Redirect traffic from single site collection in Sharepoint on-prem via URL rewrite IIS module

Suppose that you have Sharepoint on-prem web application with multiple site collections which have own urls and need to perform maintenance work on one of these site collections so others will remain working. In order to do that you may temporary redirect traffic from this site collection to external page (e.g. to maintenance page hosted outside of this site collection). Technically it can be done by adding URL rewrite rule to Sharepoint web app in IIS. Rule will look like this:

This rule will redirect traffic from site collection with url /test to external site http://example.com. This is the same rule in xml which is added to web.config of Sharepoint web app:

<rewrite>
  <rules>
	<rule name="MyRule" enabled="true" stopProcessing="true">
	  <match url="test/*" />
	  <action type="Redirect" url="http://example.com" appendQueryString="false" redirectType="Found" />
	</rule>
  </rules>
</rewrite>

Note that if you perform temporary maintenance work on site collection then Redirect type should be set to Found (302) like shown above and not to Permanent (301). In case of permanent redirect browser will cache response and will redirect users from this site collection even after maintenance will be completed and rule will be removed from the site.