- "Kør nu" (ServerRequestHandler) goes through SyntheticCheckService.RunNowAsync: it joins a
run of the check that is going on, or runs it under the same MaxParallelChecks throttle
and registers it, so it never overlaps a scheduled run. A paused check is not run: the
answer is "Tjekket er sat på pause." and nothing is stored, evaluated or opened.
- Server requests (test, run now) may take 3 min (the check's max timeout 120 s + the
30 s service lookup + 30 s margin) instead of AgentRequestService's 2 min, so the result
is always stored; a server test gets 2.5 min. Stale Running requests are cleaned after
the longest timeout + 1 min.
- An exception a check run did not foresee becomes a stored failed result ("Tjekket kunne
ikke køres: …"), so LastRunAt advances and the check waits its interval; it is logged
once per change. A run that cannot even be stored is not retried before its interval
(the agent remembers when it started it).
- The service lookup of a failing check has its own 30 s deadline; its error detail
(naming the agent's account) is Sensitive.
- The rules get max(10, FailuresBeforeFinding, SlowRunsBeforeFinding) + 1 recent results
(at most 100), so "Fejlet i træk" and FailuresBeforeFinding > 10 work.
- The interval is never under SyntheticCheckLimits.MinIntervalSeconds agent-side; state
for removed checks is pruned; shutdown waits for running checks before the throttle is
disposed; a TaskCanceledException that is not shutdown no longer ends the service.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
Deadlines
- Event log over RPC (MS-EVEN6): the whole read has a deadline (OperationTimeout per log);
the token cancels the EventLogSession's operations and is checked before each
FormatDescription, and the agent stops waiting even if the native call ignores it.
Reported as ServerAccessProblem.Timeout ("svarede ikke i tide over hændelsesloggens
protokol (RPC) inden for N sekunder").
- Every CIM call runs on the thread pool and is awaited with the caller's token; a call
that ignores cancellation is abandoned and the CIM session is closed once it returns.
- Each server cycle has a deadline (new SQLInsight:Servers:CycleTimeout, default 5 min,
1-30 min, at least 2 x OperationTimeout): the areas not read by then are "ikke målbar"
("Serveren svarede ikke inden for N minutter, så indsamlingen blev afbrudt; …"),
logged once, and the slot is freed.
- Scheduled tasks: run information is read within a time budget (CycleTimeout / 3); the
rest keep their state without the last run, and the coverage note says so.
- "Test server" has an overall deadline (WindowsServerTester, default 2 min); areas not
done in time are reported as not answered, so the result is always stored.
Backoff and memory
- A server that does not answer (Unreachable/Timeout, or a timed-out cycle) is backed
off 1, 2, 5, 10, then 15 minutes, reset when it answers.
- Protocol Auto: the protocol that worked (e.g. DCOM after WS-Man was refused, also for
access denied) is tried first for an hour, then WS-Man is tried again; a server whose
event log RPC failed is read over CIM for an hour.
- Over WS-Man with read-only WinRM rights Task Scheduler's GetInfoByName is denied: with
Auto the tasks are read over DCOM instead (remembered for the server); with WSMan forced
the reason says to choose Auto or DCOM. The advice "winrm configSDDL default" (broader
WinRM rights) is gone; texts follow the grant script (-WinRM read right,
-EnableFirewall -AgentAddress), not Remote Management Users.
Events
- Each log continues from its own mark (ServerEventSnapshot.LogReadUntil, a small additive
field in Core): a truncated System log no longer loses the events between its last
read event and the newest Application event.
- CIM fallback: Win32_NTLogEvent is streamed and only the oldest max per log are kept
(memory bounded, deterministic order), consistent with the RPC read and the coverage
text, which now names the logs that had more.
Other
- CimInstances (and method results) are mapped to SQLInsight's types and disposed at once.
- Options are clamped when bound (ServerOptions/SyntheticCheckOptions.Normalize):
OperationTimeout 5 s-5 min, MaxEventsPerCollection 10-10000, MaxWatched 1-200,
MaxParallelServers/Checks 1-32, retention days >= 1, ForecastHistoryDays 1-365,
FailuresBeforeFinding/SlowRunsBeforeFinding 1-99.
- Shutdown: the timer's cancellation is caught, running cycles are awaited before the
throttle is disposed; a cycle's time is taken when it gets its slot; a TaskCanceledException
that is not shutdown no longer ends the service.
- Retention maintenance also runs (hourly) when SQLInsight:Servers:Enabled is false but
synthetic checks are on.
- LocalCimTests run alone (collection without parallelization), share one warmed-up
session, use the same 2 min operation timeout and a 5 min deadline per test, a smaller
workload, and report timings in assertion messages.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
- ServerMonitoringService keeps the SQL Server hosts in step with the monitored
instances (SQLInsight:Servers:IncludeSqlHosts), picks up servers added, paused or
changed in SQLInsight Web within a minute, and runs each server's due areas with
a limit on parallelism. Default intervals: 1 min CPU/memory, 15 min disks and
tasks, 5 min services and events (SQLInsight:Servers:Intervals).
- ServerMonitor: one CIM session per cycle; per-minute samples, disk samples and
the "fuld om ca. N dage" forecast from the stored history, grouped events (read
from where the last read stopped), services and tasks. A missing right makes
only that area "ikke målbar" with the exact reason, logged once per change; a
server that does not answer is notified once, and again when it answers.
Survives an agent restart (samples, boot time, event position).
- SyntheticCheckService runs checks on their interval, opens a SQL login password
sealed for the agent (AgentCredentialKey.OpenContext), looks up the linked
Windows service when a check fails, stores results and findings, notifies with
links to /servere/fund/{id}.
- AgentRequestService hands ServerTest and SyntheticCheckRun to ServerRequestHandler.
- appsettings.json: SQLInsight:Servers and SQLInsight:SyntheticChecks with every
threshold, interval and retention.
Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>
