The unattended alternative.

Before the first run.

• Run as Administrator — the script aborts otherwise.
• dbatools and sqmSQLTool reachable (share → local → PSGallery, as configured in settings.ini).
• Installation media under <InstallDrive>:\SQLSources\SQL<Version>\SQL_Install (plus \Reporting, \Management, \TDP for optional components) — same as the GUI.
• For AlwaysOn: an existing WSFC, run from a cluster node, with the FailoverClusters module.

Always dry-run first.

:: via the .cmd launcher (checks elevation, forwards all arguments)
Start-SqlSetup.cmd -Version 2022 -Edition Developer -NonInteractive

:: or directly with PowerShell
powershell.exe -NoProfile -ExecutionPolicy Bypass -File .\Start-SqlSetup.ps1 -Version 2022 -NonInteractive

Dry run (recommended before every real run):

Start-SqlSetup.cmd -Version 2025 -Edition Developer-Standard -InstanceName SQL01 -WhatIf

-WhatIf resolves the configuration and paths, prints the installation plan, and runs nothing.

Every parameter, one table.

Note on PreInstall: Invoke-PreInstallChecks (64K format / snapshot / HPU) uses interactive dialogs and is therefore skipped automatically under -NonInteractive. Run interactively, without -NonInteractive, to get these checks.

Nine steps, identical to the GUI.

1. Admin checkImport modules (identical to Main.ps1).
2. Resolve configurationGet-SetupConfig (settings.ini + domain profile) — CLI parameters override individual values.
3. Dependency checkAssert-DbaToolsReady / Assert-sqmSQLToolReady.
4. Resolve pathsGet-SqlPaths prints the plan (with -WhatIf, this is where it stops).
5. PreInstall checksOptional, interactive only.
6. InstallNew-SqlDirectories → Invoke-SqlInstallation (= Install-DbaInstance).
7. Components & driversOptional components (SSAS/SSRS/TDP/SSMS) and drivers (JDBC/ODBC/DB2).
8. PostInstallInvoke-PostInstall (memory/TempDB/ports/monitoring/Ola/...).
9. AlwaysOnIf -AlwaysOn: Invoke-sqmAlwaysOnSetup.

SSIS belongs to the engine feature (IS). If SSIS isn't listed in -Component, the CLI removes IS from the feature list — exactly like unchecking the GUI checkbox.

Full availability-group creation.

-AlwaysOn calls Invoke-sqmAlwaysOnSetup (module sqmSQLTool), which reads the WSFC and nodes, detects the listener role if not given, checks connectivity (Windows Auth/Kerberos preferred, falling back to -SqlCredential if SPNs are missing), optionally backs up the cluster settings, creates the availability group with automatic seeding, joins secondaries, syncs logins, and can emit an SPN request file for the AD team. Both functions are fully -WhatIf-capable.

AlwaysOn directly, without an install:

Import-Module sqmSQLTool
# Full run on the cluster node:
Invoke-sqmAlwaysOnSetup -AvailabilityGroupName ProdAG -Database AppDb

# Dry run with SQL auth:
Invoke-sqmAlwaysOnSetup -AvailabilityGroupName ProdAG -Database AppDb -SqlCredential (Get-Credential sa) -WhatIf

# Just the AG core creation, fully parameter-driven:
New-sqmAvailabilityGroup -SqlInstance SQL01 -SecondaryReplica SQL02,SQL03 `
    -AvailabilityGroupName ProdAG -Database AppDb `
    -ListenerName ProdAGL -ListenerIPAddress 10.0.0.50 -ListenerPort 1433 `
    -ServiceAccount 'CONTOSO\svcSql'

Three real invocations.

:: Unattended default instance, SQL 2022 Developer
Start-SqlSetup.cmd -Version 2022 -Edition Developer -NonInteractive

:: Named instance, SQL 2025, SSMS+SSIS only, ODBC driver, dry run
Start-SqlSetup.cmd -Version 2025 -Edition Developer-Standard -InstanceName SQL01 -Component SSMS,SSIS -Driver ODBC -WhatIf

:: Install + PostInstall + AlwaysOn AG
Start-SqlSetup.cmd -Version 2022 -NonInteractive -AlwaysOn -AvailabilityGroupName ProdAG -AgDatabase AppDb

How to know it actually worked.

• Dry run: -WhatIf resolves configuration, paths, and the planned steps without running them. Add -ProgressReport for a replay of the planned run.
• Lab VM: unattended install on 2019/2022, then Get-sqmSQLInstanceCheck green and a PostInstall report generated. Verify SQL 2025 separately.
• AlwaysOn: a 2–3-node WSFC lab → Invoke-sqmAlwaysOnSetup → Get-sqmAlwaysOnHealthReport shows a healthy AG and listener.
• Pester: Invoke-Pester against tests\Unit\Public\New-sqmAvailabilityGroup.Tests.ps1 (15 tests, mocked).

Where to look when something's off.

Log: every CLI run writes SqlSetupCli_<timestamp>.log to -LogPath (default C:\System\WinSrvLog\MSSQL). PostInstall and AlwaysOn steps additionally log via Invoke-sqmLogging. With -ProgressReport, an event stream (.events.jsonl) and the animated replay (.html) are written alongside it.

"Share not reachable": not fatal — the tool falls back to a local install / PSGallery; only the affected sources or features are skipped.
AlwaysOn connection fails: check SPNs (see the generated AD-team file), or pass -SqlCredential for SQL authentication.
Repeatability: every step is idempotent — running it again skips whatever already exists (instance, endpoint, AG, listener).