README file v 2.20
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ROUTERS.CGI  : Frontend to RRDTool databases created by MRTG
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Author: Steve Shipway (steve@steveshipway.org)

Note: if you are experiencing problems with running routers.cgi, take a look
      at the PROBLEMS file for more help. It's in the doc directory.

      If you want help using a particular feature, check the doc/HOWTO file.

      If you want help installing, look at the doc/INSTALL file

      If you want to know about MRTG file directives, look at the doc/MRTG_INFO 
      file.

      If you want to know about configuring routers.cgi, then look at 
      the doc/ROUTERS_CONF file.
 
      If you are upgrading, and want to know the new features and bug fixes,
      then take a look at the doc/UPGRADING and CHANGES files.

Acknowledgement:
      The SNMP_Session.pm, SNMP_util.pm and BER.pm files accompanying this
      package are not created by myself.  They are as distributed with the
      current MRTG release from Tobi Oeticker, and contain their own
      attribution.  They are not required for the routers.cgi package to run,
      they are used only by the targetnames.pl script.

Quick Install
-------------
For more details, look at doc/INSTALL.  However, if you just want to go for it,
then run the Perl script install.pl and follow the prompts.

Summary
-------
This package consists of a single Perl CGI script, and a number of GIF 
images.  Both the images and script need to be accessible from your web 
browser in order for the package to work.  In addition there is a setup
script, a script to help configure your .conf file, and an addin script
to give routing tape information.

This gives a new, forms-enhanced frontend for the RRDTool databases.  It is
intended to replace the '14all.cgi' script shipped with RRDTool and MRTG,
for certain applications.

What it does
------------
It generates some compact, fairly good-looking frames-based pages to act as
frontends for the router statistics collected by MRTG and held in the RRDTool 
databases, as configured in the MRTG .conf files.  Although highly configurable,
it is designed to work with minimum configuration using AI code to take
reasonable defaults for most options.

What it does not do
-------------------
It will not work with MRTG .log files.  It will not work with other RRDTool
databases not created by MRTG. 
It will not collect the data, it will only display it (except in the case
of the routingtable addin).

What it looks like
------------------
Hopefully, there will be links to demo pages from the main website, on
http://www.steveshipway.org/software/

Why does it do/not do this?
---------------------------
I wanted a frontend that was user-friendly and easy to move to.  A more
general frontend would necessarily be more complex to configure, and would
not be so user-friendly (if you want something like this, see the excellent
Cricket frontend).
I found that 90% of the statistics I needed access to were for routers, 
collected by the MRTG software.  So, making the appropriate assumptions, I
found I could use the existing MRTG configuration files and save on unnecessary
work.

How does it decide what names to give routers and interfaces?
-------------------------------------------------------------
Device names are chosen in this order of preference:
1. The [targetnames] section of the routers.conf files, using the .conf file
   name as a key (without the path) (deprecated)
2. The old [routerdesc] section of the routers.conf file, using the name in 4.
   below as a key.  This is now deprecated.
3. The first ShortDesc[] directive for the first target in the MRTG .conf file
4. The first word of the first Title[] line in the MRTG .conf file
5. The filename containing the data

Target Long descriptions - 
1. [targettitles] section of routers2.conf (deprecated)
2. routers.cgi*Description[xxxx]: xxxxx
3. Title[xxxx]: xxxxx

Target Short descriptions -
1. [targetnames] section of routers2.conf (deprecated)
2. routers.cgi*ShortDesc[xxx]: xxxxxxx
3. SetEnv[xxxx]: MRTG_INT_DESC="xxxxxx"
4. If ifdefault=target is set in routers2.conf [targetnames] section, or 
   ifdefault is undefined, then use IP Address, Interface desc, #interface 
   number, or the target name itself (in that order)
5. If ifdefault=cfgmaker is set in routers2.conf [targetnames] section, then 
   use the PageTop section defined by cfgmaker to find and use PortName, 
   Description, or IfName (in that order)
6. If a MRTG .ok file exists with an entry for this target's interface, then 
   the description associated with that interface.
7. Use the long description, possibly truncated to the first word or the first 
   word after the last colon if it contains a colon.

