internal/Test-SqlSa.ps1

Function Test-SqlSa
{
<#
.SYNOPSIS
Internal function. Ensures sysadmin account access on SQL Server.
#>

    [CmdletBinding()]
    param (
        [Parameter(Mandatory = $true)]
        [ValidateNotNullOrEmpty()]
        [Alias("ServerInstance", "SqlServer")]
        [object]$SqlInstance,
        [PSCredential]$SqlCredential
    )
    
    try
    {
        
        if ($SqlInstance.GetType() -eq [Microsoft.SqlServer.Management.Smo.Server])
        {
            return ($SqlInstance.ConnectionContext.FixedServerRoles -match "SysAdmin")
        }
        
        $server = Connect-SqlInstance -SqlInstance $SqlInstance -SqlCredential $SqlCredential
        return ($server.ConnectionContext.FixedServerRoles -match "SysAdmin")
    }
    catch { return $false }
}