Virtualization and Datacenters

Question 1

Hypervisor

Answer 1

• Manages virtual environment and interaction of computer hardware and network

Question 2

Host (Guest OS)

Answer 2

• Hypervisor is installed onto a host operating system

Question 3

Bare Metal

Answer 3

• Type 1 Hypervisor is installed directly onto computer without going through OS

Question 4

vNIC

Answer 4

Virtual NIC

- Functions exactly like physical NIC on VM

Question 5

SAN

Answer 5

Storage Area Network

• Provisions access to storage devioces at block level
• Only accessed by servers running databases or applications that need shared storage

Question 6

iSCSI

Answer 6

Internet Small computer system interface

• Can be used to link SANs
• Is an alternative to Fibre Channel
• IP tunneling protocol that enables transfer of SCISI data over IP-based network.

Question 7

North South Traffic

Answer 7

• Flowing to and from datacenter

- Clients making requests and getting responses

Question 8

East West Traffic

Answer 8

• Traffic between servers within datacenter

Question 9

Overlay Network

Answer 9

• Used to implement point to point logical links between nodes or networks
• Abstracts physical topology to facilitate security of east-west traffic

Question 10

SDN

Answer 10

Software Defined Network

• Used to provision server instances and networks with automation and orchestration
• Inserts control layer between application and infrastructure layer

Question 11

Spine and Leaf

Answer 11

• Topology that supports use of SDN and overlay networks
• Spine layer is backbone of top tier switches, not linked to each other
• Leaf layer contains access switches, connected to every spine switch in full mesh

Question 12

ToR

Answer 12

• Used for Leaf access layer

- Support higher bandwidth than ordinary switches

Question 13

GRE

Answer 13

Generic Routing Encapsulation

- encapsulates data from layer 2 and layer 3 for tunneling over transport network

Question 14

mGRE

Answer 14

Multipoint GRE

• Supports point-multipoint links
• Like hub and spoke dynamic multipoint VPNs
• Used to connect branch offices to on premises data center at head office

Question 15

MPLS

Answer 15

Multiprotocol Lable Switching

• Means of creating private links with guaranteed service levels
• Uses Shim header instead rather than layer 3 header
• Traffic is isolated from any other customer or public traffic

Question 16

Fibre Channel

Answer 16

• Definted in T11 ANSI Standard
• Does not need to use fiber cabling
• Uses special hardware: Inititator, Target and Fc switch
• Highly redundant, but expenseive

Question 17

Fibre Channel over Ethernet

Answer 17

• Means of delivering fiber channel packets over ethernet cabling and switched
• Uses special 10/40/100gb adapters call converged network adapters
• Uses special frame type 0x8096
• Does nt quite run over standard ethernet and needs QoS mechanisms to ensure delivery

Question 18

SDN Application Layer

Answer 18

• Applies business loginc to make decisions on how traffic should be prioritized and secured
• Defines segmentation, ACLs and policing/shaping

Question 19

SDN Infrastructure Layer

Answer 19

• Devices (physical or virtual) that handle forwarding of traffic and imposition of ACLS and other security configurations

Question 20

SDN Control Layer

Answer 20

• Inserted between Application and Infrastructure Layer
• Implemented by SDN Controller
• Application layer gives southbound API and Infrastructure give northbound API
• Control plane and management plane sit at this level