Difference between revisions of "Obsolete:ArchitecturalOverview"
(Added bulleted list from Vish's mailing list post, will put the rest of the details in another page) |
|||
| Line 1: | Line 1: | ||
__NOTOC__ | __NOTOC__ | ||
| − | == Architectural Overview == | + | == Architectural Overview for [[OpenStack]] Compute == |
Live Notes may be taken for this topic at: http://etherpad.openstack.org/Architecture | Live Notes may be taken for this topic at: http://etherpad.openstack.org/Architecture | ||
| Line 31: | Line 31: | ||
=== Datastore === | === Datastore === | ||
| − | * | + | * Pre-Austin, data is stored in Redis 2.0 (RC) |
* Do the work on write - make reads FAST | * Do the work on write - make reads FAST | ||
** maintain indexes / lists of common subsets | ** maintain indexes / lists of common subsets | ||
| Line 41: | Line 41: | ||
* Object store in Nova is a naive stub which would be replaced with Cloud Files in Production (a simple object store that mimics Cloud Files might be good for development) | * Object store in Nova is a naive stub which would be replaced with Cloud Files in Production (a simple object store that mimics Cloud Files might be good for development) | ||
* Tornado should be phased out for WSGI-based web framework | * Tornado should be phased out for WSGI-based web framework | ||
| + | |||
| + | === Networking === | ||
| + | Currently, there are three strategies for networking, implemented by different managers: | ||
| + | * [[FlatManager]] -- ip addresses are grabbed from a network and injected into the image on launch. All instances are attached to the same manually configured bridge. | ||
| + | * FlatDHCPManager -- ip addresses are grabbed from a network, and a single bridge is created for all instances. A dhcp server is started to pass out addresses | ||
| + | * [[VlanManager]] -- each project gets its own vlan, bridge and network. A dhcpserver is started for each vlan, and all instances are bridged into that vlan. | ||
| + | |||
| + | The implementation of creating bridges, vlans, dhcpservers, and firewall rules is done by the driver linux_net. This layer of abstraction is so that we can at some point support configuring hardware switches etc. using the same managers. | ||
Revision as of 20:05, 15 October 2010
Architectural Overview for OpenStack Compute
Live Notes may be taken for this topic at: http://etherpad.openstack.org/Architecture
File:ArchitecturalOverview$overview.png
“Small” components, loosely coupled
- Queue based (currently AMQP/RabbitMQ)
- Flexible schema for datastore (currently Redis)
- LDAP (allows for integration with MS Active Directory via translucent proxy)
- Workers & Web hooks (be of the web)
- Asynchronous everything (don't block)
- Components (queue, datastore, http endpoints, ...) should scale independently and allow visibility into internal state (for the pretty charts/operations)
Development goals
- Testing & Continuous Integration
- Fakes (allows development on a laptop)
- Adaptable (goal is to make integration with existing resources at organization easier)
Queue
- Each worker/agent listens on a general topic, and a subtopic for that node. Example would be "compute" & "compute:hostname"
- Messages in the queue are currently Topic, Method, Arguments - which maps to a method in the python class for the worker
- exposed via method calls
- rpc.cast to broadcast the message and not wait for a response
- rpc.call to send a message and wait for the response
Datastore
- Pre-Austin, data is stored in Redis 2.0 (RC)
- Do the work on write - make reads FAST
- maintain indexes / lists of common subsets
- use pools (SETs in redis) that are drained for IPs instead of tracking what is allocated
Delta
- Scheduler does not exist (instances are distributed via the queue to the first worker that consumes the message)
- Object store in Nova is a naive stub which would be replaced with Cloud Files in Production (a simple object store that mimics Cloud Files might be good for development)
- Tornado should be phased out for WSGI-based web framework
Networking
Currently, there are three strategies for networking, implemented by different managers:
- FlatManager -- ip addresses are grabbed from a network and injected into the image on launch. All instances are attached to the same manually configured bridge.
- FlatDHCPManager -- ip addresses are grabbed from a network, and a single bridge is created for all instances. A dhcp server is started to pass out addresses
- VlanManager -- each project gets its own vlan, bridge and network. A dhcpserver is started for each vlan, and all instances are bridged into that vlan.
The implementation of creating bridges, vlans, dhcpservers, and firewall rules is done by the driver linux_net. This layer of abstraction is so that we can at some point support configuring hardware switches etc. using the same managers.
