The SERVERVARIABLE tag lets you display the value of a variable associated with the user's current web request.
There are a large number of server variables accessible to this tag as standard. Refer to the MSDN article titled IIS Server Variables for a list of standard variable names.
This element tag has the following default syntax:
<%# SERVERVARIABLE(Key) %>
Omitting the Key argument will cause the tag to render a full list of available server variables, including the name and value of each.
An example of a complete SERVERVARIABLE tag is as follows:
<%# SERVERVARIABLE(CERT_KEYSIZE) %>
When this tag is rendered, it will display the value assigned to the CERT_KEYSIZE variable.