[ddmd] add --no-state-machine flag for test fixtures and Linux build#729
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Omicron's oxidecomputer/omicron#10381 introduces a stubbed `ddmd` admin endpoint because spawning a real `ddmd` in a generic test toolchain is not viable: the routing state machine (discovery, exchange, route synchronization) depends on illumos networking facilities the toolchain does not provide. Consumers of the stub, e.g., Nexus RPW (multicast members), sled-agent's DDM reconciler, and anything that resolves the DDM internal-DNS service name, cannot exercise the real admin surface from Omicron's test harness. This work adds an opt-in `--no-state-machine` flag to `ddmd` that runs only the admin API server and skips the state machine entirely, allowing the fixture to spawn the real binary. This is analogous to `mgd --no-bgp-dispatcher`, which Omicron's `MgdInstance` already uses for the same purpose. To make the fixture path usable on Linux, `ddmd` itself must build on Linux. The previous code pulled the illumos-only crates `libnet`, `dpd-client`, `opte-ioctl`, and `oxide-vpc` unconditionally through `ddm`, which failed to link on Linux (`-lzfs`, `-ldlpi`). This change introduces an `illumos` feature in both `ddm` and `ddmd` (default-on, mirroring `mgd`'s `mg-lower` pattern) that marks those four crates optional. The buildomat `linux.sh` job now builds `ddmd` and `ddmadm`, with `ddmd` invoked as `cargo build --bin ddmd --no-default-features`. The illumos-only halves of `ddm` are isolated by the feature gate: - The routing state machine implementation moves from `sm.rs` into `sm/state.rs`. - The exchange runtime (HTTP push/pull and route programming) moves from `exchange.rs` into `exchange/runtime.rs`. - The discovery runtime (UDPv6 solicitation/advertisement loops) moves from `discovery.rs` into `discovery/runtime.rs`. Each parent `mod.rs` keeps the platform-agnostic types and re-exports the runtime surface so existing call sites resolve unchanged on illumos. The runtime submodules are gated as a unit by `#[cfg(all(feature = "illumos", target_os = "illumos"))]`. We also remove the single-function `ddm/src/util.rs`, inlining the function into `discovery/runtime.rs`, where its sole caller lives. The SIGTERM cleanup handler is installed regardless of the flag, so Ctrl-C still exits cleanly in `--no-state-machine` mode. The imported route sets are empty in that mode, so the cleanup itself is a noop. Passing `--addr` alongside `--no-state-machine` is harmless but ignored, with a warning logged.
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…fixture We address @jgallagher's review by: - Replacing the four positional `u16` arguments in `DnsConfigBuilder::host_zone_switch` with a `HostSwitchZonePorts` named-fields structure. - Replacing the dropshot-based stubbed `DdmInstance` in test-utils with a fixture that spawns and supervises a real `ddmd` subprocess running with `--no-state-machine`, analogous to `MgdInstance` and `mgd --no-bgp-dispatcher`. Only the switch-zone `ddmd` is registered in internal DNS, while sled-global-zone instances are accessed locally by their own host and don't need DNS registration. This **does** require maghemite changes, already PR'ed to oxidecomputer/maghemite#729. To make this all work, we wire `ddmd` into the developer xtask toolchain. `cargo xtask download maghemite-ddmd` reuses the existing `mg-ddm.tar.gz` illumos zone artifact (extracting `ddmd`/`ddmadm`). On Linux it overlays a raw `ddmd` binary, and on macOS it builds from source. Also, we had to bump `oxnet` from 0.1.4 to 0.1.5 to satisfy the new maghemite pin.
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Just a few notes on the mechanics of the split; I'll defer to folks who know maghemite better for the code organization.
Includes: - Reject `--no-state-machine` together with `--addr` at clap level via `conflicts_with` - Collapse the two cfg-gated `termination_handler` variants into one cfg-gated body. - Rename the `illumos` Cargo feature to `state-machine` so that it describes the gated functionality (and matches the CLI flag) rather than colliding semantically with `target_os = "illumos"`.
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Omicron's oxidecomputer/omicron#10381 introduces a stubbed
ddmdadmin endpoint because spawning a realddmdin a generic test toolchain is not viable: the routing state machine (discovery, exchange, route synchronization) depends on illumos networking facilities the toolchain does not provide. Consumers of the stub, e.g., Nexus RPW (multicast members), sled-agent's DDM reconciler, and anything that resolves the DDM internal-DNS service name, cannot exercise the real admin surface from Omicron's test harness.This work adds an opt-in
--no-state-machineflag toddmdthat runs only the admin API server and skips the state machine entirely, allowing the fixture to spawn the real binary. This is analogous tomgd --no-bgp-dispatcher, which Omicron'sMgdInstancealready uses for the same purpose.To make the fixture path usable on Linux,
ddmditself must build on Linux. The previous code pulled the illumos-only crateslibnet,dpd-client,opte-ioctl, andoxide-vpcunconditionally throughddm, which failed to link on Linux (-lzfs,-ldlpi). This change introduces anillumosfeature in bothddmandddmd(default-on, mirroringmgd'smg-lowerpattern) that marks those four crates optional. The buildomatlinux.shjob now buildsddmdandddmadm, withddmdinvoked ascargo build --bin ddmd --no-default-features.The illumos-only halves of
ddmare isolated by the feature gate:sm.rsintosm/state.rs.exchange.rsintoexchange/runtime.rs.discovery.rsintodiscovery/runtime.rs.Each parent
mod.rskeeps the platform-agnostic types and re-exports the runtime surface so existing call sites resolve unchanged on illumos. The runtime submodules are gated as a unit by#[cfg(all(feature = "illumos", target_os = "illumos"))]. We also remove the single-functionddm/src/util.rs, inlining the function intodiscovery/runtime.rs, where its sole caller lives.The SIGTERM cleanup handler is installed regardless of the flag, so Ctrl-C still exits cleanly in
--no-state-machinemode. The imported route sets are empty in that mode, so the cleanup itself is a noop. Passing--addralongside--no-state-machineis harmless but ignored, with a warning logged.