Control Layer Flashcards
What is Control Layer?
Includes software tools that are responsible for managing and controlling the underlying cloud infrastructure and enables provisioning of IT resources for creating cloud services
What are the Key functions of the control layer?
Resource configuration, resource provisioning, and monitoring resources. Also receives request from the service and orchestration layers
What is Control Software?
Ties together the underlying resources and works in conjunction with virtualization software to enable: resource pooling, dynamic allocation of resources and optimizing utilization.
What are the two types of control software?
Element Manager & Unified Manager
what does Element Manager do?
Enables to perform initial component configurations and allows to modify it : installing guest OS, configuring zoning, security settings, VLANS, RAID, and LUN masking
allows to expand resource capacity
Enables to identify the problem and performs troubleshooting
Monitors the infrastructure component for performance, availability, capacity, and security
what does Unified Manager do?
Provides a single management interface for configuring and provisioning resources for applications and services.
Exposes API’s that can be integrated with the orchestration layer to automate service provisioning
Enables adding or removing infrastructure resources to an already provisioned service
Performs compliance checks during resource configuration
Provides a dashboard showing resource configuration and utilization
what are the Three Key Phrases for
Provisioning Resources?
Resource Discovery
Resource Pool Management
Resource Provisioning
What is this a benefit of Resource Discovery?
Provides visibility to each resource. Enables to manage cloud infrastructure resources centrally
What is this a benefit of Resource Pool Management?
Unified Manager allows to grade pools. categorizes resources and identify pools based on predefined criteria.
Helps creating variety of services, providing choices. Cost and price of resource pool differs on the grade level (Gold, Silver, Bronze)
What is the benefit of Resource Provisioning?
Involves allocating resources from graded resources pools to the service instances.
Provisioning commences when consumers select cloud services from the service catalog.
A service template defined in the catalog facilitates consumers to understand service capabilities.
what is Software Defined Approach ?
Abstracts the underlying infrastructure components.
Separates the management functions from the infrastructure components to the external software that runs on a controller - enables controlling IT resources centrally.
what are the Key Functions of the Software Defined Approach?
Discovers underlying resources and provides an aggregated view of resources
Enables rapid provisioning of resources based on predefined policies.
Enables to apply policies uniformly across the infrastructure components
Provides interfaces that enable applications external to the controller to request resources and access them as services
What are these benefits of Software defined approach ?
- Improves business agility
2.provides cost efficiency - enables to achieve scale-out architecture
- provides a central point of access to all management functions
- allows to create new innovative services using underlying resources
what is meant by Resource Management?
Process of allocating resources effectively to a service instance from a pool of resources that help in maintaining service levels
Management server is used to centrally manage resources - enables defining policies, configures and monitors the resources, provides the ability to pool the resources
What are these goals of Resource Management?
- Controls utilization resources.
- Prevents service instances from monopolizing resources.
What are the 2 Resource Allocation Models?
Relative resource allocation and Absolute resource allocation
what is Relative resource allocation relation to a service instance ?
Resource allocation to a service instance is defined proportionally relative to the resource allocated to other service instances
what is Absolute resource allocation?
Resource allocation for a service instance is based on defining a quantitative bound.
what is Hyper Threading?
Makes the process appear as two logical processor cores
Two logical processor cores share the same physical resources
Provides improved performance and utilization
what is Memory Page Sharing?
Eliminates redundant copies of memory pages. Redundant memory pages are reclaimed.
Allows greater degree of memory over-commitment
Hypervisor identifies redundant pages (VM memory pointer is updated to point to shared location, redundant memory pages are reclaimed).
what is Dynamic Memory Allocation?
A memory optimization technique that reclaims memory pages. VMs have agent installed in guest OS that communicates with hypervisor.
In Dynamic memory allocation what happens when memory becomes scarce?
Agent in VM demands memory from their guest OS
Guest OS allocates memory pages to the agent
Agent reserves the memory and puts it back into the memory pool
Hypervisor then assigns the relinquished memory pages to other VMs that require memory
what does VM Load Balancing across Hypervisors do?
