refactor(cli): scope --connector to TensorRT-LLM

components/src/dynamo/common/configuration/groups/runtime_args.py

@@ -32,7 +32,6 @@ class DynamoRuntimeConfig(ConfigBase):
     request_plane: str
     event_plane: Optional[str] = None
     fpm_trace: bool = False
-    connector: list[str]
     enable_local_indexer: bool = True
 
     dyn_tool_call_parser: Optional[str] = None
@@ -199,14 +198,6 @@ def add_arguments(self, parser: argparse.ArgumentParser) -> None:
             default=False,
             help="Persist backend forward-pass metrics to rotating gzip JSONL trace files. Also enables the backend FPM instrumentation required to produce those records.",
         )
-        add_argument(
-            g,
-            flag_name="--connector",
-            env_var="DYN_CONNECTOR",
-            default=[],
-            help="[Deprecated for vLLM] Use --kv-transfer-config instead. For TRT-LLM, options: nixl, lmcache, kvbm, null, none.",
-            nargs="*",
-        )
 
         # Optional: tool/reasoning parsers (choices from dynamo._core when available)
         add_argument(

components/src/dynamo/trtllm/args.py

@@ -49,7 +49,6 @@ class Config(DynamoRuntimeConfig, DynamoTrtllmConfig):
     # Routing this worker set advertises in its model card; None inherits the
     # frontend's configuration.
     router_advertisement: Optional[WorkerRouterConfig] = None
-    connector: list[str]  # Redeclare for mypy (inherited from DynamoRuntimeConfig)
 
     def validate(self) -> None:
         DynamoRuntimeConfig.validate(self)
@@ -65,14 +64,11 @@ def validate(self) -> None:
                     "TRT-LLM supports at most one connector entry. Use `--connector none` or `--connector kvbm`."
                 )
             elif self.connector[0] not in VALID_TRTLLM_CONNECTORS:
-                source = (
-                    f"DYN_CONNECTOR environment variable ('{os.environ['DYN_CONNECTOR']}')"
-                    if "DYN_CONNECTOR" in os.environ
-                    else f"shared runtime default ('{self.connector[0]}')"
-                )
                 logging.warning(
-                    f"TRT-LLM does not support connector '{self.connector[0]}' (set via {source}). "
-                    f"Supported connectors: {VALID_TRTLLM_CONNECTORS}. Falling back to 'none'."
+                    "TRT-LLM does not support connector '%s'. "
+                    "Supported connectors: %s. Falling back to 'none'.",
+                    self.connector[0],
+                    VALID_TRTLLM_CONNECTORS,
                 )
                 self.connector = ["none"]
 

components/src/dynamo/trtllm/backend_args.py

@@ -105,6 +105,15 @@ def add_arguments(self, parser: argparse.ArgumentParser) -> None:
             "Dynamo router's selected rank and requires a TensorRT-LLM build containing "
             "NVIDIA/TensorRT-LLM#16815 or equivalent.",
         )
+        add_argument(
+            g,
+            flag_name="--connector",
+            env_var="DYN_CONNECTOR",
+            default=[],
+            help="KV cache connector for the TensorRT-LLM engine. Accepts at most "
+            "one value: 'kvbm' enables the KVBM integration, 'none' disables it.",
+            nargs="*",
+        )
         add_argument(
             g,
             flag_name="--kv-block-size",
@@ -490,6 +499,7 @@ class DynamoTrtllmConfig(ConfigBase):
     enable_attention_dp: bool
     conversation_affinity: bool
     conversation_affinity_dp_rank_source: str
+    connector: list[str]
     kv_block_size: int
     gpus_per_node: Optional[int] = None
     max_batch_size: int

components/src/dynamo/vllm/args.py

@@ -3,7 +3,6 @@
 
 import argparse
 import ipaddress
-import json
 import logging
 import os
 import socket
@@ -224,9 +223,6 @@ def update_dynamo_config_with_engine(
                 "Please ensure the file exists and the path is correct."
             )
 
