NEXT-07 is struck: windev was redeployed from origin/main (a346d51) and the service is
healthy, and the root cause the row predicted is confirmed -- the 2026-06-25 build's
Auth.ApiKeys 0.1.2.0 supports auth-DB schema 2 while the database sits at schema 3, which
is the current shared-lib version, so deploying forward was the fix rather than touching
the DB. The original text stays for the triage record.
Three findings surfaced by that work, each deliberately left for the next cycle rather
than patched in passing:
- NEXT-08: the shared GLAuth offers no TLS, so SEC-06 makes GatewayConfiguration.md's
"deployed hosts must set Ldaps or StartTls" unsatisfiable for anything genuinely
labelled Production. windev's relabel to Staging is honest for a dev rig but defers
the posture question rather than answering it.
- NEXT-09: Directory.Build.props:29 quotes a path ending in a backslash, so the SHA-stamp
git invocation is malformed on Windows and ContinueOnError stamps git's stderr into
InformationalVersion -- a Windows binary cannot be correlated to a commit, which is what
TST-11 exists to guarantee.
- NEXT-10: glauth.md's pre-provisioned-user table contradicts both the directory and its
own dashboard section, and was the root cause of the NEXT-06 fixture drift. Reconciling
it sweeps the OPC-UA group taxonomy, so it is scoped out here on purpose.
The TST-30 runner work is hygiene, not closure: runner-1 now mounts its registration token
from a 0600 file like runner-2, but both still share one instance-scope token that was
world-readable for months and is provably still live. Gitea 1.26.4 cannot rotate it from
the CLI or API, so the UI reset is recorded as a pending operator action with its
follow-through (refresh the token file, shred the token-bearing compose backups).
SEC-36's primary check -- dashboard /login through the real DashboardAuthenticator
search bind -- was deferred because windev's gateway was crash-looping on the stale
deployment filed as NEXT-07. That host was redeployed 2026-08-07, so the check ran:
login as multi-role returns 302 with the dashboard cookie and the authenticated page
renders the admin nav, while an anonymous control still redirects to /login. The
rotated service-account credential is now proven end-to-end on the deployed host, not
only by the equivalent ldapsearch primitive, and the runbook's Correction 3 is past
tense throughout rather than describing a fault that no longer exists.
Also record why windev runs the Staging environment name. The redeploy tripped SEC-06's
Production hard-stop on Ldap:Transport=None, and windev cannot satisfy it: it binds the
shared GLAuth, which offers no TLS, and runs Dashboard:DisableLogin=true. The Production
label contradicted its own configuration, so the host was relabelled rather than the
guard weakened -- exactly the permissive-staging-rig case the SEC-35 section already
carves out.
The suite's fixtures had drifted from the shared GLAuth config, so a green run
proved nothing about the service-account bind: the only success-path test used
admin/admin123, but the directory's admin carries the standard dev password, and
the "not an admin" test used a readonly user that does not exist there at all --
it passed via the user-not-found branch rather than the group-missing branch it
names.
Realign to real users from scadaproj/infra/glauth/config.toml: admin/password
(othergroups include GwAdmin, gid 5610) for the success path, and
gw-viewer/password (GwReader only, gid 5611) for the bind-succeeds-but-no-role
path. Both are published dev credentials documented in glauth.md, not secrets.
The gw-viewer test drops its old no-leak assertion on the credential literal:
the real password is the word "password", which legitimately occurs in the
generic denial text, so the check would fail for the wrong reason. The no-leak
property is still covered with a distinctive literal by the wrong-password test.
In its place the test now asserts the property this fixture is uniquely able to
prove -- an authorization failure must be reported with the same message as an
authentication failure, so it cannot be used to enumerate valid accounts.
appsettings ships Server=localhost, so document the MxGateway__Ldap__Server
override the suite needs to reach the shared GLAuth alongside the existing
MXGATEWAY_RUN_LIVE_LDAP_TESTS and ServiceAccountPassword variables.
Verified live: Failed: 0, Passed: 5 against 10.100.0.35:3893.
The local act_runner on this Mac registered as instance runner id 4 with
ubuntu-latest/22.04/20.04 labels, so it competed with the two docker
runners on 10.100.0.35 for Linux jobs it had no Docker daemon to run --
13 of the last 20-run window in historiangw landed on it and all but one
failed. Registration deleted; local config kept disabled for re-use with
mac-specific labels.
