# Apache Miscellaneous Documentation

Below is a list of additional documentation pages that apply to the Apache web server development project.

How to use XSSI and Negotiation for custom ErrorDocuments
  Describes a solution which uses XSSI and negotiation to custom-tailor the Apache ErrorDocuments to taste, adding the advantage of returning internationalized versions of the error messages depending on the client's language preferences.
File Descriptor use in Apache
  Describes how Apache uses file descriptors and talks about various limits imposed on the number of descriptors available by various operating systems.
`FIN_WAIT_2`
  A description of the causes of Apache processes going into the `FIN_WAIT_2` state, and what you can do about it.
Known Client Problems
  A list of problems in HTTP clients which can be mitigated by Apache.
Performance Notes -- Apache Tuning
  Notes about how to (run-time and compile-time) configure Apache for highest performance. Notes explaining why Apache does some things, and why it doesn't do other things (which make it slower/faster).
Security Tips
  Some "do"s - and "don't"s - for keeping your Apache web site secure.