feat(v2): storage network with v2 data engine

[c3y1huang]

Which issue(s) this PR fixes:

Issue longhorn/longhorn#6450

What this PR does / why we need it:

Use storage network for V2 data engine.

Special notes for your reviewer:

None

Additional documentation or context

None

[coderabbitai]

Walkthrough

This pull request modifies how storage IP addresses are handled during instance creation. In the engine controller, it adds logic to retrieve the instance manager pod and use its storage IP when setting the InitiatorAddress and TargetAddress for engine instances, along with enhanced error handling. In the replica controller, it removes the assignment of the ImIP field. Additionally, the ImIP field is removed from both EngineInstanceCreateRequest and ReplicaInstanceCreateRequest in the engine API.

Changes

File(s)	Change Summary
controller/engine_controller.go	Added logic to retrieve the instance manager pod via ec.ds.GetPod(im.Name); updated EngineInstanceCreateRequest to use the pod’s storage IP; enhanced error handling.
controller/replica_controller.go	Removed the line that sets the ImIP field in the ReplicaInstanceCreateRequest.
engineapi/instance_manager.go	Removed the ImIP field from both EngineInstanceCreateRequest and ReplicaInstanceCreateRequest structures.

Sequence Diagram(s)

Engine Instance Creation Flow

sequenceDiagram
    participant EC as EngineController
    participant DS as DataStore
    participant Pod as Instance Manager Pod
    participant ES as EngineService

    EC->>DS: GetPod(instanceManagerName)
    DS-->>EC: Pod (with storage IP)
    EC->>ES: CreateEngineInstance(InitiatorAddress & TargetAddress = storage IP)
    ES-->>EC: Instance process created

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Replica Instance Creation Flow

sequenceDiagram
    participant RC as ReplicaController
    participant ES as EngineService

    RC->>ES: CreateReplicaInstance(without IM IP)
    ES-->>RC: Instance process created

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Assessment against linked issues

Objective	Addressed	Explanation
Update instance creation logic to use pod-derived storage IP and remove deprecated IP configuration (#6450)	✅

Suggested reviewers

• shuo-wu
• innobead

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📥 Commits

Reviewing files that changed from the base of the PR and between e3492b6 and d78b240.

📒 Files selected for processing (3)

• controller/engine_controller.go (1 hunks)
• controller/replica_controller.go (0 hunks)
• engineapi/instance_manager.go (0 hunks)

💤 Files with no reviewable changes (2)

• engineapi/instance_manager.go
• controller/replica_controller.go

⏰ Context from checks skipped due to timeout of 90000ms (2)

• GitHub Check: Build binaries
• GitHub Check: Summary

🔇 Additional comments (2)

controller/engine_controller.go (2)

485-490: LGTM! Proper error handling for pod retrieval.

The implementation correctly retrieves the instance manager pod and extracts the storage IP with appropriate error handling.

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500-501: LGTM! Consistent use of storage network IP.

The implementation correctly uses the storage network IP for both initiator and target addresses, replacing the previous use of instance manager IP.

✨ Finishing Touches

• 📝 Generate Docstrings (Beta)

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[c3y1huang]

Test result:

• -m v2_volume_test:

  > k -n longhorn-system get setting storage-network
  NAME              VALUE                          APPLIED   AGE
  storage-network   kube-system/demo-192-168-0-0   true      26h
  

  =========================== short test summary info ============================
  FAILED test_scheduling.py::test_data_locality_basic - AssertionError
  
  = 1 failed, 130 passed, 1 skipped, 258 deselected, 136 warnings in 24429.59s (6:47:09) =
  

  Known issue: [BUG] V2 volume fails to cleanup error replica and rebuild new one - test_data_locality_basic longhorn#10335
• Backing image (manual):
  • create backing image with v2 data engine
  • create and attach volume with v2 data engine backing image

[derekbit]

LGTM

[ChanYiLin]

Hi @c3y1huang
Could you please check if there is anything also needs to be changed for the v2 BackingImage?
V2 BackingImage is managed by instance-manager

There is only one place where it may need the instance-manager ip, not sure if in this case will we need to pass the storage network ip instead of pod ip.

• longhorn-manager use engine proxy api to send request to instance manger to create the BackingImage in the spdk server
• When syncing BackingImage between each instance-manager, e.g. from A to B
  • longhorn-manager get the srcInstanceManager.Status.IP of the copy A
  • _, err = engineClientProxy.SPDKBackingImageCreate(bi.Name, bi.Status.UUID, v2DiskUUID, bi.Status.Checksum, net.JoinHostPort(srcInstanceManager.Status.IP, strconv.Itoa(engineapi.InstanceManagerSpdkServiceDefaultPort)), sourceV2DiskUUID, bi.Name, uint64(bi.Status.Size))
  • the B instance-manager spdk server will use this ip address to get the client.NewSPDKClient(addr) to ask A to expose the spdk snapshot and connect it to get the device to do the copy.