What do you understand by the term Openstack?
Openstack is defined because the way forward for cloud computing wherein Openstack are often used for handling an outsized group of virtual machines with the assistance of the graphical interface. The working of Openstack is analogous to Linux and it’s free and open-source.
What are the key features of Openstack?
Following are the key features of Openstack:
- Horizon: It is the first key feature through which administrators get an idea about the functioning of the cloud.
- Nova: It is used for handling multiple virtual machines and other computing tasks.
- Swift: It is used for understanding the storage system.
- Cinder: It is used as a block storage system so as to access files at a faster speed.
- Neutron: It is used for building the connectivity between the components while they are developed.
- Keystone: It is used for providing the identity list and is used as mapping techniques.
How many types of storages are provided by the Openstack?
Openstack provides two types of storages:
- Ephemeral storage
- Persistent storage
What are the three types of persistent storage provided by Openstack?
Following are the three types of persistent storage provided by Openstack:
- Object storage
- Block storage
- File-based storage
What does the term “object storage” mean?
Object storage is applied in Openstack with the help of Object Storage service (swift). With the help of REST API, users can access binary objects. Following are the other advantages of object storage:
Openstack stores all its virtual machine images in the object storage system.
Object storage works with the Openstack dashboard.
Object storage systems can be used for multiple data centers.
What does the term “block storage” mean?
Block storage is applied in Openstack with the help of Block storage service (cinder). Block storage provides multiple back ends in the form of drivers. Since it is persistent storage it can be detached and reattached from one instance to another.
Name the three important modular architecture of Openstack.
Following are the three important modular architecture of Openstack:
- Openstack compute: It is used for managing large networks on the virtual machine.
- Image service: It is used for providing delivery service for discovering and registering of the virtual machine images.
- Openstack object storage: It is used as a storage system provides support for two different storage: object storage and block storage.
What do you understand by Python SDK in Openstack?
SDK stands for Software Development Kit which is used for writing scripts related to python. It provides a platform for Openstack where all the services are done in one place. It consists of languages that bind access to the OpenStack clouds, and complete API reference with easy interaction with REST API.
What does token mean in Openstack?
Token is defined as a type of authentication which is similar to password-based validation. Once the credentials are inserted by the user, the token gets generated through which the user gets authentication for keystone. With the generated token, the user can access the Openstack. The token comes for a limited time period. Once the time period is exceeded, it has to be renewed again.
List down the type of Hypervisors supported by OpenStack.
- KVM (Kernel-based Virtual machine)
- LXC: Linux Containers having Linux-based VMs
- QEMU: Quick EMUlator used for development purposes
- UML: User Mode Linux used for development purposes
- VMware vSphere: VMware-based Linux and Windows via vCenter server connection.
- Hyper-V: Server virtualization with Microsoft’s Hyper-V
Define Identity Service in OpenStack.
Keystone is the most important and preferred Identity Service in OpenStack and executes the complete OpenStack Identity API. The Keystone Identity Service is responsible for user management and service catalog. In user management, it tracks users and their permissions while Service Catalog offers a list of services available with their API. The former provides authentication credential details of users, tenants, and roles.
What is Token?
Token is a type of authentication similar to password-based validation. A token gets generated once the user inserts the credentials and authenticates as a Keystone user. The token can then be used to access OpenStack services without any revalidation. It is interesting to note that a token is active for a limited period and must be renewed after regular intervals. To create a token, users first need to authenticate their Keystone credentials.
What is OpenStack Python SDK?
Answer: Python SDK (Software Development Kit) helps users to write applications for performing automation tasks in Python by calling Python objects. It provides a platform to work with multiple OpenStack services at one place. It consists of language bindings to access OpenStack clouds, complete API reference, easy interaction with REST API and sample code for initial applications.
Tell me the command on how to spin a VM from Command Line?
We can easily spin a new VM using the following openstack command,
# openstack server create –flavor {flavor-name} –image {Image-Name-Or-Image-ID} –nic net-id={Network-ID} –security-group {Security_Group_ID} –key-name {Keypair-Name} <VM_Name>
What is the meaning of the term ‘Flavor’ in OpenStack?
