Question

我们使用PowerShell脚本，有人将其从Microsoft下载新的Windows Defender病毒定义到网络位置。有四个文件可供下载。问题是，有时一个或多个下载因网络或网站问题而失败。所以，我希望任何下载都无法自动重试，直到成功。下面是脚本的相关部分。任何帮助将不胜感激。

# Source Addresses - Defender for Windows 10, 8.1 ################################

$sourceAVx86 = "http://go.microsoft.com/fwlink/?LinkID=121721&arch=x86"
$sourceNISx86 = "http://go.microsoft.com/fwlink/?LinkID=187316&arch=x86&nri=true"
$sourceAVx64 = "http://go.microsoft.com/fwlink/?LinkID=121721&arch=x64"
$sourceNISx64 = "http://go.microsoft.com/fwlink/?LinkID=187316&arch=x64&nri=true"

# Web client #####################################################################

$wc = New-Object System.Net.WebClient
$wc.Proxy = [System.Net.WebRequest]::DefaultWebProxy
$wc.Proxy.Credentials = [System.Net.CredentialCache]::DefaultNetworkCredentials

# x86 AV #########################################################################

$Dest = "$Destination\x86\" + 'mpam-fe.exe'
$wc.DownloadFile($sourceAVx86, $Dest) 

# x86 NIS ########################################################################

$Dest = "$Destination\x86\" + 'nis_full.exe'
$wc.DownloadFile($sourceNISx86, $Dest)

# x64 AV #########################################################################

$Dest = "$Destination\x64\" + 'mpam-fe.exe'
$wc.DownloadFile($sourceAVx64, $Dest)

# x64 NIS ########################################################################

$Dest = "$Destination\x64\" + 'nis_full.exe'
$wc.DownloadFile($sourceNISx64, $Dest)

Answer 1

一种方法是测试目的地是否存在文件。如果该文件不存在，则重试下载。我输入一个变量来设置在继续之前尝试下载的次数。

$maxAttempts = 5 #set the maximum number of attempts in case the download will never succeed.

$sourceAVx86 = "http://go.microsoft.com/fwlink/?LinkID=121721&arch=x86"
$sourceNISx86 = "http://go.microsoft.com/fwlink/?LinkID=187316&arch=x86&nri=true"
$sourceAVx64 = "http://go.microsoft.com/fwlink/?LinkID=121721&arch=x64"
$sourceNISx64 = "http://go.microsoft.com/fwlink/?LinkID=187316&arch=x64&nri=true"

$wc = New-Object System.Net.WebClient
$wc.Proxy = [System.Net.WebRequest]::DefaultWebProxy
$wc.Proxy.Credentials = [System.Net.CredentialCache]::DefaultNetworkCredentials

#Define destination file paths:
$DestAVx86 = "$Destination\x86\" + 'mpam-fe.exe'
$DestNISx86 = "$Destination\x86\" + 'nis_full.exe'
$DestAVx64 = "$Destination\x64\" + 'mpam-fe.exe'
$DestNISx64 = "$Destination\x64\" + 'nis_full.exe'

#Delete old versions of the files if they exist
if (Test-Path $DestAVx86) {
    Remove-Item $DestAVx86
}
if (Test-Path $DestNISx86) {
    Remove-Item $DestNISx86
}
if (Test-Path $DestAVx64) {
    Remove-Item $DestAVx64
}
if (Test-Path $DestNISx64) {
    Remove-Item $DestNISx64
}

$attemptCount = 0
Do {
    $attemptCount++
    $wc.DownloadFile($sourceAVx86, $Dest)
} while (((Test-Path $DestAVx86) -eq $false) -and ($attemptCount -le $maxAttempts))

$attemptCount = 0
Do {
    $attemptCount++
    $wc.DownloadFile($sourceNISx86, $Dest) 
} while (((Test-Path $DestNISx86) -eq $false) -and ($attemptCount -le $maxAttempts))

$attemptCount = 0
Do {
    $attemptCount++
    $wc.DownloadFile($sourceAVx64, $Dest) 
} while (((Test-Path $DestAVx64) -eq $false) -and ($attemptCount -le $maxAttempts))

$attemptCount = 0
Do {
    $attemptCount++
    $wc.DownloadFile($sourceNISx64, $Dest) 
} while (((Test-Path $DestNISx64) -eq $false) -and ($attemptCount -le $maxAttempts))

如果下载失败，请重试PowerShell命令

1 个答案: