DHCP Lease Report.ps1

$DayDate=(get-date (get-date).AddDays(-1) -Format dddd)
$FileDate=(get-date (get-date).AddDays(-1) -format "MM-dd-yyyy")
$SubjectDate=(get-date (Get-Date).AddDays(-1) -format 'dddd MMMM dd, yyyy')

$DHCPLogLocation='C:\windows\system32\dhcp'
$Day=$DayDate[0..2] -join ''
$LogName="DhcpSrvLog-$Day"
$LogFile="$LogName.log"
$LogFullPath="$DHCPLogLocation\$LogFile"

$LogAssignsFile="DhcpSrvLog-$FileDate-Assigns.csv"
$LogRenewsFile="DhcpSrvLog-$FileDate-Renews.csv"

$TempLocation="C:\temp"

if(!(Test-Path $TempLocation))
{
    New-Item -Path $TempLocation -ItemType Directory | Out-Null
}

$LogFileContent=Get-Content $LogFullPath

$IPLeases=$LogFileContent | select -Skip 34 | where {$($_).substring(0,2) -match '^10$|^11$'}

$AllLeases=@()
foreach($Lease in $IPLeases)
{
    
    $LeaseSplit=$Lease -split ','
    
    $LeaseArray=New-Object -TypeName psobject
    
    $LeaseArray | Add-Member –MemberType NoteProperty –Name 'DateTime' -Value $(get-date "$($LeaseSplit[1]) $($LeaseSplit[2])")
    $LeaseArray | Add-Member –MemberType NoteProperty –Name 'Description' -Value $LeaseSplit[3]
    $LeaseArray | Add-Member –MemberType NoteProperty –Name 'IP Address' -Value $LeaseSplit[4]
    $LeaseArray | Add-Member –MemberType NoteProperty –Name 'Host Name' -Value $LeaseSplit[5]
    $LeaseArray | Add-Member –MemberType NoteProperty –Name 'MAC Address' -Value $LeaseSplit[6]

    $AllLeases+=$LeaseArray

}

$Renews=$AllLeases | where {$_.Description -eq "Renew"} | select DateTime,'IP Address','Host Name','MAC Address' |  export-csv -NoTypeInformation "$TempLocation\$LogAssignsFile"
$Assigns=$AllLeases | where {$_.Description -eq "Assign"} | select DateTime,'IP Address','Host Name','MAC Address' | export-csv -NoTypeInformation "$TempLocation\$LogRenewsFile"


$Username="DomainUsername@domain.local" # Replace with actual email username 
$Password="PlainTextPassword" | ConvertTo-SecureString -Force -AsPlainText # See http://www.adminarsenal.com/admin-arsenal-blog/secure-password-with-powershell-encrypting-credentials-part-1/ for more ways to pull password, please do not actually store in the powershell script
$Creds=New-Object -TypeName System.Management.Automation.PSCredential -ArgumentList $Username, $Password

$Attachments=@("$TempLocation\$LogAssignsFile","$TempLocation\$LogRenewsFile")

$Subject="DHCP Logs for $SubjectDate"
$Body="<h1>DHCP Logs Attached:</h1><ul><li>$LogAssignsFile</li><li>$LogRenewsFile</li></ul>"
$To="<recipient email address>" # Replace wtih actual TO Address
$From="<sender email address>" # Replace with actual FROM Address
$SMTPServer="<SMTP Server>" # Replace with actual SMTP Server

Send-MailMessage -Attachments $Attachments -Body $Body -To $To -From $From -Subject $Subject -SmtpServer $SMTPServer -BodyAsHtml -Credential $Creds

foreach($File in $Attachments)
{
    Remove-Item $File
}