gateway
 IP Multicast

13.  Virtual eXtensible Local Area Network
(VXLAN): A Framework for Overlaying
Virtualized Layer 2 Networks over Layer 3
Networks
 Problems VXLAN is designed to solve
 Limitations Imposed by Spanning Tree and VLAN Ranges
 Multi-tenant Environment
 Inadequate Table Sizes at ToR Switch

14.  RFC 7348 outlines the following rules for VXLAN:
 Each overlay is termed a VXLAN segment.
 Only VMs within the same VXLAN segment can communicate with each
other
 Each VXLAN segment is identified by a 24-bit segment ID (VNI).
 VNI identifies the scope of the inner MAC frame originated by the
individual VM
 VNI is an outer header that encapsulates the inner MAC frame
originated by the individual VM.
 VXLAN segment and VXLAN overlay network are interchangeable in the
RFC.
 VXLAN tunnels are stateless connection between 2 end points.
 Each end point is called a VXLAN Tunnel End Point (VTEP)
 VTEP can be implemented on a virtual switch, physical switch or physical
server either on hardware or software.
 Use of data plane learning.
 Multicast is used for carrying unknown destination, broadcast and
multicast frames (BUM traffic).
 VTEPs MUST NOT fragment VXLAN packets.