Opentack to learn how to use NOVA:

NOVA (openstack component)

Openstack consists of two main modules: Nova and swift. The former is the virtual server deployment and business computing module developed by NASA, and the latter is the distributed cloud storage module developed by rackspace, which can be used together, it can also be used separately. Nova is the core, with a set of virtualization management programs that can manage networks and storage. The Nova component contains many small components, including API server (NOVA-API), Message Queue (rabbit-MQ server), and compute workers (NOVA-compute), network controller (NOVA-Network), Volume worker (NOVA-volume), and scheduler (NOVA-scheder ). Nova-API is an interactive interface through which managers can manage internal infrastructure or provide services to users. Of course, Web-based management also uses this interface to send messages to message queues for resource scheduling. Rabbit-MQ Server is a message queue in computing resources. It sends messages to each component for resource scheduling. Nova-compute is used to process and manage the instance lifecycle. Receives requests through the message queue and performs operations. The Nova-network is equivalent to a vro in the cloud computing system. It divides IP addresses and configures VLAN and security groups. A component with volume management functions, such as creating a volume, detaching a volume from an instance, deleting a volume, and attaching a volume to an instance. Nova-scheduler is a component that maps Nova-API calls to the open stack function. scheduling decisions are made based on the physical distance, memory, and load of the CPU architecture and available domains. Based on the introduction of the above components, we can see that Nova is a very important core component. Its functions cover almost all fields, such as computing controllers, and are used to manage users' Virtual Machine instances, you can switch on or off the VM, allocate CPU, and use RAM as needed.

Common commands of Nova

Nova list all virtual machines in this project. Nova list -- all-tenants list virtual machines in all projects. Nova start UUID boot. Nova stop UUID shutdown. Nova image-list view all the Nova imagenova volume-List View All the Nova volumenova volume-Attach server-name-or-ID volname device (device-like:/dev/VDA) attach volume to the virtual machine. Nova volume-Detach server-name-or-ID volname: Detach volumenova flavor-list from the virtual machine. view the current virtual machine configuration type. Nova secgroup-list. view the current security group. Nova secgroup-list-rules default view Security Group Rules NOVA show Name-or-ID: view the information of a Virtual Machine (NOVA floating-IP-list) view the list of applied flating IP addresses. Nova Delete name-or-ID: Delete the Virtual Machine (NOVA image-create server-ID "snapshot 1" create snapshotnova image-list to view snapshotnova suspend name-or-ID to suspend Nova resume name-or-ID to restore Nova reboot name-or-ID to restart the Virtual Machine Nova-manage Service list to view the running of the Nova Service view the status of Nova-manage floating List View floating ipnova flavor-list view the configuration template list Nova image-list view the image list Nova secgroup-list view the security rule Nova-manag E service list Nova service list, service physical points and domains, and service status Nova list virtual machines. Before executing this command, you must first run the source account openrc file NOVA show UUID (Virtual Machine ID) you can view the details of the VM, such as the VM name, image template, and startup time. If you want to view the physical point, before executing the command, source administrator openrc file Nova live-migration hot migration Nova evacuate UUID physical node number cold migration VM to new physical point Nova Delete UUID Delete VM Nova reset-state UUID reset VM status Nova reboot -- hard UUID hard restart Nova reset-state-active UUID to reset the VM status to active, if some error VMS cannot be deleted, run this command to delete it. Generally, the VM can be deleted. Nova volume-List View volume list. Nova volume-Attach demo-instance1 volume_id Mount volume to the demo-instance1 VM.

Service components contained by Nova

Controller Nova-API (restful API, a command line-based API)

Nova-schedule (scheduling of computing resources)

Nova-condutor (provides a proxy for crying data connections. If there are too many connections to the database, the database will use a bottleneck ,)

Nova-leleauth (Certification Service)

Nova-novncproxy (VNC proxy)

Nova-Vert (certificate issuance)

Compute Nova-compute (virtual machine sound cycle management, computing node Management of Virtual Machine services)

Clientnova-client Nova-manage (provides O & M management, manages the number of virtual machines, and views the number of computing nodes)

Opentack to learn how to use NOVA: