VOL-1183: OFagent cannot reach vcore after vcore moved to different node in cluster

Two gRPC calls made by OFagent's ConnectionManager, Subscribe and ListLogicalDevices, actually
run in the Twisted reactor thread. On rare occasions, either call never returns when the vcore
connected to the OFagent dies. Because the blocking gRPC runs in the reactor thread, the entire
application is blocked and cannot detect comms errors with the deceased vcore. The handling  of
these gRPCs has been moved to the OFagent's internal GrpcClient, which wraps all gRPC calls in
the twisted.internet.threads.deferToThread function.

Change-Id: Ifa3479a3cbca7ae8d7f5e2ca0372e22507d5e4b9
5 files changed
tree: e07eb6f6a8097f6191a55e64eab58f7149ab040c
  1. .dockerignore
  2. .gitignore
  3. .gitreview
  4. BUILD.md
  5. BuildingVolthaUsingVagrantOnKVM.md
  6. DOCKER_BUILD.md
  7. GettingStartedLinux.md
  8. Jenkinsfile
  9. LICENSE.txt
  10. Makefile
  11. README.md
  12. TODO.md
  13. Vagrantfile
  14. ansible/
  15. cli/
  16. common/
  17. compose/
  18. consul_config/
  19. dashd/
  20. docker/
  21. docs/
  22. env.sh
  23. envoy/
  24. experiments/
  25. fluentd_config/
  26. install/
  27. k8s/
  28. kafka/
  29. netconf/
  30. netopeer/
  31. nginx_config/
  32. obsolete/
  33. ofagent/
  34. pki/
  35. ponsim/
  36. portainer/
  37. reg_config/
  38. requirements.txt
  39. scripts/
  40. settings.vagrant.nightly-docker.yaml
  41. settings.vagrant.nightly.yaml
  42. settings.vagrant.yaml
  43. setup.mk
  44. setup.py
  45. shovel/
  46. tests/
  47. tmp_integration.md
  48. unum/
  49. vagrant-base/
  50. voltha/
README.md

VOLTHA

What is Voltha?

Voltha aims to provide a layer of abstraction on top of legacy and next generation access network equipment for the purpose of control and management. Its initial focus is on PON (GPON, EPON, NG PON 2), but it aims to go beyond to eventually cover other access technologies (xDSL, Docsis, G.FAST, dedicated Ethernet, fixed wireless).

Key concepts of Voltha:

  • Network as a Switch: It makes a set of connected access network devices to look like a(n abstract) programmable flow device, a L2/L3/L4 switch. Examples:
    • PON as a Switch
    • PON + access backhaul as a Switch
    • xDSL service as a Switch
  • Evolution to virtualization: it can work with a variety of (access) network technologies and devices, including legacy, fully virtualized (in the sense of separation of hardware and software), and in between. Voltha can run on a decice, on general purpose servers in the central office, or in data centers.
  • Unified OAM abstraction: it provides unified, vendor- and technology agnostic handling of device management tasks, such as service lifecycle, device lifecycle (including discovery, upgrade), system monitoring, alarms, troubleshooting, security, etc.
  • Cloud/DevOps bridge to modernization: it does all above while also treating the abstracted network functions as software services manageable much like other software components in the cloud, i.e., containers.

Why Voltha?

Control and management in the access network space is a mess. Each access technology brings its own bag of protocols, and on top of that vendors have their own interpretation/extension of the same standards. Compounding the problem is that these vendor- and technology specific differences ooze way up into the centralized OSS systems of the service provider, creating a lot of inefficiencies.

Ideally, all vendor equipment for the same access technology should provide an identical interface for control and management. Moreover, there shall be much higher synergies across technologies. While we wait for vendors to unite, Voltha provides an increment to that direction, by confining the differences to the locality of access and hiding them from the upper layers of the OSS stack.

How can you work with Voltha?

While we are still at the early phase of development, you can check out the BUILD.md file to see how you can build it, run it, test it, etc.

How can you help?

Contributions, small and large, are welcome. Minor contributions and bug fixes are always welcome in form of pull requests. For larger work, the best is to check in with the existing developers to see where help is most needed and to make sure your solution is compatible with the general philosophy of Voltha.