删除老的Azure Blob Snapshot

客户有这样的需求：每天需要对VM的数据进行备份，但如果备份的时间超过一定的天数，需要进行清除。

本文也是在前一篇Azure Blob Snapshot上的优化。

"Azure blob Storage Snapshot"里，删除Snapshot的思路是遍历所有Storage Account，找到所有的vhd文件，看看是否有Snapshot，如果有判断是否超过14天，如果超过则删除，如果没有超过，则保留。

本文的思路是：

获取所有的虚拟机，判断虚拟机是否运行，如果运行，获取这台虚拟机上所有的硬盘。

如果硬盘的Snapshot超过我们给定的时间，删除，否则不做操作。

具体的脚本如下：

 function DeleteOlderSnapshot {
   [CmdletBinding()]
   param (
     [Parameter (Mandatory=$True,
                 ValueFromPipeLine=$True,
                 HelpMessage="BeforeTheDayWillBeDelete")]

     [String] $Day,
     [switch] $LogErrors
   )
   BEGIN{
     Write-Verbose "Error Log will Be $ErrorLog"
     }
   Process
   {

     $vms = Get-AzureVM
     $now = Get-Date
     foreach ($vm in $vms)
     {
         if($vm.Status -eq "ReadyRole")
         {
             $osblobname = ($vm.VM.OSVirtualHardDisk).MediaLink.ToString().Split("/")[-1]
             $osblobcontainer = ($vm.VM.OSVirtualHardDisk).MediaLink.ToString().Split("/")[-2]
             $osblobsa = ($vm.VM.OSVirtualHardDisk).MediaLink.ToString().Split("/")[-3].Split(".")[0]

             $storagekey = (Get-AzureStorageKey -StorageAccountName $osblobsa).Primary
             $ctr = New-AzureStorageContext -StorageAccountName $osblobsa -StorageAccountKey $storagekey -Environment AzureChinaCloud

             $blobs = Get-AzureStorageBlob -Container $osblobcontainer -Context $ctr | Where-Object {$_.Name -match $osblobname}

             foreach ($blob in $blobs)
             {
                 if($blob.ICloudBlob.IsSnapshot)
                 {

                     $diff = [datetime]::FromBinary($now.Ticks-$blob.SnapshotTime.Ticks)
                     write-host $blob.name  "is a snapshot"  "snapshot time is"  $diff.DayOfYear "days"
                     if ( $diff.dayofyear -ge $Day)
                     {

                         write-host "delete"
                         $blob.ICloudBlob.Delete()
                     }

                 }else{
                     write-host $blob.Name  "is original disk"
                 }
             }

             $count = $vm.VM.DataVirtualHardDisks.Count

             for($i=0;$i -lt $count;$i++)
             {
                 $datablobname = ($vm.VM.DataVirtualHardDisks)[$i].MediaLink.ToString().Split("/")[-1]
                 $datablobcontainer = ($vm.VM.DataVirtualHardDisks)[$i].MediaLink.ToString().Split("/")[-2]
                 $datablobsa = ($vm.VM.DataVirtualHardDisks)[$i].MediaLink.ToString().Split("/")[-3].Split(".")[0]
                 $storagekey = (Get-AzureStorageKey -StorageAccountName $datablobsa).Primary
                 $ctr = New-AzureStorageContext -StorageAccountName $datablobsa -StorageAccountKey $storagekey -Environment AzureChinaCloud

                 $blobs = Get-AzureStorageBlob -Container $datablobcontainer -Context $ctr | Where-Object {$_.Name -match $datablobname}
                 foreach ($blob in $blobs)
                 {
                     if($blob.ICloudBlob.IsSnapshot)
                     {

                         $diff = [datetime]::FromBinary($now.Ticks-$blob.SnapshotTime.Ticks)
                         write-host $blob.name  "is a snapshot"  "snapshot time is"  $diff.DayOfYear "days"
                         if ( $diff.dayofyear -ge $Day)
                         {

                             write-host "delete"
                             $blob.ICloudBlob.Delete()
                         }

                     }else{
                         write-host $blob.Name  "is original disk"
                     }
                 }
             }
         }
     }

   }
   end {}
   }
   DeleteOlderSnapshot -Day 2