functions/Test-DbaConnection.ps1

#ValidationTags#Messaging,FlowControl,Pipeline,CodeStyle#

function Test-DbaConnection {
    <#
        .SYNOPSIS
            Tests the connection to a single instance.
 
        .DESCRIPTION
            Tests the ability to connect to an SQL Server instance outputting information about the server and instance.
 
        .PARAMETER SqlInstance
            The SQL Server Instance to test connection
 
        .PARAMETER Credential
            Credential object used to connect to the Computer as a different user
 
        .PARAMETER SqlCredential
            Login to the target instance using alternative credentials. Windows and SQL Authentication supported. Accepts credential objects (Get-Credential)
 
        .PARAMETER EnableException
            By default, when something goes wrong we try to catch it, interpret it and give you a friendly warning message.
            This avoids overwhelming you with "sea of red" exceptions, but is inconvenient because it basically disables advanced scripting.
            Using this switch turns this "nice by default" feature off and enables you to catch exceptions with your own try/catch.
 
        .EXAMPLE
            Test-DbaConnection SQL2016
 
            ComputerName : SQL2016
            InstanceName : MSSQLSERVER
            SqlInstance : sql2016
            SqlVersion : 13.0.4001
            ConnectingAsUser : BASE\ctrlb
            ConnectSuccess : True
            AuthType : Windows Authentication
            AuthScheme : KERBEROS
            TcpPort : 1433
            IPAddress : 10.2.1.5
            NetBiosName : sql2016.base.local
            IsPingable : True
            PSRemotingAccessible : True
            DomainName : base.local
            LocalWindows : 10.0.15063.0
            LocalPowerShell : 5.1.15063.502
            LocalCLR : 4.0.30319.42000
            LocalSMOVersion : 13.0.0.0
            LocalDomainUser : True
            LocalRunAsAdmin : False
 
        .NOTES
            Tags: CIM, Test, Connection
            Author: Chrissy LeMaire
 
            Website: https://dbatools.io
            Copyright: (C) Chrissy LeMaire, clemaire@gmail.com
            License: MIT https://opensource.org/licenses/MIT
    #>

    [CmdletBinding()]
    param (
        [parameter(ValueFromPipeline)]
        [Alias("ServerInstance", "SqlServer")]
        [DbaInstance[]]$SqlInstance,
        [PSCredential]$Credential,
        [PSCredential]$SqlCredential,
        [Alias('Silent')]
        [switch]$EnableException
    )
    process {
        foreach ($instance in $SqlInstance) {
            # Get local environment
            Write-Message -Level Verbose -Message "Getting local environment information"
            $localInfo = [pscustomobject]@{
                Windows    = [environment]::OSVersion.Version.ToString()
                PowerShell = $PSVersionTable.PSversion.ToString()
                CLR        = $PSVersionTable.CLRVersion.ToString()
                SMO        = ((([AppDomain]::CurrentDomain.GetAssemblies() | Where-Object { $_.Fullname -like "Microsoft.SqlServer.SMO,*" }).FullName -Split ", ")[1]).TrimStart("Version=")
                DomainUser = $env:computername -ne $env:USERDOMAIN
                RunAsAdmin = ([Security.Principal.WindowsPrincipal][Security.Principal.WindowsIdentity]::GetCurrent()).IsInRole([Security.Principal.WindowsBuiltInRole] "Administrator")
            }

            try {
                <# gather following properties #>
                <#
                        InputName :
                        ComputerName :
                        IPAddress :
                        DNSHostName :
                        DNSDomain :
                        Domain :
                        DNSHostEntry :
                        FQDN :
                        FullComputerName :
                     #>

                $resolved = Resolve-DbaNetworkName -ComputerName $instance.ComputerName -Credential $Credential
            }
            catch {
                Stop-Function -Message "Unable to resolve server information" -Category ConnectionError -Target $instance -ErrorRecord $_ -Continue
            }

            # Test for WinRM #Test-WinRM neh
            Write-Message -Level Verbose -Message "Checking remote acccess"
            try {
                $null = Invoke-Command2 -ComputerName $instance.ComputerName -Credential $Credential -ScriptBlock { Get-ChildItem } -ErrorAction Stop
                $remoting = $true
            }
            catch {
                $remoting = $_
            }

            # Test Connection first using Test-Connection which requires ICMP access then failback to tcp if pings are blocked
            Write-Message -Level Verbose -Message "Testing ping to $($instance.ComputerName)"
            $pingable = Test-Connection -ComputerName $instance.ComputerName -Count 1 -Quiet

            # SQL Server connection
            if ($instance.InstanceName -ne "MSSQLSERVER") {
                $sqlport = "N/A"
            }
            else {
                Write-Message -Level Verbose -Message "Testing raw socket connection to default SQL port"
                $tcp = New-Object System.Net.Sockets.TcpClient
                try {
                    $tcp.Connect($baseaddress, 1433)
                    $tcp.Close()
                    $tcp.Dispose()
                    $sqlport = $true
                }
                catch {
                    $sqlport = $false
                }
            }

            try {
                $server = Connect-SqlInstance -SqlInstance $instance.FullSmoName -SqlCredential $SqlCredential
                $connectSuccess = $true
            }
            catch {
                $connectSuccess = $false
                Stop-Function -Message "Issue connection to SQL Server on $instance" -Category ConnectionError -Target $instance -ErrorRecord $_ -Continue
            }

            $username = $server.ConnectionContext.TrueLogin
            if ($username -like "*\*") {
                $authType = "Windows Authentication"
            }
            else {
                $authType = "SQL Authentication"
            }

            # TCP Port
            try {
                $tcpport = (Get-DbaTcpPort -SqlInstance $server -EnableException).Port
            }
            catch {
                $tcpport = $_
            }

            # Auth Scheme
            try {
                $authscheme = (Test-DbaConnectionAuthScheme -SqlInstance $server -WarningVariable authwarning -WarningAction SilentlyContinue).AuthScheme
            }
            catch {
                $authscheme = $_
            }

            if ($authwarning) {
                $authscheme = "N/A"
            }

            [pscustomobject]@{
                ComputerName         = $resolved.ComputerName
                InstanceName         = $instance.InstanceName
                SqlInstance          = $instance.FullSmoName
                SqlVersion           = $server.Version
                ConnectingAsUser     = $username
                ConnectSuccess       = $connectSuccess
                AuthType             = $authType
                AuthScheme           = $authscheme
                TcpPort              = $tcpport
                IPAddress            = $resolved.IPAddress
                NetBiosName          = $resolved.FullComputerName
                IsPingable           = $pingable
                PSRemotingAccessible = $remoting
                DomainName           = $resolved.Domain
                LocalWindows         = $localInfo.Windows
                LocalPowerShell      = $localInfo.PowerShell
                LocalCLR             = $localInfo.CLR
                LocalSMOVersion      = $localInfo.SMO
                LocalDomainUser      = $localInfo.DomainUser
                LocalRunAsAdmin      = $localInfo.RunAsAdmin
            }
        }
    }
    end {
        Test-DbaDeprecation -DeprecatedOn "1.0.0" -EnableException:$false -Alias Test-SqlConnection
    }
}