HP HP2-Z31 Online Practice Questions and Exam Preparation

HP HP2-Z31 Online Questions & Answers

• Question 51:

  Which protocol is used to discover directly connected links between OpenFlow devices?

  A. SNMP
  B. CDP
  C. OF-CONFIG
  D. LLDP
  D. LLDP

  ---

  LLDP is used to discover direct links between switches and BDDP is used to discover the switches in the same broadcast domain.

  Note: Using a link-discovery module, the controller generates both LLDP and broadcast packets (referred to as BDDPs) and sends them to all neighboring switches on a regular basis.

  Reference: OpenFlow Controller

• Question 52:

  Which command is a valid cURL command that can be executed against the HP VAN SDN Controller (assuming variables and scripts are configured correctly)?

  

  A. Option A
  B. Option B
  C. Option C
  D. Option D
  A. Option A

  ---

  Example: Install an Uploaded (STAGED) Application curl --noproxy --header X-Auth-Token: -ksS --fail --url https:// :/sdn/v2.0/apps//action/ -d install --request POST

  Incorrect Not B: incomplete command Not C: Use path /sdn/v2.0/... Not D: -H host header not specified. Reference: HP VAN SDN Controller Administrator Guide

• Question 53:

  Which table functionality was introduced with OpenFlow 1.3?

  A. ARP
  B. Metering
  C. Flow
  D. Matching
  B. Metering

  ---

  OpenFlow version 1.3 is the latest version of OpenFlow that has support from switch vendors. It is significantly different from OpenFlow version 1.0 (which was the previous version several vendors supported). Among others, the main features added since then are:

  1.1: Support for MPLS, Q-in-Q, VLANs, multipath, multiple tables, logical ports 1.2: Support for extensible headers (in match, packet_in, set_field), IPv6 1.3: Support for tunneling, per-flow traffic meters, Provider Backbone Bridging

  Reference: OpenFlow version 1.3 tutorial

• Question 54:

  How is a leader elected in an HP VAN SDN Controller team by default?

  A. by the lowest IP address value
  B. by the lowest priority value
  C. by the highest priority value
  D. by the highest IP address value
  C. by the highest priority value

  ---

  Once a team is configured, the configuration and monitoring of team members and their associated OpenFlow switches is performed by the team manager. If the team manager goes down, the controller with the next highest priority in the team configuration becomes the team manager. Note: Team Management Each controller belonging to a team is a team member. To centralize team management and control, one controller is designated as the team manager. Teaming is configured on one controller and is automatically propagated to the other controllers in the team, regardless of which controller becomes the team manager.

  Reference: HP VAN SDN Controller Administrator Guide

• Question 55:

  Spanning Tree Protocol is disabled on a network edge port. The port is assigned to a VLAN, which is a member of an aggregate OpenFlow 1.0 instance. What is the default behavior of all ingress traffic when no flow entry exists?

  A. Only SDN classified traffic is forwarded to the SDN Controller.
  B. All traffic is discarded.
  C. All traffic is forwarded to the egress port to the final destination address.
  D. All traffic is forwarded to the SDN Controller.
  B. All traffic is discarded.

  ---

  Flowchart detailing packet flow through an OpenFlow switch.

  

  Reference: OpenFlow Switch Specification Version 1.3.1

• Question 56:

  Two HP OpenFlow switches are connected to an intermediate layer 2 switch running LLDP, but not OpenFlow. This intermediate switch is configured with a single VLAN. Which protocol is used by the OpenFlow switches to discover this multi-hop link?

  A. CDP
  B. ND
  C. LLDP
  D. BDDP
  D. BDDP

  ---

  The LLDP messages allow the link service to discover that there is physical link between two switches. If the LLDP message on one side of the link (Packet_Out) is received on the other side of the link (Packet_In) by a switch, LS knows that the two switches are connected to each other. The service is also responsible for identifying multi-hop links. These are links where non- OpenFlow devices are connected between two OpenFlow switches and thus separate the OpenFlow switches. The Link Service does this by sending BDDP (Broadcast version of LLDP) messages in addition to LLDP messages. LLDP is a one hop protocol and may be consumed by a non-OpenFlow switch because LLDP uses a multicast address which the intermediate switch may have subscribed to the LLDP multicast. However, a broadcast frame (BDDP) will be forwarded typically by the intermediate switch. BDDP has the same TLV information as LLDP.

  Reference: HP SDN Network Services Modules

• Question 57:

  Refer to exhibit.

  

  Which HP VAN SDN Controller interface can a network administrator use to troubleshoot the southbound interface of the controller and displays the output shown in the exhibit?

  A. Audit Log
  B. OpenFlow Monitor
  C. OpenFlow Tracer
  D. Dissector
  C. OpenFlow Tracer

  ---

  The OpenFlow Tracer is a built-in packet sniffer similar to Wireshark.

  Incorrect:

  Not Openflow Monitor:

  

• Question 58:

  Which mechanism provides authentication of API calls via the REST API within the HP VAN SDN Controller?

  A. Openstack Keystone
  B. Java
  C. RabbitMQ
  D. Openstack
  A. Openstack Keystone

  ---

  The SDN controller uses Openstack Keystone as an identity management for managing users, generating tokens, as well as token validation. Reference: HP VAN SDN Controller Administrator Guide

• Question 59:

  An administrator wants to secure the connection between an HP Provision switch and HP VAN SDN Controller. What is the recommended approach to securing the OpenFlow messages?

  A. Use CA-signed certificates on an HP VAN SDN Controller and the HP Provision switches, and then use TLS to secure communication.
  B. Use OpenFlow message type 5 on the auxiliary channel to secure OpenFlow messages.
  C. Use an IPsec VPN between the HP Provision switch and the HP VAN SDN Controller to secure OpenFlow messages.
  D. Use self-signed certificates on an HP VAN SDN Controller and the HP Provision switches, and then use TLS to secure communication.
  A. Use CA-signed certificates on an HP VAN SDN Controller and the HP Provision switches, and then use TLS to secure communication.

  ---

  The Openflow controller component relies on PKI to establish mutual trust (2-way SSL) between itself and the Openflow switches that it manages. Please note that both the Controller and Device certificates must be signed by the same CA, so that the TLS connection will be established. Reference: HP VAN SDN Controller Administrator Guide

• Question 60:

  A customer writes an internal application that does not run properly and crashes. Which component of the HP VAN SDN Controller framework offers protection so that other applications continue to function?

  A. OSGi
  B. Zookeeper
  C. Cassandra
  D. Keystone
  A. OSGi

  ---

  Note:

  The OSGi specification describes a modular system and a service platform for the Java programming language that implements a complete and dynamic component model, something that does not exist in standalone Java/VM environments.

  Applications or components, coming in the form of bundles for deployment, can be remotely installed, started, stopped, updated, and uninstalled without requiring a reboot; management of Java packages/classes is specified in great detail.

  Application life cycle management is implemented via APIs that allow for remote downloading of management policies. The service registry allows bundles to detect the addition of new services, or the removal of services, and adapt

  accordingly.

  Incorrect:

  Not Zookeeper: ZooKeeper is a centralized service for maintaining configuration information, naming, providing distributed synchronization, and providing group services. Not Cassandra: Apache Cassandra is an open source distributed

  database management system designed to handle large amounts of data across many commodity servers, providing high availability with no single point of failure. Not Keystone: The SDN controller uses Openstack Keystone as an identity

  management for managing users, generating tokens, as well as token validation.