[Azure]ARM模式下删除虚拟机挂盘修复后恢复的脚本（托管磁盘）

使用Azure虚拟机经常会遇到无法连接的问题，比如我们修改了虚拟机防火墙，修改了注册表，修改了配置文件，系统磁盘文件系统挂掉了等等。

遇到这种问题的时候，由于Azure没有开放控制台登录虚拟机的功能，所以只能将原来的虚拟机以保留磁盘的方式删除掉，然后将系统磁盘挂载到其他机器上修复各种问题，再使用修复后的磁盘重新创建出虚拟机来。

对于经典虚拟机（ASM）来说，挂盘后的重建可以通过界面完成，但是ARM虚拟机目前使用vhd创建的话，只能通过Azure Powershell进行，而且很多虚拟机的创建参数都需要提前记录下来，包括数据磁盘，网卡等都要在重建的过程中依次配好，对于没有使用过Azure Powershell的用户来说，可能难度比较大一些。

下面这个脚本提供了一个非常方便的功能，脚本首先会收集指定虚拟机的信息并输出到屏幕，然后我们输入continue后，脚本会将这台虚拟机删除掉，删除掉之后，脚本会等待用户输入，这个时候，就可以将保留下来的磁盘挂载到其他机器上修复了，修复完成后，将磁盘分离下来，然后按Enter键继续执行脚本，脚本会再利用原来的磁盘将虚拟机还原回来。

这个脚本针对的是托管磁盘的虚拟机。

脚本如下：

param(
[Parameter(Mandatory = $true)]
[string]$SubscriptionName,

[Parameter(Mandatory = $true)]
[string]$ResourceGroupName,

[Parameter(Mandatory = $true)]
[string]$VMName
)

Function GetResourceNameFromResourceId($resourceId)
{
return $resourceId.Substring($resourceId.LastIndexOf('/') + 1);
}

Function GetResourcePropertyFromResourceId($resourceId, $propertyName)
{
$propertyName = $propertyName + "/";
$rgName = $resourceId.Substring($resourceId.IndexOf($propertyName) + $propertyName.Length);
return $rgName.Substring(0, $rgName.IndexOf("/"));
}

Function CollectVMInformation($rgName, $vmName)
{
$vmInfo = @{};
$vmInfo.Add("ResourceGroup", $rgName);
$vmInfo.Add("Name", $vmName);

$vm = Get-AzureRmVM -ResourceGroupName $rgName -Name $vmName -ErrorAction Ignore -WarningAction Ignore;
if ($vm -eq $null)
{
return $null;
}

$vmInfo.Add("Size", $vm.HardwareProfile.VmSize);
$vmInfo.Add("Location", $vm.Location);
if ($vm.AvailabilitySetReference -ne $null)
{
$vmInfo.Add("AvailabilitySet", $vm.AvailabilitySetReference.Id);
}

$vmInfo.Add("OSType", $vm.StorageProfile.OsDisk.OsType.ToString());

#network properties
$nicId = ($vm.NetworkProfile.NetworkInterfaces | where {$_.Primary -eq $true}).Id;
if ($nicId -eq $null -and $vm.NetworkProfile.NetworkInterfaces.Count -eq 1)
{
$nicId = $vm.NetworkProfile.NetworkInterfaces[0].Id;
}
$vmInfo.Add("PrimaryNetworkInterfaceId", $nicId);

$secondaryNics = @($vm.NetworkProfile.NetworkInterfaces | where {$_.Primary -eq $false});
$vmInfo.Add("SecondaryNetworkInterfaces", $secondaryNics);

#disk
$vmInfo.Add("OSDisk", $vm.StorageProfile.OsDisk);
$vmInfo.Add("DataDisks", @($vm.StorageProfile.DataDisks));

Write-Host ("{0, -16}: {1}" -f "Name", $vmInfo["Name"]) -ForegroundColor Cyan;
Write-Host ("{0, -16}: {1}" -f "Resource Group", $vmInfo["ResourceGroup"]) -ForegroundColor Cyan;
Write-Host ("{0, -16}: {1}" -f "Size", $vmInfo["Size"]) -ForegroundColor Cyan;
Write-Host ("{0, -16}: {1}" -f "Location", $vmInfo["Location"]) -ForegroundColor Cyan;
Write-Host ("{0, -16}: {1}" -f "OS Type", $vmInfo["OSType"]) -ForegroundColor Cyan;
if ($vmInfo.ContainsKey("AvailabilitySet"))
{
Write-Host ("{0, -16}: {1}" -f "Availability Set", $vmInfo["AvailabilitySet"]) -ForegroundColor Cyan;
}
Write-Host ("{0, -16}: {1}" -f "Primary NIC", $vmInfo["PrimaryNetworkInterfaceId"]) -ForegroundColor Cyan;
foreach ($secondaryNic in $vmInfo["SecondaryNetworkInterfaces"])
{
Write-Host ("{0, -16}: {1}" -f "Secondary NIC", $secondaryNic.Id) -ForegroundColor Cyan;
}
Write-Host ("{0, -16}: {1}" -f "OS Disk", $vmInfo["OSDisk"].Name) -ForegroundColor Cyan;
foreach ($dataDisk in $vmInfo["DataDisks"])
{
Write-Host ("{0, -16}: {1}" -f "Data Disk", $dataDisk.Name) -ForegroundColor Cyan;
}

return $vmInfo;
}

Function DeleteOldVM($rgName, $vmName)
{
[void](Remove-AzureRmVM -ResourceGroupName $rgName -Name $vmName -Force);
#if lease is not broken, we need to sleep for some time
#sleep 10
}

