This technique is too pure. |5 minute Learn OpenStack Basics (GO)

Original address: http://mt.sohu.com/20160511/n448800357.shtml

--"from getting started to mastering Cloud server" sixth

The first five periods of "from getting started to mastering Cloud server" have been widely praised, received messages, many readers are interested in cloud computing related technologies. At the request of the audience, we want to amway a pure technical content. Prepare the seeds, peanuts, with the small series into the basic knowledge of OpenStack lecture.

　　Learn about OpenStack

OpenStack is one of the hottest open source software, with an exponential increase in activity; it is a set of open-source projects, at the beginning of which is composed of two projects, currently more than 10 projects; It's a cloud operating system, OpenStack is a-a cloud operating System that ...

OpenStack manages resources that are not single-machine but a distributed system that organizes distributed computing, storage, networking, equipment, and resources to form a complete cloud computing system; OpenStack also provides a UI, which includes a graphical ui:horizon, also provides a command line interface, also provides a set of APIs to enable users to develop their own software ...

OpenStack is software implemented in Python.

The logic of the distributed system is very complex, so in a more advanced language to do, you can put more energy on the logic, rather than the tangle and the bottom of the details, because the high-level language of the underlying mechanism has been optimized very well, the writing-C + + features are not necessarily very high; in fact, in the field of distributed systems, There are many good examples, such as OpenStack written in Python, Hadoop in Java, and UC Berkeley in Scala, and Twitter Storm is developed in the Clojure language, which are Well-known distributed systems that are used in higher-level languages rather than C

　　Features of OpenStack

OpenStack is a set of framework--api, which has two features:

It is a middle tier that can create, manage, and destroy virtual machines, but to do so requires a third-party Hypervisor, and with this Hypervisor to do the virtualization work, OpenStack does not provide a virtualized operating environment on its own. OpenStack has a component called Cinder (to provide a block storage service), but OpenStack does not have the ability to store and read data, it relies on the support of an actual block storage device, which can be a distributed storage system, such as Ceph, It can also be a storage device, such as an EMC SAN or a local hard disk on a storage server, but it must rely on the support of a storage device that OpenStack does not have. OpenStack is a middle tier.

Framework has a very important feature is that it can provide a number of APIs to support the development of the application, which is our industry's definition of the framework, OpenStack of course, the vision is to let users like electricity to use computing , OpenStack Design is also towards this vision to do design, but in fact, we usually can not direct electricity, we need to use refrigerators, computers, televisions and so on these appliances. Similarly, for cloud computing, it is very important to provide APIs to support development applications, and a complete API is a prominent advantage of OpenStack.

　　Openstack≠ virtualization Software

First, it is not a virtualization software (this must be known),although OpenStack manages virtual machines, but does not have the functionality of virtualization , it provides a virtualized environment for the upper layer, must rely on a third-party virtualization software, such as the default supported Linux The kernel virtual machine, which is automatically brought after Linux, is integrated into the Linux kernel (KVM), supports Xen, supports Microsoft's Hyper-V, supports VMware's Vshpere, and supports Linux Container and Docker as well. Lightweight virtualization technology. In summary, OpenStack itself does not provide virtualization and relies on third-party software.

Need to understand the second layer of meaning: this cloud and virtualization is actually not the same, cloud! = Virtualization, the purpose of cloud is to achieve utility computing, elastic Computing, dynamic resource scheduling, multi-tenancy, and other such characteristics; virtualization is just one of the technical means of implementing these features of cloud computing, And it's not necessary. IBM's Softlayer, for example, is one of IBM's main cloud services, and one of its big features is that it supports bare Metal Server, which is literally "bare metal", which is that SoftLayer does not virtualize, but directly uses physical To the cloud, directly to the user, the tenant is the physical server, Softlayer can also be on the above to achieve multi-tenancy, elastic Computing and so on features. In short, SoftLayer is not virtualized, but SoftLayer also does the cloud. The second example is that OpenStack also has a project called Ironic, which is designed to implement cloud-based projects by managing "bare metal".

　　OpenStack Resource Management

OpenStack as an operating system, management of resources is its primary task;

There are three main aspects of OpenStack management resources: compute, storage, and networking.

OpenStack manages resources and provides it to upper-level applications or users in the form of services. The management of these resources is achieved through the various projects in OpenStack.

One of the projects related to computing resource management is Nova (also known as OpenStack Compute);

Storage related to the main block storage service Cinder, object Storage service Swift, mirrored storage service Glance these three kinds;

The main network-related project is a software-defined network-related item called Neutron; In addition, the Nova network is a module that manages the networks, and as a relatively stable legacy component still exists in OpenStack and Neutron, We are often in the small-scale deployment to pursue this stability, and reduce the workload will use a component such as the Nova network to manage Web resources.

This technique is too pure. |5 minute Learn OpenStack Basics (GO)