Chapter 44 - Cloud Architecture Flashcards
1
Q
What are the characteristics of a Cloud Computing service?
A
- Can be requested on demand - The consumer can action changes as required without requiring interaction with the provider
- Can dynamically scale (it is elastic) at will so it appears to the consumer as if the resources are unlimited
- Uses a pool of resources, rather than dedicated specific servers to specific customers, and dynamically allocates resources from that pool for each customer request
- Has a variety of network access options - Can be accessed from multiple different network options (e.g. Private WAN, Internet, MPLS VPN)
- Can be measured and billed back to the customer based on the amount used
2
Q
What is a KVM?
A
- Keyboard, Video Display, Mouse
- Normally a server could be characterised as no KVM since they are administered remotely
3
Q
What is Cisco’s range of Blade devices called?
A
- UCS B series (Unified Computing System Blade series)
- UCS is their server range
4
Q
What is a VM?
A
- Virtual Machine
- A virtual instance of an OS hosted on a server
- Multiple can be hosted on a single server instead of dedicating one hardware server to each instance
5
Q
What is Multithreading?
A
- The ability for a CPU core to run multiple tasks at once
6
Q
What is a Hypervisor?
A
- Also known as a VMM (Virtual Machine Monitor)
- Manages and allocates hardware resources to VMs based on their settings
7
Q
What is the relationship between a vSwitch and vNICs?
A
- A vSwitch is a virtual device that allows a network to form between vNICs
- Neither of these are physical devices
- Normally there is a vNIC per VM but there may only be 1 or 2 physical NICs
8
Q
What are ToR and EoR switches?
A
- Top of Rack - Found in a data centre, this would be a switch that sits at the top of a rack and acts similarly to an Access switch. It allows the rest of the devices in the rack to connect to the rest of the data centre LAN. Normally the devices in the rack connect to two ToR switches for redundancy
- End of Row - Found in a data centre, this would be a switch that sits at the end of a row of racks and acts similarly to a Distribution switch. It connects all of the Top of Rack switches together and to the rest of the data centre LAN. Normally the ToR switches connect to two EoR switches for redundancy
9
Q
Key points about virtualisation in data centres
A
- The OS is decoupled from the hardware it runs on so that the OS as a VM can run on any other server in the data centre that has enough resources
- The virtualisation software can automatically start and move VMs between servers in the data centre
- Data centre networking includes vSwitches and vNICs within each server
- Data centre networking can be programmsed by the virtualisation software allowing new VMs to be configured, started, moved, and stopped, with the network details being configured automatically
10
Q
What are other names for Private Cloud and Public Cloud?
A
- Private Cloud - On-Premise (Although it may not be on-premises)
- Public Cloud - Cloud
11
Q
What is a Private Cloud service?
A
- A cloud service created and utilised by a single company. It may be created by a different company for this company.
- May be on or off premises
12
Q
What is a Public Cloud service?
A
- A cloud service created and administered by a single company and then provided to other companies
13
Q
What is Infrastructure as a Service?
A
- Also called IaaS
- A consumer pays for the use of a VM hosted on a cloud provider’s hardware. The consumer specifies the resources dedicated to the VM and the Operating System
- Well known examples could be Amazon EC2 and Google Compute Engine
14
Q
What are other terms for “Starting a VM?
A
- “Spinning up a VM”
- “Instantiating a VM”
15
Q
What is Software as a Service?
A
- Also called SaaS
- A consumer pays for a bit of software that runs on a VM or multiple VMs. The consumer has no input over the details or resources of the VM(s).
- Well known examples could be iCloud, Google Drive, Dropbox, etc.
