Peter Hinchley

Learning in Public

✪ Configure an IIS Rewrite Rule using PowerShell

In this short post I will demonstrate how you can rewrite requests to resources hosted on an IIS web server.

Firstly, you need to download and install the IIS rewrite module from Microsoft. To install the x64 version of the module, run:

msiexec.exe /i rewrite_amd64.msi /qb

The next step is to create a rewrite rule. As an example, the following PowerShell script will create a rule named XXXX that will rewrite any request for "foo.txt", from any client with an IP address in the range 100.0.0.1 - 100.0.0.254, to "bar.txt":

$name = 'XXXX'
$inbound = 'foo\.txt'
$outbound = 'bar.txt'
$range = '100\.0\.0\.\d+'
$site = 'IIS:\Sites\Default Web Site'
$root = 'system.webServer/rewrite/rules'
$filter = "{0}/rule[@name='{1}']" -f $root, $name

Add-WebConfigurationProperty -PSPath $site -filter $root -name '.' -value @{name=$name; patterSyntax='Regular Expressions'; stopProcessing='False'}
Set-WebConfigurationProperty -PSPath $site -filter "$filter/match" -name 'url' -value $inbound
Set-WebConfigurationProperty -PSPath $site -filter "$filter/conditions" -name '.' -value @{input='{REMOTE_ADDR}'; matchType='0'; pattern=$range; ignoreCase='True'; negate='False'}
Set-WebConfigurationProperty -PSPath $site -filter "$filter/action" -name 'type' -value 'Rewrite'
Set-WebConfigurationProperty -PSPath $site -filter "$filter/action" -name 'url' -value $outbound

This is what the resultant rule should look like in IIS:

Inbound Rewrite Rule