The document discusses the components of OpenStack Nova and their roles. It describes nova-api, nova-conductor, nova-scheduler, and nova-compute. Nova-api handles user requests and initiates orchestration activities. Nova-conductor acts as an intermediary between the database and compute nodes. Nova-scheduler determines which compute node to place new instances on. Nova-compute runs on compute nodes and creates/terminates VMs using hypervisor APIs.

1. Nova
OpenStack Study 3rd
클라우드개발팀 신진호

2. Installations
# yum install nova-api nova-cert nova-conductor nova-consoleauth nova-novncproxy
nova-scheduler python-novaclient
# yum install nova-compute
On Controller Node
On Compute Node
Where is nova-network!!!?
What is cert? novncproxy?
Openstack Icehouse

3. Components
nova-novncproxy
nova-cert
nova-consoleauth
nova-network
nova-api-metadata
nova-api nova-conductor
nova-scheduler nova-computequeue
database

4. Components
nova-novncproxy
nova-cert
nova-consoleauth
nova-network
nova-api-metadata
nova-api nova-conductor
nova-scheduler nova-computequeue
database

5. Components
nova-novncproxy
nova-cert
nova-consoleauth
nova-network
nova-api-metadata
Neutron
nova-api nova-conductor
nova-scheduler nova-computequeue
database

6. Components
nova-novncproxy
nova-cert
nova-consoleauth
nova-api nova-conductor
nova-scheduler nova-computequeue
database

7. Components
nova-api nova-conductor
nova-scheduler nova-computequeue
database

8. Components > nova-api
nova-api nova-conductor
nova-scheduler nova-computequeue
database
HTTP Web Service!
Accepts & Responds to User’s Compute API calls
Supports OpenStack Compute API, Amazon EC2
API, Admin API.
Initiates Orchestration Activities.
POST /v2/{tenant_id}/servers/{server_id}/action

9. Components > nova-api
POST /v2/{tenant_id}/servers
Request Body
{
"server": {
"name": "server-test-1",
"imageRef": "b5660a6e-4b46-4be3-9707-6b47221b454f",
"flavorRef": "2",
"max_count": 1,
"min_count": 1,
"networks": [
{
"uuid": "d32019d3-bc6e-4319-9c1d-6722fc136a22"
}
],
"security_groups": [
{
"name": "default"
},
{
"name": "another-secgroup-name"
}
]
}
}
202 Accepted
Response Body
{

10. Components > nova-conductor
nova-api nova-conductor
nova-scheduler nova-computequeue
database
Database Proxy!
Acting as an intermediary between the compute
node and the database node and the database.

11. Components > nova-conductor
Why?
Auditing database operations, revoking access privileges.
That’s Difficult!
They host tenant instances.
Compute nodes are the least trusted of the services in OpenStack.

12. Components > nova-conductor
They strongly recommends
Be isolated to a management network,
Use SSL,
Create unique user accounts per service endpoint.

13. Restrict services to executing with parameters, …
Prevent directly accessing or modifying.
Unfortunately, it complicates fine-grained access control
and audit data access.
Because, it Focus on improving Security, effectively modifying.
Components > nova-conductor
-> Compute nodes are the least trusted
of the services in OpenStack. Because they host tenant instances.
-> Do not deploy it on Compute Nodes.

14. Components > nova-conductor
nova-api nova-conductor
nova-scheduler nova-computequeue
database
push
pop
push
pop

15. Components > nova-scheduler
nova-api nova-conductor
nova-scheduler nova-computequeue
database
Scheduler!
Takes VM requests from the queue.
Determine on which compute node host it.

16. Components > nova-scheduler
nova-api nova-conductor
nova-scheduler queue
mysql
nova-compute1
nova-compute2
nova-compute3
NEW Instance
Instance B
takes
determines
Create Instance

17. Components > nova-compute
nova-api nova-conductor
nova-scheduler nova-computequeue
database
Worker Daemon!
Creates and terminates VMs through hypervisor APIs,
such as Xen, QEMU, KVM, Vmware, ….

18. It Supports multiple hypervisors.
Because, it Has an abstraction layer, Driver.
Components > nova-compute
nova-compute
Compute Agent
(KVM)
libvirt
KVM
VM VM
nova-compute
Compute Agent
(Hyper-v)
Hyper-v
VM VM
nova-scheduler
nova-compute
Abstraction layer,
Driver
any hypervisor
VM VM

19. Components > nova-compute
nova-api nova-conductor
nova-scheduler
nova-compute
queue
database
hypervisor
VM
VM launch
takes
determines

20. Components > nova-compute
keystone
Glance
Neutron
Cinder
Horizon or CLI
4
5
3
1
2
In more detail…
Provisioning Instance

21. Links
• Deprecation of Nova Network
– http://docs.openstack.org/openstack-ops/content/nova-network-deprecation.html
• Compute service
– http://docs.openstack.org/icehouse/install-guide/install/apt/content/compute-service.html
• Chapter 33. Database access control
– http://docs.openstack.org/security-guide/content/ch042_database-overview.html
• VNC console proxy
– http://docs.openstack.org/admin-guide-cloud/content/getting-started-with-vnc-proxy.html
• EC2 compatibility API
– http://docs.openstack.org/admin-guide-cloud/content/instance-mgmt-ec2compat.html
• nova-cert
– http://docs.openstack.org/developer/nova/man/nova-cert.html
• Laurent Luce's Blog > OpenStack Nova internals of instance launching
– http://www.laurentluce.com/posts/openstack-nova-internals-of-instance-launching/
• Request Flow for Provisioning Instance in Openstack
– http://ilearnstack.com/2013/04/26/request-flow-for-provisioning-instance-in-openstack/

22. Next Week…
• nova-compute
– driver
– hypervisor support matrix
– …
• nova-scheduler
– filters
– host aggregates
– …
• availability zone
• initialization of a cloud instance
– cloud-init
– file injection
• migration
– migrate instances

23. EOF