通过上一篇的简介，相信各位对于简单的创建alert，以及Azure monitor使用以及大概有个印象了。基础的使用总是非常简单的，这里再分享一个常用的alert使用方法

实际工作中，不管是日常运维还是做项目，我们都需要知道VM的实际性能情况，避免出现性能瓶颈，因此创建alert是一种非常方便的方式，我们可以通过alert第一时间知道系统出现了性能的瓶颈，以便尽快采取解决措施。

因此，也衍生了一个实际的问题，单独为一台VM开启alert很简单，但是如果我们需要为一个资源组内十几甚至几十上百台VM统一创建alert，则会非常麻烦

在这里分享一个自己写的简单脚本，可以通过批量的方式为一个资源组内的所有VM，或者是某个单独的VM创建alert，省去很多不必要的重复性工作，以下是代码的内容

<# .NOTES===========================================================================Created with:  SAPIEN Technologies, Inc., PowerShell Studio 2017 v5.4.134Created on:    2019/1/10 13:19Created by:    mxyOrganization:  Filename:      ===========================================================================.DESCRIPTIONA description of the file.
#>
param
([parameter(Mandatory = $true)][string]$RGName,#资源组名称[parameter(Mandatory = $false)][string]$VmName,#VM名称[parameter(Mandatory = $true)][string]$MailAddress,#邮件地址[parameter(Mandatory = $false)][ValidateSet("CPU", "Memory")][string]$Metric = "CPU",#需要针对哪个metric创建alert,方便起见这里目前只是设置了CPU和内存两种[parameter(Mandatory = $false)][ValidateSet("GreaterThan", "GreaterThanOrEqual", "LessThan", "LessThanOrEqual")][string]$Operation = "GreaterThan",#操作条件[parameter(Mandatory = $false)][int]$Threshold = 50,#阈值[parameter(Mandatory = $false)][ValidateSet("Average", "Last", "Maximum", "Minimum", "Total")]#计算方式，是平均还是最大等[string]$TimeAggregationOperator = "Average",[parameter(Mandatory = $false)][TimeSpan]$WindowSize = "00:05:00"#时间戳)function Write-DateTimeMessage
{param ([parameter(Mandatory = $false)][switch]$Warning,[parameter(Mandatory = $true)][string]$Message,[parameter(Mandatory = $false)][string]$ForegroundColor)if ($Warning){Write-Warning ($(Get-Date -UFormat '%Y/%m/%d %H:%M:%S') + " * " + $Message)}else{if ($ForegroundColor){Write-Host ($(Get-Date -UFormat '%Y/%m/%d %H:%M:%S') + " * " + $Message) -ForegroundColor $ForegroundColor}else{Write-Host ($(Get-Date -UFormat '%Y/%m/%d %H:%M:%S') + " * " + $Message)}}}#Get metric name
switch ($Metric)
{Memory {$MetricName = "\Memory\% Committed Bytes In Use"}CPU {$MetricName = "\Processor Information(_Total)\% Processor Time"}default{#<code>}
}
#Find the vm if vmname parameter specified
try
{$Error.Clear()if ($VmName){Write-DateTimeMessage "Trying to find vm $VmName in resource group $RGName"$vms = Get-AzureRmVM -ResourceGroupName $RGName -Name $VmName -ErrorAction StopWrite-DateTimeMessage "vm $VmName Found in resource group $RGName"}else{$vms = Get-AzureRmVM -ResourceGroupName $RGName -ErrorAction Stop}# Create action email$actionEmail = New-AzureRmAlertRuleEmail -CustomEmail $MailAddress -WarningAction SilentlyContinue# Get resource id and add alertif ($vms -ne $null){foreach ($vm in $vms){$vmID = $vm.id$AlertName = $vm.Name + "_Alert_" + $Metric + "_" + $Operation + "_" + $Threshold + "_" + $actionEmail.CustomEmails$Error.Clear()Write-DateTimeMessage "Trying to add alert for vm $($vm.Name) ..."Add-AzureRmMetricAlertRule -Name $AlertName -Location "ChinaEast" -ResourceGroup $RGName -TargetResourceId $vmID -MetricName $MetricName -Operator $Operation -Threshold $Threshold -WindowSize $WindowSize -TimeAggregationOperator $TimeAggregationOperator -Action $actionEmail -ErrorAction 'Stop' -WarningAction 'SilentlyContinue' | Out-NullWrite-DateTimeMessage "Add alert for vm $($vm.Name) successfully!"}}else{Write-DateTimeMessage "No vm in resource group $RGName"}}
catch
{Write-DateTimeMessage $Error[0].Exception.Message
}

可以看到脚本很简单，运行方法这里举个例子，比如要为mxytest这个资源组下的所有VM创建CPU10分钟之内大于80便发邮件给abc@abc.com的alert，则可以按照以下方式运行

.\Create-AzureAlert.ps1 -RGName mxytest -MailAddress "abc@abc.com" -Metric CPU -Operation GreaterThan -Threshold 80 -TimeAggregationOperator Average -WindowSize "00:10:00"

创建完成后即可在alert中国看到对应的内容

Get-AzureRmAlertRule -ResourceGroupName mxytest -WarningAction SilentlyContinue

也可以通过PowerShell获取到信息