unit 5 will go over cloud infrastructure and resource ... · powervc is the ibm virtualization...

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Unit 5 will go over cloud infrastructure and resource service models.

Unit 5: Cloud infrastructure and resource services models

LearnQuest Learning Library Content


Take a look at this Units learning objectives.




Most of you are cloud service users already. You search for services that can fulfill your work. You narrow down to a service that fits your need. Obviously, that service has to be listed somewhere in at least a cloud service catalog out there. The value of a service provider is in making different services available. A service requires careful design and implementation before listing.



Information Technology (IT) is depending heavily on automation. Anyone can find so many reasons for automation to make works easier. All those reasons are still valid in cloud service. However, “self-service” is the one ultimate objective in the cloud. If it is not self-service, it does not work with the cloud.




Cloud service is designed around these three principles:

• Each service is unique

• Cloud service user is different

• Cloud service application user interface is mandatory

You might find practical examples for these principles when working in cloud service design. The visual lists some of the examples to start thinking about.




At the most basic level, virtualization manager software understands the three main components of the infrastructure: compute, storage, and network. Recognizing these existing resources in your environment is the initial step in setting up the cloud. The virtualization manager then provides the facility for working with those resources. These working functions vary depending on the level of the software.




Kimchi is an open source virtualization manager that runs on a single local host. In this class environment, the host is a PowerKVM bare metal server. Kimchi provides a simple web user interface. In the visual, you see the toolbar across the top of the Kimchi web page. The infrastructure component menus on the toolbar are Host, Storage, and Network. Also presented on the toolbar are menus for Guests or virtual machines, Templates for defining virtual machines, and Administration for system management tasks.




PowerVC is the IBM Virtualization Center that manages virtual machines (VM) on Power servers. The home page presents the three familiar infrastructure components: Hosts, Storage (providers), and Networks. Virtual images and virtual machines are presented as icons in the left panel. PowerVC also provides similar managing functions like in Kimchi. Between these two virtualization managers, the differences are in the hypervisor they work with.




Hypervisor is the firmware that works directly with the bare metal server to divide and allocate resources such as processors and memory. Virtualization manager retrieves those resources from the hypervisor and turns them into virtual resources. Virtualization manager depends on the hypervisor to work with specific hardware. The visual shows a comparison between Kimchi and PowerVC. Kimchi works with the PowerKVM hypervisor one at a time. PowerVC works with Hardware Management Console (HMC) which runs the PowerVM hypervisor. Since HMC can manage multiple Power bare metal servers, PowerVM works with multiple servers. Therefore, PowerVC works with multiple Power bare metal servers.




This slide lists basic functionalities of a virtualization manager, which works with the hypervisor to manage virtual resources from physical resources. Virtualization manager makes resources consumable in the virtualization environment. Virtual machines are the consumers of these resources. Every virtual machine has a lifecycle that starts from a template, an image, to a virtual machine instance. The instance runs with many operations throughout its lifecycle until it shuts down.




Kimchi uses a template for specifying resources for creating a virtual machine. Using a template to define resource attributes is common in virtualization. A template has a unique name. The CDROM is where the ISO image comes from. The image can also come from a file system dir. The Vendor and Version information is retrieved from the image. When the virtual machine is starting up, the messages are displayed in graphical user interface like VNC or text console. Storage Pool provides space for the image installation. This attribute and the rest can be modified or selected:

• Number of CPUs or processors

• Amount of memory (in MB units)

• Disk space (in GB units)

Last but not least is the network selection.




Creating images from scratch is not a critical function of a virtualization manager. Where do images come from? Some software tools specialize in building images. Pre-built images can be imported from local file like an ISO file or a CDROM or downloaded from remote servers. It is critical that the virtualization manager supports the image file format. Kimchi limits support to the ISO format. PowerVC can use other image formats. Most important, all these formats have to be compatible with the Power or PPC binary format.




What kinds of operations does a virtual machine instance potentially go through? The visual shows the Actions drop-down menu on a guest in Kimchi. The actions are: Connect, Manage Media, Edit, Reset, Shut Down, Power Off, and Delete. Actions like Delete, Power Off, Shut Down, or Reset are destructive and should be invoked with care. The Edit action is to modify some of the virtual machine attributes. Usually these attributes can be changed only while the virtual machine is power off.




Graphical user interface (GUI) like Kimchi is simple and easy to use. However, it is limited and requires a GUI like VNC. An alternative is to use the command line interface (cli) like virsh, for virtual shell. Virsh and other tools together make up command interfaces for the virtualization manager. It is common in virtualization software that the command-line commands are wrappers of the application programming interface (API). The Kimchi GUI uses this cli or API to communicate with PowerKVM. The visual shows examples of the virsh commands that can be run in PowerKVM host.




The virsh help command lists all commands to run with virsh. Be sure to know what a command does before executing it. Some of the commands are destructive. However, the list commands are useful for exploring system resources. Try grep to display only the virsh help for list commands.




The key difference between private and public cloud is that of the capability of controlling hardware infrastructures. Private cloud is in an exclusive environment where its administrators, owners, or users have full controls of the physical infrastructures. In a public cloud, users depend mostly on the cloud service provider. Users in a public cloud should also be aware that they might share data storages or compute resources with other users. The cloud service model defines: public, private, or hybrid cloud.




Building a hybrid cloud from scratch is hard. But, it can be built from the two existing components: a public cloud and a private cloud. A hybrid cloud is a solution that tunnels limited access from public cloud to private cloud environment when needed. Tunneling is an implementing method. In reality, the access connection is like a draw bridge. Security is the utmost concern for public cloud.





Please review these important keywords from this unit.




Some additional keywords.




Write your answers here:

1.

2.

3.




How did you do?




Please review the three items for you upcoming lab experience.




At this time you should be able to:

• Identify the model of cloud services

• Recognize the cloud consumable resource concepts

• Understand the hybrid cloud channeling between systems

• Apply the Infrastructure as a Service concept in the lab environment



unit 5 will go over cloud infrastructure and resource ... · powervc is the ibm virtualization...

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