-    # --connector is no longer supported for vLLM. Raise hard error if explicitly set.
-    _reject_connector_flag(dynamo_config)
-
     # If disaggregation mode is prefill, require explicit --kv-transfer-config
     has_kv_transfer_config = (
         hasattr(engine_config, "kv_transfer_config")
@@ -237,16 +233,12 @@ def update_dynamo_config_with_engine(
         and not has_kv_transfer_config
     ):
         raise ValueError(
-            "--connector is deprecated and the default is no longer nixl. "
             "When using --disaggregation-mode prefill, you must explicitly "
             "provide --kv-transfer-config. Example:\n"
             "  --kv-transfer-config "
             '\'{"kv_connector":"NixlConnector","kv_role":"kv_both"}\''
         )
 
-    # Clear connector list (no longer used for vLLM)
-    dynamo_config.connector = []  # type: ignore[assignment]
-
 
 def _unsupported_fpm_trace_role(dynamo_config: Config) -> Optional[str]:
     """Return the worker role when trace-based FPM activation is unsupported."""
@@ -490,98 +482,6 @@ def _uses_dynamo_connector(engine_config: AsyncEngineArgs) -> bool:
     return False
 
 
-def _connector_to_kv_transfer_json(connectors: list[str]) -> str:
-    """Convert a legacy --connector list to the equivalent --kv-transfer-config JSON.
-
-    Used in error messages to help users migrate.
-    """
-    multi_connectors = []
-    for conn in connectors:
-        c = conn.lower()
-        if c == "lmcache":
-            multi_connectors.append(
-                {"kv_connector": "LMCacheConnectorV1", "kv_role": "kv_both"}
-            )
-        elif c == "flexkv":
-            multi_connectors.append(
-                {"kv_connector": "FlexKVConnectorV1", "kv_role": "kv_both"}
-            )
-        elif c == "nixl":
-            multi_connectors.append(
-                {"kv_connector": "NixlConnector", "kv_role": "kv_both"}
-            )
-        elif c == "kvbm":
-            multi_connectors.append(
-                {
-                    "kv_connector": "DynamoConnector",
-                    "kv_connector_module_path": "kvbm.vllm_integration.connector",
-                    "kv_role": "kv_both",
-                }
-            )
-
-    if len(multi_connectors) == 1:
-        return json.dumps(multi_connectors[0])
-
-    return json.dumps(
-        {
-            "kv_connector": "PdConnector",
-            "kv_role": "kv_both",
-            "kv_connector_extra_config": {"connectors": multi_connectors},
-            "kv_connector_module_path": "kvbm.vllm_integration.connector",
-        }
-    )
-
-
-def _reject_connector_flag(dynamo_config: Config) -> None:
-    """Raise ValueError if --connector was explicitly set (CLI or DYN_CONNECTOR env var).
-
-    The --connector flag is no longer supported for the vLLM backend.
-    Users must use --kv-transfer-config instead.
-    """
-    connector_list = dynamo_config.connector or []
-
-    # Check if --connector was explicitly provided via CLI or DYN_CONNECTOR env var
-    env_connector = os.environ.get("DYN_CONNECTOR")
-    explicitly_set = bool(connector_list) or (env_connector is not None)
-
-    if not explicitly_set:
-        return
-
-    # Normalize: "none"/"null" means no connector
-    normalized = [c.lower() for c in connector_list]
-    if normalized and all(c in ("none", "null") for c in normalized):
-        # --connector none/null: tell user it's no longer needed
-        raise ValueError(
-            "--connector is no longer supported for the vLLM backend. "
-            "'--connector none' is no longer needed — the default is already "
-            "no connector. Simply remove the --connector flag."
-        )
-
-    # Active connectors: show migration path
-    if normalized:
-        equiv = _connector_to_kv_transfer_json(normalized)
-        raise ValueError(
-            "--connector is no longer supported for the vLLM backend. "
-            "Use --kv-transfer-config instead.\n"
-            f"  Equivalent: --kv-transfer-config '{equiv}'"
-        )
-
-    # DYN_CONNECTOR env var set but parsed to empty list
-    if env_connector is not None:
-        env_values = [v.strip().lower() for v in env_connector.split() if v.strip()]
-        if env_values and not all(v in ("none", "null") for v in env_values):
-            equiv = _connector_to_kv_transfer_json(env_values)
-            raise ValueError(
-                "The DYN_CONNECTOR environment variable is no longer supported "
-                "for the vLLM backend. Use --kv-transfer-config instead.\n"
-                f"  Equivalent: --kv-transfer-config '{equiv}'"
-            )
-        raise ValueError(
-            "The DYN_CONNECTOR environment variable is no longer supported "
-            "for the vLLM backend. Use --kv-transfer-config instead."
-        )
-
-
 def get_host_ip() -> str:
     """Get a routable IP address of the host for NIXL side-channel coordination.
 

components/src/dynamo/vllm/tests/omni/test_omni_args.py

@@ -55,7 +55,6 @@ def _make_omni_config(**overrides) -> OmniConfig:
         "discovery_backend": "etcd",
         "request_plane": "tcp",
         "event_plane": "nats",
-        "connector": [],
         "enable_local_indexer": True,
         "dyn_tool_call_parser": None,
         "dyn_reasoning_parser": None,

components/src/dynamo/vllm/tests/test_vllm_unit.py

@@ -20,7 +20,6 @@
 import dynamo.llm as dynamo_llm
 from dynamo.vllm import envs
 from dynamo.vllm.args import (
-    _connector_to_kv_transfer_json,
     _is_routable,
     _uses_dynamo_connector,
     _uses_nixl_connector,
@@ -234,31 +233,6 @@ def test_removed_multimodal_role_flags_are_rejected(flag, mock_vllm_cli):
         parse_args()
 
 
-# --connector removal tests
-
-
-def test_connector_nixl_raises_error_with_migration_hint(mock_vllm_cli):
-    """Test that --connector nixl raises ValueError with --kv-transfer-config hint."""
-    mock_vllm_cli("--model", "Qwen/Qwen3-0.6B", "--connector", "nixl")
-    with pytest.raises(ValueError, match="--connector is no longer supported"):
-        parse_args()
-
-
-def test_connector_none_raises_error(mock_vllm_cli):
-    """Test that --connector none raises ValueError telling user it's no longer needed."""
-    mock_vllm_cli("--model", "Qwen/Qwen3-0.6B", "--connector", "none")
-    with pytest.raises(ValueError, match="no longer needed"):
-        parse_args()
-
-
-def test_env_var_dyn_connector_raises_error(monkeypatch, mock_vllm_cli):
-    """Test that DYN_CONNECTOR env var raises error for vLLM backend."""
-    monkeypatch.setenv("DYN_CONNECTOR", "nixl")
-    mock_vllm_cli("--model", "Qwen/Qwen3-0.6B")
-    with pytest.raises(ValueError, match="no longer supported"):
-        parse_args()
-
-
 def test_model_express_url_is_accepted_for_compatibility(mock_vllm_cli):
     """Test that legacy ModelExpress manifests still parse."""
     mock_vllm_cli(
@@ -292,22 +266,6 @@ def test_prefill_worker_without_kv_transfer_config_raises(mock_vllm_cli):
         parse_args()
 
 
-def test_connector_to_kv_transfer_json_single():
-    """Test _connector_to_kv_transfer_json returns valid JSON for a single connector."""
-    result = json.loads(_connector_to_kv_transfer_json(["nixl"]))
-    assert result == {"kv_connector": "NixlConnector", "kv_role": "kv_both"}
-
-
-def test_connector_to_kv_transfer_json_multi():
-    """Test _connector_to_kv_transfer_json wraps multiple connectors in PdConnector."""
-    result = json.loads(_connector_to_kv_transfer_json(["kvbm", "nixl"]))
-    assert result["kv_connector"] == "PdConnector"
-    nested = result["kv_connector_extra_config"]["connectors"]
-    nested_names = [c["kv_connector"] for c in nested]
-    assert "DynamoConnector" in nested_names
-    assert "NixlConnector" in nested_names
-
-
 # _uses_nixl_connector / _uses_dynamo_connector tests
 
 

docs/fern/pages/reference/backends/tensorrt-llm-configuration.mdx

@@ -160,6 +160,14 @@ Each field is both a CLI flag and an environment variable. The CLI flag takes pr
   Environment variable: `DYN_TRTLLM_PUBLISH_KV_EVENTS`
 </ParamField>
 