Provides uniform distribution of load across hypervisors
what are Key process involved in balancing load of VMs?
Management server checks the availability of resources on all hypervisors when a new VM is powered on.
Management server places the VM on a hypervisor with sufficient resources and ensures that the load is balanced
Management server monitors the load across the hypervisors
what is Server Flash Cache Technology?
Uses intelligent caching software and a flash card on the compute system. Dramatically improves the application performance.
Provides performance acceleration for read-intensive workloads.
Avoids network latencies associated with I/O access to the storage system. Requires warm-up time before significant performance improvement is realized
what is Virtual Storage Provisioning?
It enables to present a LUN to an application with more capacity than is physically allocated to it on the storage system.
Physical storage is allocated to the application on-demand.
Provides more efficient utilization of storage and reduces storage cost. Simplified storage management.
What are the two types of LUNS that can be created in Virtual Storage provisioning?
Thick and Thin LUNS
what is Storage Pool Rebalancing ?
Provides the ability to rebalance allocated extents on physical disk drives over the pool when new drives are added.
Restripes data across all disk drives in the shared storage pool. Helps in achieving higher overall pool performance.
Enables spreading out the data equally on all the drives within the pool. ensures that the used capacity of each drive is uniform across the pool.
what is Storage Space Reclamation?
Identifies unused space in thin LUNs and re-assigns it to the storage pool.
What is a benefit of storage space reclamation?
Provides cost savings
What are the 2 options to reclaim the unused space on a thin LUN?
Zero reclamation and API-based reclamation
what is Zero reclamation?
De-allocate storage extents that contain all zeroes in a thin LUN.
De-allocated extents are added back to the pool
what is API-based reclamation?
API communication the location of all the identified unused space on the LUN to the storage system to reclaim all unused space to the pool
what is API-based reclamation?
A technique of establishing hierarchy of different storage types for different categories of data that enables storing the right data automatically to the right tier, to meet the service level requirements. Each tier has different protection, performance, and cost.
In automated tiering storage what are the two ways data is moved?
Within a storage array or between storage arrays
what is Cache Tiering?
Enables creation of a large capacity secondary cache using SSDs. Enables tiering between DRAM cache and SSDs.
What is this a benefit of Cache Tiering?
Enhances performance during peak workloads and non-disrupting and transparent to applications
Network traffic flow
Controlled to optimize both performance and availability of cloud services
What are the 7 Network Traffic Management techniques?
Balancing client work loads across nodes
Network storm control
Quality of Service (QoS)
Traffic shaping
Link aggregation
NIC teaming
Multipathing
Balancing Client Workload across Nodes
Splits client workload across multiple nodes. Usually performed by a purpose built device called a load balancer.
Where is the load balancer placed?
Between the node and the cluster
Element Manager (definition)
Infrastructure component vendors may provide this type of manager as built in or external software.
This control software is required to manage resources independently
Resource Discovery
Enables the unified manager to learn about resources that are available for service deployment.
what is Network Storm Control?
A networking technique that prevents regular network traffic on a LAN or VLAN from being disrupted by a network storm. A network storm occurs due to flooding of frames on a LAN or VLAN, creating excessive traffic and resulting in degraded network performance.
Quality of Service (QoS)
Capability of a network to prioritize business critical and latency-sensitive network traffic and to provide better service to such traffic over less critical traffic. Enables applications to obtain consistent service levels in terms of network bandwidth, latency variations, and delay.
Traffic Shaping
Limits the traffic rate at a network interface such as a node port or a router port. If traffic rate exceeds the pre-configured limit.
What is this a benefit of Traffic Shaping?
Ensures required service level for business critical applications. controls traffic rate per client/tenant to avoid network congestion
Link Aggregation
combines links between two switches and between a switch and a node. Enables distribution of network traffic across links in the aggregation
NIC Teaming
Distributes network traffic across NIC’s. Provides network failover in the event of a NIC/link failure
Multipathing
Provides load balancing and path failover. Improves I/O performance and data path utilization