The blanket loop asserted HRESULT/Statuses/ReturnValue on every command_replies fixture, but the authenticate-user.* fixtures added for the malformed-reply and credential-redaction contracts deliberately omit them (NRE on ReturnValue.DataType). Keep universal Kind/ProtocolStatus invariants for all; apply the MXAccess-detail block only to fixtures that carry it. Test-only.
Code review of the CLI-39 branch caught an Important gap: Contracts.csproj
was left at the already-published 0.1.2 while the .NET Client moved to
0.2.0. Invoke-PackDotnet in scripts/pack-clients.ps1 packs and publishes
both ZB.MOM.WW.MxGateway.Contracts and .Client through the same -Publish
loop, and the new collision guard runs every nupkg it finds through
Assert-GiteaPackageNotPublished. Left as-is, the next real .NET publish
would pack Contracts at 0.1.2, the guard would correctly refuse to
republish it, and the loop would abort mid-way with Client (alphabetically
first) possibly already pushed -- the two packages permanently out of
lockstep.
- src/ZB.MOM.WW.MxGateway.Contracts/ZB.MOM.WW.MxGateway.Contracts.csproj:
<Version> 0.1.2 -> 0.2.0, matching the .NET Client (they have always
released together).
- src/Directory.Build.props: corrected a comment that was now stale --
it claimed the repo-wide 0.1.2 default was kept to match the Contracts
package, which is no longer true now that Contracts.csproj overrides it.
The <Version> value itself is unchanged; Server/Worker/Tests staying at
0.1.2 is a separate, not-yet-made decision, out of scope for CLI-39.
- docs/ClientPackaging.md: Contracts.csproj added as a fifth manifest in
the Versioning section, with the near-miss recorded.
Also hardened scripts/pack-clients.ps1 per the same review: the Python
(pyproject.toml) and Rust (Cargo.toml) version-extraction regexes now
scope to the [project]/[package] section header instead of matching the
first "version = ..." line anywhere in the file (Cargo.toml has an
identical second one under [workspace.package] -- matching whichever came
first was luck of ordering, not correctness). One-line comment added on
the nuget filename-parse regex.
Verified live against the real Gitea registry: Contracts and Client both
still refuse at 0.1.2 and both now pass at 0.2.0, including running the
actual Invoke-PackDotnet filename-parse-then-guard logic against two
freshly packed real .nupkg files. dotnet build of Contracts.csproj and the
client slnx both clean. No publish performed.
Converges all five clients on one version after four had drifted onto the
already-published 0.1.2/0.1.1 while their APIs kept changing underneath it:
- Rust Cargo.toml [package] + [workspace.package] -> 0.2.0 (CLIENT_VERSION
already derives from CARGO_PKG_VERSION, no separate edit).
- Python pyproject.toml + version.py -> 0.2.0; new test asserts __version__
matches pyproject.toml (closes the CLI-26 residual drift mode).
- Go mxgateway/version.go ClientVersion -> 0.2.0.
- .NET ZB.MOM.WW.MxGateway.Client.csproj <Version> -> 0.2.0.
- Java -> 0.2.1, not 0.2.0: the live Gitea Maven feed already had 0.2.0
published (2026-06-26), before the CLI-37/38/40/41 conformance fixes
changed the client's observable behavior, so reusing 0.2.0 would label
two different APIs identically. Recorded as an exception in
docs/ClientPackaging.md's new Versioning section.
Publish-pipeline guards:
- scripts/tag-go-module.ps1 implements the CLI-21 guard: after semver
validation it refuses to tag unless clients/go/mxgateway/version.go's
ClientVersion already matches the requested tag version.
- scripts/pack-clients.ps1 gains a Gitea package-registry collision guard
wired into every per-language -Publish step; it aborts if the target
name+version already exists rather than force-overwriting. Verified live
against the real Gitea registry (credentials already present in this
environment) — correctly refuses on every known-published artifact and
passes on every unpublished target.
Docs updated in the same commit: docs/ClientPackaging.md (new Versioning
section), and the five client READMEs' stale 0.1.1/0.1.2 example versions.
No .proto changes. No publish performed.
WRK-22/IPC-26: tombstone a WriteAsync/WriteBatchAsync cancelled while
waiting for the write lock (PendingFrame.Claimed under _gate; DequeueNext
skips cancelled, claims the frame it returns) so a cancelled write never
reaches the wire unless already claimed mid-write (documented residual).