Function RebuildVM($vmInfo)
{
#basic information
$rgName = $vmInfo["ResourceGroup"];
$vmName = $vmInfo["Name"];
$vmSize = $vmInfo["Size"];
$location = $vmInfo["Location"];
$osType = $vmInfo["OSType"];

#network
$primaryNicId = $vmInfo["PrimaryNetworkInterfaceId"];
$secondaryNics = $vmInfo["SecondaryNetworkInterfaces"];

#disk
$osDisk = $vmInfo["OSDisk"];
$dataDisks = $vmInfo["DataDisks"];

$vmconfig = $null;
if ($vmInfo.ContainsKey("AvailabilitySet"))
{
$avaSetId = $vmInfo["AvailabilitySet"];
$vmconfig = New-AzureRmVMConfig -VMName $vmName -VMSize $vmSize -AvailabilitySetId $avaSetId;
}
else
{
$vmconfig = New-AzureRmVMConfig -VMName $vmName -VMSize $vmSize;
}
$vmconfig = $vmconfig | Set-AzureRmVMBootDiagnostics -Disable;

if ($osType -eq "Windows")
{
$vmconfig = $vmconfig | Set-AzureRmVMOSDisk -ManagedDiskId $osDisk.ManagedDisk.Id -Caching $osDisk.Caching -CreateOption attach -Windows;
} else {
$vmconfig = $vmconfig | Set-AzureRmVMOSDisk -ManagedDiskId $osDisk.ManagedDisk.Id -Caching $osDisk.Caching -CreateOption attach -Linux;
}
#下面这个步骤是必须要有而且非常重要的，实测下来发现上面的命令有个小bug，就是托管磁盘添加后，磁盘名默认会被设置成虚拟机名称
#导致创建的时候报错“New-AzureRmVM : Changing property 'osDisk.name' is not allowed”
$vmconfig.StorageProfile.OsDisk.Name = $osDisk.Name;
$vmconfig.StorageProfile.ImageReference = $null;

$index = 0;
foreach ($dataDisk in $dataDisks)
{
$vmconfig = $vmconfig | Add-AzureRmVMDataDisk -ManagedDiskId $dataDisk.ManagedDisk.Id -Lun $dataDisk.Lun -Caching $dataDisk.Caching -CreateOption attach;
#下面这个步骤是必须要有而且非常重要的，实测下来发现上面的命令有个小bug，就是托管磁盘添加后，磁盘名默认会被设置成虚拟机名称
#导致创建的时候报错“New-AzureRmVM : Changing property 'dataDisk.name' is not allowed”
$vmconfig.StorageProfile.DataDisks[$index].Name = $dataDisk.Name;
$index += 1;
}

$vmconfig = $vmconfig | Add-AzureRmVMNetworkInterface -Id $primaryNicId -Primary;
foreach ($secondaryNic in $secondaryNics)
{
$secondaryNicId = $secondaryNic.Id;
$vmconfig = $vmconfig | Add-AzureRmVMNetworkInterface -Id $secondaryNicId;
}

[void](New-AzureRmVM -ResourceGroupName $rgName -Location $location -VM $vmconfig);
}

[void](Select-AzureRmSubscription -SubscriptionName $SubscriptionName);

Write-Host "Virtual Machine information before deletion:" -ForegroundColor Green;
$vmInfo = (CollectVMInformation $ResourceGroupName $VMName);
if ($vmInfo -eq $null)
{
Write-Host "Failed to collect vm information." -ForegroundColor Red;
return;
}

If ((Read-Host "Enter 'continue' to delete VM") -ne "continue")
{
Write-Host "Canceled" -ForegroundColor Yellow;
return;
}

Write-Host "Deleting old VM..." -ForegroundColor Yellow;
DeleteOldVM $ResourceGroupName $VMName;

Write-Host "VM deleted" -ForegroundColor Yellow;
Read-Host "Press enter to rebuild VM";

Write-Host "Rebuilding VM..." -ForegroundColor Yellow;
RebuildVM $vmInfo;
Write-Host "Virtual Machine information after rebuild:" -ForegroundColor Green;
[void](CollectVMInformation $ResourceGroupName $VMName);

Write-Host "Finished" -ForegroundColor Yellow;
执行结果：