Router group names are set as:
1. The [targetnames] section of the routers.conf, using the full directory
   name as a key (case sensitive, NT users should add the drive letter if it
   is specified in the confpath directive)
2. The last component of the directory name, often with a trailing /

95th Percentile Calculations
----------------------------
In brief, they are inaccurate, and this cannot be corrected.
The 95th Percentile is a weighted Median average.  Simply put, it is the 
minimum value that the sample set remains below 95% of the time.  A true
Median average could also be thought of as the 50th Percentile.
Unfortunately the RRDTool databases work on a Mean average.  As the sample
interval increases (ie, you move from Daily graphs to Weekly graphs, and so
on) you will smooth out the data.  This results in a lower 95th Percentile
number than it should be.  This is unavoidable because of the lossy nature
of the RRDTool databases - they summarise in order to save space.  Sadly this
summarising is not compatible with the calculation of the 95th Percentile.
So, if you want a more meaningful 95th Percentile, look at the daily graphs,
where the samples are averaged only over 5min intervals.
Other ways to get more meaningful 95th Percentile numbers are to decrease
the sample interval to 1min, and to double the RRA length of the RRD files
(you can do this with the rrdextend.pl script in the extras directory).
The new v1.3 of RRDtool has built-in support for accurate 95th Percentile
calculations, if you manually add an extra RRA to the database.  Routers2
does not yet take advantage of this, though.

Routing Tables
--------------
If you set the appropriate option in the routers.conf file, then a new link
will appear on the 'info' page giving the router's routing table.  However,
for this to work you must:
* Install Net::SNMP on your server
* Install the routingtable.cgi script
* Make sure your routers will allow this server to make SNMP queries 
* Uncomment the option in the routers.conf
In addition, the MIME multipart support in IE4 and IE5 is broken, and does not
usually work correctly.  It's OK with Netscape though!  The script detects
the existance of IE, and disables the server push update, so it works but is
not so pretty.

Grouping of routers
-------------------
This feature is disabled by default, but you can switch it on in the 
routers.conf file.  When enabled, the routers are grouped according to the
directory in which their correcponding MRTG .cfg file lives.  You can define
files in more than one directory by having multiple entries on the 'cfgfiles'
directive, eg:
cfgfiles = dir1/*.cfg dir2/*.cfg
and so on.  You can set a better description for these groups by making an
entry in the [targetnames] section of the routers.conf file.
See the HOWTO file for more detailson this feature.

Timezones
---------
Support for different timezones is patchy, due to O/S problems.  Basically,
under UNIX you will find the Timezone[] directive mostly works, although
you may need to use a more specific syntax.  Under Windows, it is more
difficult and you may not be able to place routers into different timezones,
nor will you be able to show graphs relative to any timezone but the one the
server lives in (this can be overridden on a GLOBAL basis in the routers.conf
file).  See the HOWTO for more information.  Note that MRTG under Windows can
cope better with Timezones than RRDTool as it uses a different (better) C
compiler for the library.  Sadly we are stuck with the current RRDTool
library limitations with timezones.

Trend Analysis
--------------
To do this, you need to install the trend.cgi script in the extensions
directory into your cgi-bin.  Full instructions are given in the accompanying
documentation.  You need to add directives to your MRTG .cfg files to link
this script in as an extension to the various targets.

Which MRTG .cfg file directives are supported?
----------------------------------------------
See the file MRTG_INFO for a complete list.

I have a few ideas...
---------------------
If they are relating to MRTG or RRDTool, then send them to Tobi Oetiker (the
author of RRDTool).  For this frontend, then by all means email me.  I'd like
to know if anyone else is using this.

There's a bug!
--------------
If you find a bug, or something that doesn't work in your setup, then remember
that this is a work in progress.  Email me and let me know how/if you fixed it,
and what you think should be done to correct it.  All bug reports are read, 
and discussion happens on the mailing list.  So far, most bugs have been 
fixed very soon after reporting.  
There is a discussion forum and bug reporting centre on steveshipway.org:
http://www.steveshipway.org/forum
The mailing list currently lives on steveshipway.org, to join go to the URL
http://www.steveshipway.org/support

More information
----------------
There is a book available, _Using MRTG with RRDtool and Routers2_.  This gives
detailed information on planning, setting up, configuring and tuning your
MRTG system.  See http://www.steveshipway.org/book/ for more details.

Saying Thanks
-------------
If you want to thank me for giving away this software, then there is an easy
way to do it - send me a DVD or similar gift from my Amazon wishlist.
See the page on
http://www.steveshipway.org/software/wishlist.html
for more details on how to show your appreciation.  
Also, Tobi (who of course produced MRTG and RRDTool) has a similar scheme
for his DVD collection, and you could do worse than sending him a gift as well.

Legal Jargon
------------

In summary, you can use it, copy it, modify it and give it away, but not
sell it or any derivative work.  More precisely, see the following GPL
text:

routers.cgi : Interactive web frontend to RRDTool routers traffic database
Copyright (C) 2000-2009 Steve Shipway

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.