WRK-25: add WriteBatchAsync; RunEventDrainLoopAsync submits the drained
event batch through it, so a burst of N events costs one flush not N.
IPC-30 oversized-event structured fault preserved via FindOversizedEvent.
WRK-24: reject a below-1024 negotiated frame maximum at the handshake
(MinNegotiableFrameBytes, matching GatewayOptionsValidator floor).
WRK-27: alarm poll advertises StaCallInProgress on the heartbeat snapshot
so the watchdog suppresses to the ceiling, not the grace.
Docs (WorkerFrameProtocol.md, MxAccessWorkerInstanceDesign.md) and the
2026-07-12 remediation registers/change-log updated in the same commit.
Doc half of TST-30 (single shared Gitea runner is a CI throughput/availability
bottleneck): docs/GatewayTesting.md's Continuous Integration section gains a
"Runner capacity is shared and finite" subsection covering the maxParallel=1
instance-level runner shared with dohertj2/lmxopcua, the ~20-30 min queue
latency observed under cross-repo contention, and Gitea 1.26's missing run
cancel/delete API. The existing "windev tier down" degraded-mode paragraph now
also covers "runner contended" as a reason to bypass the queue via
CI_SHA=<sha> scripts/ci/run-windev-ci.sh <mode> or the manual windev worktree
flow, generalizing it per the finding's design note.
New operator runbook docs/runbooks/TST-30-second-ci-runner.md carries the
actual runner registration (option a: second act_runner instance on
10.100.0.35 with the same container.network: traefik config, recommended;
option b: dedicated labelled runner, escalation only; option c: runner on
windev, rejected) plus verification steps and the no-cancel caveat. The
optional workflow-level concurrency group is documented as unverified --
framed as "verify before relying on it" -- and left unimplemented in ci.yml,
since registering the runner and any runs-on gating is operator/infra work
outside this repo's tree.
Tracking: TST-30 -> Done (doc half; runner registration operator-pending) in
both registers + change-log row.
ClientProtoInputTests.Descriptor_ContainsEveryContractMessageAndField only
compared messages and fields, and only enumerated the gateway/worker
descriptors, so a new enum value, a new RPC, or any galaxy_repository.proto-only
change would not redden the test even though it is documented as the primary
protoc-free CI gate.
Rename to Descriptor_ContainsEveryContractSymbol and extend the reflection walk
on both sides (published protoset and in-process contract) to also collect
enums/enum values ({enumFullName}, {enumFullName}/{valueName}) and
services/methods ({serviceFullName}, {serviceFullName}/{methodName}), and add
GalaxyRepositoryReflection.Descriptor to the enumerated files. The comparison
stays a flat, order-insensitive string-set diff with no protoc dependency.
Update docs/ClientProtoGeneration.md and docs/Contracts.md prose from
"message or field" to the full symbol coverage.
Red-path proof: pointed the test at the pre-IPC-01 stale protoset and confirmed
it failed naming max_frame_bytes, several MxCommandKind/AlarmProviderMode enum
values, MxAccessGateway/StreamAlarms and GalaxyRepository/BrowseChildren, and
the galaxy_repository.v1.* surface; restored the real path and re-ran green.
Flips IPC-27 to Done in the 2026-07-12 remediation tracker and register.
Proto comments (comment-only, no wire change):
- mxaccess_worker.proto GatewayHello.max_frame_bytes: every worker->gateway frame
must serialize within the negotiated max; reply builders truncate (IPC-23).
- mxaccess_gateway.proto DrainEventsReply: count-cap + byte-cap, drain-until-empty
caller contract (IPC-23).
- mxaccess_gateway.proto ReplayGap.oldest_available_sequence: empty-ring value is
highest-observed+1, oldest-1 resume formula stays valid (GWC-25 deferred amendment).
Regen wave: Contracts/Generated (C# XML doc), rust vendored protos (byte-copy),
Go bindings (worker binding was genuinely stale - lacked MaxFrameBytes entirely),
Python worker _pb2 (real descriptor delta), Java aggregates (javadoc, zero
protobuf-version churn under the pinned toolchain), client descriptor set.
IPC-24: pinned Java toolchain regenerates with no gencode-version churn, so the
unconditional churn-revert step in ci.yml is a fossil - deleted it; git diff is
now a true message-level drift gate for the single-file Java aggregates.
