Powershell script for backup Xenserver and XCP-ng VMs while running (tested with Xenserver 7.0 and XCP-ng 7.5 VMs)

XenBackup.ps1

# This script reads virtual machines to backup from an xml
# configuration file by default named XenBackup.xml.
# The configuration file can be given as parameter -config, for example
#
#   XenBackup.ps1 -config "XenBackup-test.xml"
#
# [If not given is used the file XenBackup.xml]
#
# The values of maxBackups and backupDir
# can be overridden on specific machine.
# This is an example:
# 
# <?xml version="1.0"?>
# <XenBackup>
#     <backupDir>C:\BACKUPS</backupDir>
#     <maxBackups>2</maxBackups>
#     <logFile>XenBackup.log</logFile>
#     <server host="xenserver001" user="root" password="password">
#        <vm name="TEST2"/>
#        <!-- override maxBackups and backupDir -->
#        <vm name="Test VM" maxBackups="2" backupDir="C:\BACKUPS2"/>
#        <vm name="Ubuntu Xenial" />
#        <vm name="Knoppix" />
#     </server>
#     <server host="xenserver002" user="root" password="password">
#        <vm name="Knoppix2" />
#     </server>
# </XenBackup>
param (
   [string]$config = "XenBackup.xml"
)

$configFile = $config

Write-Host("READING CONFIGURATION FROM FILE: " + $configFile)
[xml]$config = Get-Content $configFile

Import-Module XenServerPSModule

function go() {
    Write-Log("CONFIGURATION LOADED FROM: " + $configFile)
    foreach( $server in $config.XenBackup.server ) {
        Connect-XenServer -NoWarnCertificates -NoWarnNewCertificates -url ("https://" + $server.host) $server.user $server.password
        Write-Log("CONNECTED TO SERVER: " + $server.host)
    
        foreach($vm in $server.vm) {
            Write-Log("BACKUPING VM: " + $vm.name)
            backupVm $server $vm
            cleanOldBackups $vm
        }

        Disconnect-XenServer
        Write-Log("DISCONNECTED FROM SERVER: " + $server.host)
    }
}

function backupVm($server, $vm) {
    $bckdir = $config.XenBackup.backupDir
    if ($vm.backupDir) { $bckdir = $vm.backupDir }

    $timestamp = (Get-Date -Format "yyyy-MM-ddTHHmmss")
    $snapshot_name = $vm.name + "_bck_$timestamp"

    #Create temporary snapshot for hot backup
    Invoke-XenVM -Name $vm.name -XenAction Snapshot -NewName $snapshot_name
    $snapshot = Get-XenVM -Name $snapshot_name

    #Set is-a-template and ha-always-run to false
    Set-XenVM -Uuid $snapshot.uuid -IsATemplate $false -HaAlwaysRun $false

    #Export snapshot
    setTempDir $bckdir
    Export-XenVM -Uuid $snapshot.uuid -XenHost $server.host -Path ($bckdir + "\" + $vm.name + "-${timestamp}.xva")
    
    #Get disk snapshots (for removal)
    $vdis = @()
    foreach($vbd in $snapshot.VBDs) {
        if((Get-XenVBDProperty -Ref $vbd -XenProperty Mode) -eq [XenAPI.vbd_mode]::RW) {
            $vdis += Get-XenVBDProperty -Ref $vbd -XenProperty VDI
        }
    }
  
    #Remove vm snapshot (this does not remove disk snapshots)
    Remove-XenVM -Uuid $snapshot.uuid

    #Remove disks snapshots
    foreach($vdi in $vdis) {
        Remove-XenVDI -VDI $vdi
    }
}

function setTempDir($newdir) {
    $env:TMP  = $newdir
    $env:TEMP = $newdir
}

function cleanOldBackups($vm) {
    $maxbkps = $config.XenBackup.maxBackups
    $bckdir = $config.XenBackup.backupDir
    if ($vm.maxBackups) { $maxbkps = $vm.maxBackups }
    if ($vm.backupDir) { $bckdir = $vm.backupDir }

    Write-Log("MAXBACKUPS: " + $maxbkps)

    $vmbackupfiles = Get-ChildItem -Path $bckdir -File -Filter ($vm.name + "-*.xva") | sort name -Descending
    
    $count = 0
    foreach( $f in $vmbackupfiles ) {
        $count++

        Write-Log($count) 
        if ($count -gt $maxbkps) {
            Write-Log("DELETING " + $f)
            Remove-Item -Path ($bckdir + "\" + $f)
        } else {
            Write-Log("LEAVING " + $f)
        }

    }

}

Function Write-Log {
   Param ([string]$message)
   $logfile = $config.XenBackup.logFile
   $stamp = (Get-Date).toString("yyyy/MM/dd HH:mm:ss")
   $line = "$stamp - $message"

   Add-content $logfile -Value $line
}

go

XenBackup.xml

<?xml version="1.0"?>
<XenBackup>
    <backupDir>C:\BACKUPS</backupDir>
    <maxBackups>2</maxBackups>
    <logFile>XenBackup.log</logFile>
    <server host="xenserver001" user="root" password="password">
       <vm name="TEST2"/>
       <!-- override maxBackups and backupDir -->
       <vm name="Test VM" maxBackups="2" backupDir="C:\BACKUPS2"/>
    </server>
    <server host="xenserver002" user="root" password="password">
       <vm name="Filemaker" maxBackups="3"/>
    </server>
    <server host="xenserver003" user="root" password="password">
       <vm name="Ubuntu Xenial" />
       <vm name="Knoppix" />
    </server>
</XenBackup>

XenBackup.xml-scheduled-task.xml

<?xml version="1.0" encoding="UTF-16"?>
<Task version="1.2" xmlns="http://schemas.microsoft.com/windows/2004/02/mit/task">
  <RegistrationInfo>
    <Date>2016-10-26T09:15:12.7978673</Date>
    <Author>Administrator</Author>
  </RegistrationInfo>
  <Triggers />
  <Principals>
    <Principal id="Author">
      <UserId>S-1-5-18</UserId>
      <RunLevel>HighestAvailable</RunLevel>
    </Principal>
  </Principals>
  <Settings>
    <MultipleInstancesPolicy>IgnoreNew</MultipleInstancesPolicy>
    <DisallowStartIfOnBatteries>true</DisallowStartIfOnBatteries>
    <StopIfGoingOnBatteries>true</StopIfGoingOnBatteries>
    <AllowHardTerminate>true</AllowHardTerminate>
    <StartWhenAvailable>false</StartWhenAvailable>
    <RunOnlyIfNetworkAvailable>false</RunOnlyIfNetworkAvailable>
    <IdleSettings>
      <StopOnIdleEnd>true</StopOnIdleEnd>
      <RestartOnIdle>false</RestartOnIdle>
    </IdleSettings>
    <AllowStartOnDemand>true</AllowStartOnDemand>
    <Enabled>true</Enabled>
    <Hidden>false</Hidden>
    <RunOnlyIfIdle>false</RunOnlyIfIdle>
    <WakeToRun>false</WakeToRun>
    <ExecutionTimeLimit>P3D</ExecutionTimeLimit>
    <Priority>7</Priority>
  </Settings>
  <Actions Context="Author">
    <Exec>
      <Command>powershell</Command>
      <Arguments>-file XenBackup.ps1 -config XenBackup.xml</Arguments>
      <WorkingDirectory>C:\XenBackup</WorkingDirectory>
    </Exec>
  </Actions>
</Task>