# Apache server Frequently Asked Questions

## The Questions

1. What is Apache ?
2. Why was Apache created ?
3. How does the Apache group relate to the NCSA 1.4+ effort ?
4. Why the name "Apache" ?
5. How compatible is Apache with my existing NCSA 1.3 setup ?
6. Why didn't the Apache group wait for NCSA 1.4 ?
7. OK, so how does Apache compare to other servers ?
8. How thoroughly tested is Apache?
9. What extensions does Apache offer over NCSA 1.x?
10. Does or will Apache act as a Proxy server?
11. What NCSA 1.3 bugs are fixed in Apache ?
12. What are the future plans for Apache ?
13. Who do I contact for support ?
14. Is there any more information on Apache ?
15. Where can get Apache ?

## The Answers

1. What is Apache ?

   Apache was originally based on code and ideas found in the most popular HTTP server of the time.. NCSA httpd 1.3 (early 1995). It has since evolved into a far superior system which can rival (and probably surpass) almost any other UNIX based HTTP server in terms of functionality, efficiency and speed. It has several new features (among which are highly configurable error messages, DBM-based authentication databases, and content negotiation). It also offers dramatically improved performance, and fixes many bugs in the NCSA 1.3 code.

2. How does the Apache group relate to the NCSA 1.4 effort ?

   We are, of course, aware of NCSA's ongoing efforts towards the release of a 1.4 version of their server (as they are aware of ours; in fact, the current NCSA beta contains some code written by members of the Apache group). Once NCSA 1.4 has been released, we hope to incorporate most of its innovations (and perhaps to transition entirely to a 1.4 code base). However, these are independent efforts.

3. Why was Apache created ?

   to address concerns of a group of www providers and part time httpd programmers, that httpd didn't behave as they wanted it to.

4. Why the name "Apache" ?

   A cute name which stuck. Apache is "A PAtCHy server". It was based on some existing code and a series of "patch files".

5. How compatible is Apache with my existing NCSA 1.3 setup ?

   Apache attempts to offer all the features and configuration options of NCSA httpd 1.3, as well as many of the additional features found in NCSA httpd 1.4 and NCSA httpd 1.5.

   NCSA httpd appears to be moving toward adding experimental features which are not generally required at the moment. Some of the experiments will succeed while others will inevitably be dropped. The Apache philosophy is to add what's needed as and when it is needed.

   Friendly interaction between Apache and NCSA developers should ensure that fundamental feature enhancments stay consistent between the two servers for the foreseeable future.

6. Why didn't the Apache group wait for NCSA 1.4 ?

   we didn't expect the features we needed to show up in a near-term NCSA release. Furthermore, uncertainty over the future of the NCSA httpd license worried some of us. Apache is and will be a free server. With its collaborative development team we openly welcome new volunteers, suggestions and support.

7. OK, so how does Apache compare to other servers ?

   For an independent assessment, see http://www.webcompare.com/server-main.html

8. How thoroughly tested is Apache?

   Version 1.0 of Apache was 'plugged in' at,

   www.hotwired.com
     IRIX.
     Hits/day 400,000+
   us.imdb.com
     FreeBSD.
     Hits/day 800,000+
   www.ai.mit.edu
     SunOS.
     Hits/day 100,000+
   www.hyperreal.com
     BSDI.
     Hits/day 40,000+

   Also tested under HP-UX, Linux, SCO, Solaris, NeXT, .....

   See http://www.apache.org/info/apache_users.html for an incomplete list of sites running Apache.

   As you can see, these machines run services which are far busier than the average httpd server, so Apache has received a considerable workout. It works for us; however, this is beta code, and again, your mileage may vary.

9. What extensions does Apache offer over NCSA 1.3 ?

   Here are just some of the new features...

   Four ways of customizing error responses

     hard-coded responses, customizable text responses, local URL redirection, external URL redirection.

   Virtual-home

     A server running on a machine with multiple IP addresses can have a different home page for each IP address

   Additional CGI variables

     n.b. non-standard at the moment. The new CGI variables help scripts and server-side-includes be more aware of their environment and origin.

   Content negotiation

     Clients can negotiate the type of information they prefer, e.g. jpeg rather than gif, German instead of the default English, dvi instead of postscript.

     As clients improve in terms of user configurability, content negotiation will become a powerful and much system to give users what they want, instead of defaulting to some low common denominator.

   XBITHACK Last-modified:

     XBITHACK can be configured to send back a Last-modified: header to enable clients and proxies to cache documents which make use of XBITHACKed server-side includes.

   Better CGI script control

     CGI scripts can send back custom HTTP response headers as well as a body after an external redirect. An example of a custom response header,

         Status 404: URL was not found

   Improved logging of redirected URLs

     If a request results in a redirect to another URL, both URLs are logged in the access_log

   Multiple DirectoryIndex filenames

     Apache will search for index.html as well as any other filenames you prefer.

10. Does or will Apache act as a Proxy server?

    Apache version 1.1 and above will come with a proxy module. If compiled in, this will make Apache act as a caching-proxy server

11. What NCSA 1.3 bugs are fixed in Apache ?
    1. Efficiency...no longer does initgroups() or open_locale() on every connection, no longer does single- character read() system calls *ever*.
    2. Fixed a condition that was leading to un-killable httpd processes piling up on server machines and chewing up swap space.
    3. Unlimited numbers of Aliases and Redirects are allowed.
    4. AddTypes for the CGI and SERVER_INCLUDES magic MIME types are honored in .htaccess files.
    5. Auth_user is correctly logged for password-protected documents with server-side includes.
    6. Scripts can return Content-types with embedded blanks.
    7. Security hole allowing cgi script sources to be viewed, removed.
    8. Handling of redirects from scripts improved (no more mandatory three-second pauses on imagemap hits).
    9. XBITHACK also checks X-bits of included files.

12. What are the future plans for Apache ?

    - to continue as a public domain HTTP server,
    - to keep up with advances in HTTP protocol and web developments in general
    - to collect suggestions for fixes/improvements from its users,
    - to respond to needs of large volume providers as well as occasional users.

13. Who do I contact for support ?

    There is no official support for Apache. None of the developers want to be swamped by a flood of trivial questions that can be resolved elsewhere. Bug reports and suggestions should be sent to apache-bugs@mail.apache.org Other questions should be directed to comp.infosystems.www.servers.unix, where some of the Apache team lurk, in the company of many other httpd gurus who should be able to help.

    Commercial support for Apache is, however, available from a number third parties.

14. Is there any more information on Apache ?

    Indeed there is. See http://www.apache.org/.

15. Where can get Apache ?

    You can find the source for Apache at http://www.apache.org/.