IPC-25: pin protoc-gen-go v1.36.11 / protoc-gen-go-grpc 1.6.2 in the Go generate
script (+ fix a latent pwsh-7 parse bug); add Check 4 to check-codegen.ps1
(regenerate Go+Python bindings, fail on diff, tool-missing fails not skips); add
the pinned-generator installs to the portable CI job.
IPC-32: relabel check-codegen banners 1/4..4/4 (folded into the Check 4 edit).
Docs: ClientProtoGeneration.md, Contracts.md, GatewayTesting.md, build.gradle
checkGeneratedClean caveat. Tracking: IPC-23/24/25/32 -> Done, GWC-25 proto note
resolved, change-log 2026-08-07.
Repo-side half of SEC-36. The appsettings.json plaintext was already discharged
before this branch (HEAD ships the fail-closed ${secret:ldap/mxgateway/bind}
store reference), so the residual leak was the literal value in glauth.md,
docs/GatewayTesting.md, and the historical archreview SEC-06 evidence -- all
scrubbed to <service-account-password> placeholders pointing at the source of
truth scadaproj/infra/glauth/.
- csproj: add <UserSecretsId>mxaccessgw-server</UserSecretsId> (dev channel)
- GatewayOptionsValidator: blank-password message now names both channels
(dev user-secrets, deployed MxGateway__Ldap__ServiceAccountPassword)
- test: assert the message names both channels
- docs: GatewayConfiguration.md (three channels + rotation note), glauth.md
(placeholders + rotation-required + runbook pointer), GatewayTesting.md
- new operator runbook docs/runbooks/SEC-36-ldap-credential-rotation.md
(live rotation + NSSM staging remain operator-pending)
- tracking: SEC-36 -> Done (repo-side) in both registers + change-log
Deviation: kept the ${secret:} reference in appsettings.json rather than
deleting it (spec step 2 assumed the stale plaintext baseline); deleting it
would regress the shipped/documented/tested secret-store channel.
git grep -i for the old value is empty across all tracked files.
TST-27: docs/GatewayConfiguration.md's ShowTagValues row no longer says
"Reserved" — it now states what false (default) does (DashboardEventBroadcaster
blanks tag values from a deep-cloned MxEvent before the SignalR events-hub
mirror), the security relevance (no per-session hub ACL yet, so this
redaction is the only thing between a low-trust Viewer and other sessions'
tag values), and the honest scope limit (does not cover /browse).
WRK-26 (discharges IPC-29): docs/MxAccessWorkerInstanceDesign.md's "Outbound
Queues" section rewritten from the stale five-level priority list to the
two-class Control/Event scheduler actually shipped, with the collapsed-
decision rationale, and the overflow paragraph rewritten to the implemented
fail-fast. docs/WorkerFrameProtocol.md gained a "Write Scheduling And
Sequencing" section describing HEAD truthfully: WRK-23's peek-stamp-commit
sequencing is live, WRK-25's event-batch flush coalescing is not (the drain
loop still awaits each event write individually), and WRK-22's cancellation
tombstone is not yet defined (noted as pending, not documented as shipped).
CLI-42: clients/rust/README.md and docs/ClientPackaging.md document the
vendored Rust proto layout matching build.rs — repo-path-first resolution
falling back to clients/rust/protos/, the check-codegen.ps1 Check 3 refresh
rule, and why cargo package/publish run without --no-verify.
CLI-43: docs/style-guides/JavaStyleGuide.md now says Java 17 (Ignition 8.3
baseline), mirroring CLI-12's wording, matching the shipped build.gradle.
IPC-28: docs/Grpc.md's exception-mapping prose gained CommandTooLarge ->
ResourceExhausted, and the Invoke section gained the oversized-payload
sentence, cross-referencing GatewayConfiguration.md's headroom rule.
Tracking: TST-27, WRK-26, CLI-42, CLI-43, IPC-28 flipped to Done and IPC-29
marked discharged-by-WRK-26 in 00-tracking.md and the 20/30/50/60 domain
registers, with a 2026-08-07 change-log entry.
Doc-only change; no source, proto, or test edits.
Review follow-ups on the WRK-21 cluster.
