Overview

Virtual Topologies

CSIT VPP functional tests are executed in VM-based virtual topologies created on demand using VIRL simulation platform contributed by Cisco. VIRL runs on physical baremetal servers hosted by LF FD.io project. Based on the packet path thru SUT VMs, two distinct logical topology types are used for VPP DUT data plane testing:

  1. vNIC-to-vNIC switching topologies.
  2. Nested-VM service switching topologies.

vNIC-to-vNIC Switching

The simplest virtual topology for software data plane application like VPP is vNIC-to-vNIC switching. Tested virtual topologies for 2-Node and 3-Node testbeds are shown in figures below.

virtual-2n-nic2nic
virtual-3n-nic2nic

SUT1 and SUT2 are two VMs (running Ubuntu or Centos, depending on the test suite), TG is a Traffic Generator (running Ubuntu VM). SUTs run VPP SW application in Linux user-mode as a Device Under Test (DUT) within the VM. TG runs Scapy SW application as a packet Traffic Generator. Network connectivity between SUTs and to TG is provided using virtual NICs and VMs’ virtio drivers.

Virtual testbeds are created on-demand whenever a verification job is started (e.g. triggered by the gerrit patch submission) and destroyed upon completion of all functional tests. Each node is a Virtual Machine and each connection that is drawn on the diagram is available for use in any test case. During the test execution, all nodes are reachable thru the Management network connected to every node via dedicated virtual NICs and virtual links (not shown above for clarity).

Nested-VM Service Switching

Nested-VM (Virtual Machine) service switching topology test cases require VPP DUT to communicate with nested-VM(s) over vhost-user virtual interfaces. Nested-VM(s) is(are) created on SUT1 and/or SUT2 for the duration of these particular test cases only. Virtual test topology with nested-VM(s) is shown in the figure below.

virtual-3n-vm-vhost

Functional Tests Coverage

CSIT-1908.1 includes following VPP functionality tested in virtual VM environment:

Functionality Description
LISP Locator/ID Separation Protocol overlay tunnels and locator/id mapping control.

Functional Tests Naming

CSIT-1908.1 follows a common structured naming convention for all performance and system functional tests, introduced in CSIT-17.01.

The naming should be intuitive for majority of the tests. Complete description of CSIT test naming convention is provided on Test Naming.