+<ParamField path="--connector" type="string" default="null">
+  KV cache connector for the TensorRT-LLM engine. Accepts at most one value: `kvbm` enables the [KVBM](../../developer-guide/knowledge-base/modular-components/kvbm/kvbm-guide.md) integration, `none` disables it. When unset, no connector is configured. This flag is specific to TensorRT-LLM; other backends configure KV transfer through their own engine options.
+
+  <span className="enum-values"><span className="enum-label">Allowed values:</span> <Badge intent="note" minimal>kvbm</Badge> <Badge intent="note" minimal>none</Badge></span>
+
+  Environment variable: `DYN_CONNECTOR`
+</ParamField>
+
 ## Engine args passthrough
 
 <ParamField path="--extra-engine-args" type="string" default='""'>

docs/fern/pages/reference/backends/vllm-configuration.mdx

@@ -91,12 +91,6 @@ python -m dynamo.vllm \
 
 Only the prefill worker is required to set it, but both halves of a NIXL pair must agree on a connector for transfers to succeed. Pass the same `--kv-transfer-config` value to the decode worker, as the [disaggregated vLLM launch script](https://github.com/ai-dynamo/dynamo/blob/main/examples/backends/vllm/launch/disagg.sh) does.
 
-The earlier `--connector` flag is no longer accepted by the vLLM backend. Setting it — on the command line or through the `DYN_CONNECTOR` environment variable — raises a `ValueError` during argument parsing. The message depends on the value:
-
-- An active connector, such as `--connector nixl` or `DYN_CONNECTOR=nixl`, reports the equivalent `--kv-transfer-config` JSON to use instead.
-- `--connector none` or `--connector null` reports that the flag is no longer needed, because no connector is already the default. There is no equivalent value to migrate to, so none is shown.
-- `DYN_CONNECTOR` set to an empty or whitespace-only value reports that the variable is no longer supported, without an equivalent value.
-
 ## Worker role and disaggregation
 
 These flags control which role this worker plays in a disaggregated deployment. The default when no `--disaggregation-mode` is set is aggregated (`agg`).

docs/fern/pages/reference/components/runtime-configuration.mdx

@@ -132,12 +132,6 @@ Unless a field is marked environment-only, it has both a CLI flag and an environ
   Environment variable: `DYN_EVENT_PLANE`
 </ParamField>
 
-<ParamField path="--connector" type="string" default="null">
-  KV-cache transfer connector. Accepts zero or more values. Deprecated for vLLM — use `--kv-transfer-config` instead. For TRT-LLM, valid options are `nixl`, `lmcache`, `kvbm`, `null`, and `none`.
-
-  Environment variable: `DYN_CONNECTOR`
-</ParamField>
-
 ## Parsing
 
 <ParamField path="--dyn-tool-call-parser" type="string" default="null">

recipes/nemotron-3-super-fp8/README.md

@@ -140,10 +140,10 @@ These recipes target Dynamo v1.0.0. To run on v0.9.1 containers, the following c
 
 ### vLLM (`vllm-runtime:0.9.1`)
 - Change image tags from `:1.1.1` to `:0.9.1`
-- **Add** `--connector none` to worker args (required in 0.9.1 to disable nixl KV connector; rejected in 1.0)
 - Change `--dyn-reasoning-parser` from `nemotron_nano` to `deepseek_r1` (nemotron_nano reasoning parser is broken in 0.9.1)
 - `enable_thinking: false` will **not work** with `deepseek_r1` parser (response content goes to `reasoning_content`, `content` is null)
 - `--mamba-cache-mode align` is still needed (0.9.1 ships vLLM 0.14.1, also affected by [vllm#34865](https://github.com/vllm-project/vllm/issues/34865))
+- **Add** `--connector none` to worker args (required in 0.9.1 to disable nixl KV connector; rejected in 1.0)
 
 ### TensorRT-LLM (`tensorrtllm-runtime:0.9.1`)
 - Change image tags from `:1.1.1` to `:0.9.1`