1. ResolveDrainReplyByteBudget was a step function, not a floor: just above the
64 KiB reserve the budget collapsed to a few bytes (at the validator-permitted
floor MaxMessageBytes = 1024 + 64 KiB it was exactly 1024), too small to move a
byte-heavy event, so DrainEvents truncated on every call and the drain-until-
empty loop never terminated. It now takes the max of (frameMax - reserve) and
frameMax/2, so the budget is monotonic and never below half the frame max. New
test DrainEvents_AtValidatorFloorFrameMax_MakesProgressAndTerminates drives a
byte-heavy queue at the exact validator floor and asserts it drains to empty
with no head ever reported oversized.
2. The reply-too-large fallback write is now itself size-guarded
(WriteReplyTooLargeFallbackAsync, used by both the control and STA reply seams):
at a pathologically tiny negotiated max below the gateway's floor the fallback
could also throw MessageTooLarge and — uncaught — kill the session, defeating the
"no diagnostics command is session-fatal" invariant. It now log-and-swallows;
comment notes WRK-24 adds the negotiated-max lower bound that makes it unreachable.
3. Corrected the RepeatedFieldOverheadBytes doc comments: WorkerEvent.CalculateSize()
already includes the event's tag and length prefix (the same shape the reply's
repeated events field packs), so the 8 bytes is pure slack over an already-
conservative estimate, not compensation for a missing wrapper.
Code-review follow-up on the CLI-40/41/44 branch.
ISSUE 1 (all five, critical): the message-only scrub still leaked the
server-echoed credential through the redacted error's structured reply accessor
(.NET Reply/Statuses, Java reply()/protocolStatus(), Go MxAccessError.Reply via
errors.As, Rust reply()/into_reply(), Python raw_reply). The redacted error now
carries a scrubbed clone of the reply (protocol_status.message,
diagnostic_message, statuses[].diagnostic_text), with per-language tests asserting
the reply accessor no longer contains the credential.
ISSUE 2 (Rust, critical): ensure_command_success routed MXACCESS_FAILURE to
Error::Command (unlike the other four clients), bypassing attach_secrets and
leaking via derived Debug/Display. MXACCESS_FAILURE now routes to Error::MxAccess,
fixing the cross-client inconsistency.
ISSUE 3 (Go, important): the CLI-44 terminal send was unconditionally
non-blocking, dropping a genuine terminal error under a full buffer on the
never-drop SubscribeEvents path. It is now reserved-slot-non-blocking only for the
cancel-on-overflow path and blocking for the never-drop path.
New shared fixture authenticate-user.echoed-credential-mxaccess-failure.reply.json
wired into all five suites. Minors: whitespace-secret guard on .NET/Java redact
helpers; Java preserves exception subtype on redaction; redaction-helper unit
tests (Go/Java/.NET). Docs (ClientBehaviorFixtures.md, ClientLibrariesDesign.md)
updated to make the structured-field claim true.
Change-log row for 2026-08-07: what landed for WRK-21/WRK-28/WRK-23/IPC-30, why
IPC-23 stays In progress (proto-comment/doc wave pending), and the verification
evidence — macOS NonWindows build + validator tests, and the documented windev
path (scripts/ci/windev-worker-ci.ps1 -Mode test) at a256560: x86 Worker build
clean, Worker.Tests 367 passed / 0 failed / 11 skipped.
PipePair runs both ends of a duplex pipe in one process with blocking
FlushFileBuffers under every frame write, so it wedges after roughly 85 large
round trips. Drain the full 10,000 byte-heavy events to empty at the queue layer,
where the no-loss property actually lives, and keep the pipe walk at 1,000 events
(29 replies) so it still proves the split end to end. Also give the truncation
test's budget slack: item handle 0 is a proto3 default and is not serialized, so
the probe measurement is a lower bound on the fixture's per-event cost.
Same-commit docs rule (were missed in the prior commit):
- docs/GalaxyRepository.md: SnapshotCachePath now documents the per-OS derived
default and the GalaxyRepositoryOptionsValidator rooting/validity enforcement.
- A2-galaxyrepository-adoption-handoff.md: correct the now-inaccurate NSSM caveat
(SnapshotCachePath override is optional, not required; blank seeds a rooted host
default, no silent no-op) and repoint the option-validation item at the new
GalaxyRepositoryOptionsValidator.
