Best practice for maintaining lists of redirect urls with IIS 8?

Question

Some website changes caused redirect lists with 400+ URLs. What is the best way to maintain these? Adding them one by one is not a good option. Adding them to the the web-config causes the file to grow to the point of the system being unable to read it.

Is there a way to maintain a separate file with redirects in IIS 8?

Answer 1

From my experience best way is to use rewrite maps:

Create rewriteMaps.config

<rewriteMaps>
    <rewriteMap name="Redirects">
        <add key="/test.aspx" value="/test2.aspx" />
        <add key="/aboutus.aspx" value="/about" />
    </rewriteMap>
</rewriteMaps>

Create rewriteRules.config

<rules>
    <rule name="Rule for Redirects">
        <match url=".*" />
        <conditions>
        <add input="{Redirects:{REQUEST_URI}}" pattern="(.+)" />
        </conditions>
        <action type="Redirect" url="{C:1}" appendQueryString="false" />
    </rule>  
</rules>

In web.config use configSource attribute

<rewrite>
    <rewriteMaps configSource="rewriteMaps.config" />
    <rules configSource="rewriteRules.config" />
</rewrite>

Benefits of this structure

• Web.config small and clean
• You can put complex redirects/rewrites with conditions in rewriteRules.config
• You can put simple redirects (redirect pathA to pathB) directly into rewriteMaps.config as key-value pair