Cisco Cisco Prime Virtual Network Analysis Module (vNAM) 6.1 Libro bianco
3-23
Cisco Virtualized Multiservice Data Center (VMDC) Virtual Services Architecture (VSA) 1.0
Design Guide
Chapter 3 VMDC VSA 1.0 Design Details
Services
Figure 3-14
Sample vWAAS Application Reports
Traffic must be redirected from networking devices to the vWAAS for optimization; there are multiple
ways to do so, including policy based routing and Web Cache Coordination Protocol (WCCP). In this
system we focused on validation of AppNav redirection from the CSR.
ways to do so, including policy based routing and Web Cache Coordination Protocol (WCCP). In this
system we focused on validation of AppNav redirection from the CSR.
Introduced on CSR in IOS XE 3.8, AppNav provides key benefits over previous technologies such as
WCCP, providing a way to scale traffic redirection and improve performance and lower CPU overhead
using the following characteristics and techniques:
WCCP, providing a way to scale traffic redirection and improve performance and lower CPU overhead
using the following characteristics and techniques:
•
Scaling redirection through decoupling flow distribution from flow processing; in AppNav
deployments, a flow distribution unit, called the AppNav Controller, and multiple service nodes
(1-32) process flows. In VMDC VSA 1.0, CSR functions as an AppNav Controller, and vWAAS
functions as a service node. As noted, code prerequisites are IOS-XE 3.8 (CSR) and 5.1 (vWAAS).
deployments, a flow distribution unit, called the AppNav Controller, and multiple service nodes
(1-32) process flows. In VMDC VSA 1.0, CSR functions as an AppNav Controller, and vWAAS
functions as a service node. As noted, code prerequisites are IOS-XE 3.8 (CSR) and 5.1 (vWAAS).
•
Intelligent redirection of new flows based on the load on each service node.
•
Bypass of flows that do not require optimization; service nodes can inform the AppNav Controller
to directly pass through non-optimized traffic, minimizing latency and resource utilization.
to directly pass through non-optimized traffic, minimizing latency and resource utilization.
•
Ability to add or remove a service node with minimal impact to traffic.
•
For special applications (for example, Messaging API (MAPI)/Exchange and Citrix VDI), ensures
that a family of flows is redirected to the same service node for optimal treatment.
that a family of flows is redirected to the same service node for optimal treatment.
vPath redirection from the Nexus 1000v DVS is another option. In this case interception and redirection
is based on the Nexus 1000V port-profile configuration. This is a MAC-in-MAC redirection technique,
which requires vWAAS to be L2-adjacent to the host toward which traffic is destined (it need not be
located on the same ESXi host). In this case, vPath interception is configured, on the port profile of the
VM server in both directions, to redirect VM server packets to vWAAS. vPath redirects are transported
over the Nexus 1000V service VLAN. vWAAS receives the vPath intercepted packet, performs WAN
optimization, and returns the response packet to VEM. vWAAS egress traffic received by VEM is
forwarded without additional vPath interception. Management packets are not vPath-encapsulated. The
key benefits of vPATH interception are:
is based on the Nexus 1000V port-profile configuration. This is a MAC-in-MAC redirection technique,
which requires vWAAS to be L2-adjacent to the host toward which traffic is destined (it need not be
located on the same ESXi host). In this case, vPath interception is configured, on the port profile of the
VM server in both directions, to redirect VM server packets to vWAAS. vPath redirects are transported
over the Nexus 1000V service VLAN. vWAAS receives the vPath intercepted packet, performs WAN
optimization, and returns the response packet to VEM. vWAAS egress traffic received by VEM is
forwarded without additional vPath interception. Management packets are not vPath-encapsulated. The
key benefits of vPATH interception are:
•
No need to define the direction of interception (in or out)—vPath maintains a flow entry table for
each TCP flow that is used to intercept and redirect traffic.
each TCP flow that is used to intercept and redirect traffic.