SEC-34 guard confirmed and documented: TryParseKeyId's '_' split cannot truncate a
key id because both — and the only — gateway key-creation paths
(ApiKeyAdminCommandLineParser.IsValidKeyId, DashboardApiKeyManagementService.ValidateKeyId)
restrict key ids to IsAsciiLetterOrDigit || '.' || '-', and key ids are never
library-generated. Added a citing comment; no behavior change.
Test consolidation: moved the three host-start SqlitePath overrides into
TestHostEnvironmentInitializer (per-process temp store, mirroring Secrets__SqlitePath)
so future host-start tests auto-cover.
CLI-40: port the exact-secret credential scrub to Rust/Java/.NET (Go/Python
already did it). AuthenticateUser/WriteSecured(2) helpers now redact the exact
caller-supplied secret from any surfaced error, as defense-in-depth on top of the
by-construction guarantee. Rust hand-writes a redacting Debug (derived Debug would
leak the reply); Java/.NET rebuild the same exception type with the redacted
message and do not carry the secret-bearing original forward (so ToString/stack
traces stay clean too).
CLI-41: uniform malformed-reply contract for AuthenticateUser/ArchestrAUserToId/
AddBufferedItem across all five clients — typed payload, else a present int32
return_value, else a typed malformed-reply error. Fixes Go/Java silent-0, .NET
NRE, and Rust's own internal inconsistency.
CLI-44: the Go event goroutine's Recv-error path now uses a non-blocking
sendTerminalEventResult on the reserved slot, so a genuine terminal stream error
is reported as itself instead of being mislabeled ErrSlowConsumer under overflow.
Riders from the CLI-37/38 review: (a) .NET ToDiagnosticSummary and Python
_mxaccess_message surface the raw success member (diagnostics-only parity with
Rust); (b) the status-conversion fixture carries an independent wantSuccess
boolean and the Go/.NET fixture tests assert against it instead of recomputing
the formula under test.
Shared fixtures (authenticate-user.{echoed-credential,missing-payload,
return-value-only}.reply.json) + manifest + ClientBehaviorFixtures.md +
ClientLibrariesDesign.md updated in the same change. Tracking: CLI-40/41/44 -> Done.
SEC-33: make rooting host-meaningful and stop shipping foreign-platform literals.
- Delete IsRootedForAnyPlatform; AddIfNotRooted now uses Path.IsPathRooted (current OS).
- Promote AddIfNotRooted/AddIfInvalidPath to shared GatewayConfigPathRules so the new
Galaxy validator reuses them and the two validators cannot drift.
- Remove Authentication:SqlitePath and Galaxy:SnapshotCachePath Windows literals from
appsettings.json; the CommonApplicationData-derived code defaults take over. The
Galaxy default is seeded as a configuration value before AddZbGalaxyRepository
(SnapshotCachePath is init-only, so a PostConfigure mutation cannot compile).
- New GalaxyRepositoryOptionsValidator (ValidateOnStart) enforces a valid, host-rooted
SnapshotCachePath when PersistSnapshot is true.
- Root-cause the stray junk-named auth DB: host start eagerly builds
AuthSqliteConnectionFactory; under the non-rooted Windows literal on macOS SQLite
wrote it relative to the test bin CWD. The three real-host-start tests now pin
SqlitePath to a temp path.
SEC-34: verification cache Invalidate-vs-in-flight-repopulation race closed with a
per-key generation counter (bump-before-evict, snapshot-then-recheck). The expiry
cap (window 2) takes the documented fallback: the library verification identity
carries no ExpiresUtc, so the cache cannot cap at the key's expiry (donor-library ask).
GWC-24 rider: cap MxGateway:Events:QueueCapacity at int.MaxValue/2 so the derived
checked(2 * EventChannelCapacity) in WorkerClient cannot overflow at session creation.
SEC-35 (doc-only): note IsProduction() env-name semantics in GatewayConfiguration.md.
Docs updated same commit (GatewayConfiguration.md, Authentication.md) and tracking
registers/change-log flipped (00-tracking.md, 40-security-dashboard.md).
PipePair has no continuous read pump — the test thread drains the pipe only
while it sits in ReadUntilAsync — so multi-megabyte DrainEvents frames
interleaved with the heartbeat loop wedge both ends inside FlushFileBuffers,
each waiting for the other to read. Negotiate a 128 KiB frame maximum instead:
the 10,000 byte-heavy events still overflow it many times over, so every
assertion (bounded reply, reported truncation, no event loss across repeated
drains, surviving session) is unchanged.
Joseph Doherty