OpenStack provides various hardware templates which are found virtually and they are known as Flavor. Generally, the size of the memory of any hard disk and RAM is defined by it. In fact, various components like Name, ID, Disk, Memory are all illustrated by it. The flavor can be modified in the OpenStack.
What is Hypervisor?
VMM which is the abbreviation of virtual machine monitor is basically defined by the Hypervisor. It is also used to define various components like firmware, hardware, and software. All these are part of the virtual machine. A hypervisor is mainly consisted or included by the host machine or various other virtually available machines. Multiple Hypervisor is also available in the OpenStack developmental software program and can choose accordingly catering to specific uses.
What work does the Filter Scheduler do?
If there is an instance of creating some new functions, the notification is mainly given by the Filter Scheduler. It also helps in filtering these notifications according to their importance. Compute Nodes are the ones with whom it works. The hosts which are unfiltered gets created at first and by the help of their specific properties, it gets filtered. Such filtered hosts are needed according to the total number of instances.
How do Swift functions?
Swift helps in storing various objects. It helps in storing objects which are bigger in size and is also numerous in numbers. It helps in reducing data by storing such objects. Its works are often associated with the large number of sets of data. It contains data that is needed for virtual machines and other apps. Swift also has the capability of media streaming and can also secure a large number of objects stored by it. It has extreme scalability skills and can also help in backing up files and data.
Define the Sanitization Process.
The sanitization process refers to the process of the removal of certain information that is present in the media. This type is information is basically useless as these can’t be reconstructed or retrieved. This process mainly includes various techniques like purging, clearing, erasing cryptographically, and also destruction. Such a process prevents the information to get out to any individuals who are unauthorized during the releases of such information in the media.
How can you overcome any type of sudden server failure?
During the failure of the server or when the server is not seen to be perfectly functioning then the Object Storage services should not be running. Hence, it is best to close them of this problem arises. This is because to know the solution, troubleshooting must be done.
Closing the object storage service will allow it to work or function while troubleshooting is still going on. However, often such failure just needs rebooting and hence for this work which doesn’t require much time, the object storage service doesn’t need to be closed. Update to this service will be added once the machine gets online after rebooting.
Removing the drive from the ring is the best idea when the drive can’t be replaced. But if it can be replaced, then it can be added back to the ring.
What is an Identity Service in OpenStack?
Keystone executes the complete API for OpenStack therefore it is the most preferred identity service in OpenStack. The Keystone Identity offers service cataloging and user management. In service catalog, a list of available services are listed in API while in user management users and their respective access permissions are tracked. They are also responsible for providing authentication credential information of users, tenants and roles. Policy and token services are also carried out by Keystone Identity.
Explain networking techniques used in OpenStack?
Flat DHCP Network Manager: In this technique, IP addresses are fetched from the subnet for virtual machine instances but IP addresses to VM are allocated by using DHCP (Dynamic Host Configuration Protocol).
Flat Network Manager: In this technique, IP addresses are fetched from the subnet for VM instances, and then inserted into the image while launching.
VLAN Network Manager: VLAN is better and more preferred than the above two techniques as it offers a separate and secure network to virtual machines. There is a physical switch to provide a separate virtual network and separate IP range and bridge to every tenant.
What does the term “object storage” mean?
Object storage is applied in Openstack with the help of Object Storage service (swift). With the help of REST API, users can access binary objects. Following are the other advantages of object storage:
Openstack stores all its virtual machine images in the object storage system.
Object storage works with the Openstack dashboard.
Object storage systems can be used for multiple data centers.
What does the term “block storage” mean?
Block storage is applied in Openstack with the help of Block storage service (cinder). Block storage provides multiple back ends in the form of drivers. Since it is persistent storage it can be detached and reattached from one instance to another.
What does the term “file-based storage” mean?
The file-based storage system in Openstack provides a set of services that are used for managing multiple files at the same time and also can be exchanged with multiple users at the same time.