Name: Chris Rigby
Email: [EMAIL PROTECTED]
Preferred User ID: rigbyc
Hi there. I have written a small Apache module which allows
a web developer to embed SNMP get statements directly into
HTML code. It uses the current SNMP perl module from CPAN,
parses an HTML document, performs the necessary SNMP
connections, and returns the dynamic information, all from a
plain HTML page. I would like to post it to the archive to see
if there is any interest in it, as well as to get any critical feedback
and ideas concerning its development.
I have tentatively named the module WebSNMP.
Here is the README file:
---------------- start README
-------------------------------------------
WebSNMP is a perl module for Apache Web Servers that allows
a web developer to easily insert snmp functionality into web
pages with simple html tags. Please use
perldoc Apache::WebSNMP
for a detailed description.
PLEASE NOTE: This module REQUIRES the perl SNMP module, which
can be downloaded from :
www.cpan.org
To install the module, simply do the usual:
perl Makefile.PL
make
make install
After this, you must add the following entry to your httpd.conf
file:
<Location /directory_name>
SetHandler perl-script
PerlHandler Apache::WebSNMP
</Location>
where "directory_name" is the location in your DocumentRoot
where you wish to put all of your snmp web documents. Then
simply restart your web server and you are ready to go!
Please direct any questions or comments to:
[EMAIL PROTECTED]
Thanks for trying WebSNMP!
---------------------- end README ----------------------------------
I have also written the beginnings of a perldoc for it:
-----------------------begin perldoc
------------------------------------
NAME
Apache::WebSNMP - Allows for SNMP calls to be embedded in
HTML
SYNOPSIS
<html>
<body>
<snmp>
host=zoom.google.org
community=public
connect
interface=ifDescr
extension(interface)=2
mac=ifPhysAddress
extension(mac)=2
query
</snmp>
The interface <b>descriptor</b> for the ethernet card is <snmp>
print(interface) </snmp>
and its <b>mac address</b> is <snmp> print(mac) </snmp>
</body>
</html>
DESCRIPTION
The WebSNMP module allows one to embed SNMP commands
directly into HTML code.
REQUIRES
This module requires the perl SNMP module, available at
the CPAN site.
USAGE
The module allows for three different kinds of statements,
surrounded by <snmp> and </snmp> html tags. The three
types of statements consist of configurations, variable
assignments, and commands. A brief description of each
type of statement follows:
Configuration
The configuration statements allow the user the set which
host to poll for SNMP information, as well as the SNMP
community that the get statements will draw from. This
essentially takes the form of assigning values to the
reserved variables host and community. All variables are
assigned with the following syntax:
varible_name=value
Note: there must not be any intervening whitespace between
the '=' and the name and value. Thus to set the SNMP host
to machine.domain.net, we would issue the configuration
statement:
<snmp>host=machine.domain.net</snmp>
If not specified, the default host is localhost, and the
default community is public.
Variable Assignments
Variables are used as temporary holding locations for
information returned from SNMP calls. The decision to use
variables was made to obviate the necessity of making a
different SNMP get call for each separate piece of
information. Variable assignments follow the simple
format listed above, where the variable and the value,
this time the symbolic name of a SNMP object identifier,
are separated only by an equals sign (no whitespace). For
example: description=ifDescr The OIDs currently
implemented are a subset of the IETF Management MIB.
Support is available for the system, interface, ip, tcp,
udp, icmp, and at modules. A list of the currently
supported OIDs, and their symbolic equivalents, is given
below:
# system
'sysDescr' => "1.3.6.1.2.1.1.1",
'sysObjectID' => "1.3.6.1.2.1.1.2",
'sysUpTime' => "1.3.6.1.2.1.1.3",
'sysContact' => "1.3.6.1.2.1.1.4",
. . . . . . . .
'icmpOutTimeExcds' => '1.3.6.1.2.1.5.17',
'icmpOutParmProbs' => '1.3.6.1.2.1.5.18',
'icmpOutSrcQuenchs' => '1.3.6.1.2.1.5.19',
'icmpOutRedirects' => '1.3.6.1.2.1.5.20',
'icmpOutEchos' => '1.3.6.1.2.1.5.21',
'icmpOutEchoReps' => '1.3.6.1.2.1.5.22',
'icmpOutTimestampsReps' => '1.3.6.1.2.1.5.23',
'icmpOutTimestampsReps' => '1.3.6.1.2.1.5.24',
'icmpOutAddrMasks' => '1.3.6.1.2.1.5.25',
'icmpOutAddrMaskReps' => '1.3.6.1.2.1.5.26',
For example, to get the number of outbound and inbound
errors on an ethernet interface, we would assign the
ifOutErrors and ifInErrors OIDs to variables. Thus:
<snmp> errorin=ifInErrors errorout=ifOutErrors </snmp>
Note that more than one command can be nested inside a
single set of <snmp> tags, as long as they are separated
by whitespace.
Commands
The following command statements are currently available:
connect initiates a connection with the SNMP host defined
with the host configuration statement. This statement can
be can be utilized multiple times in order to connect to
several different machines, however any queries sent will
be sent to the current connection.
query actually initiates the SNMP get for the information
you have requested in your variables, contacting the host
defined by the host configuration command, and storing the
data in the proper variable.
extension(variable_name) adds an extension to the OID
named by variable_name. Most OIDs require some form of
extension (for example, the 'system' OIDs usually require
an extension of 0, while interface OIDs require the
interface number as an extension). The extension is
merely appended to the OID value contained in the named
variable.
print(variable_name) simply prints the information
returned to a variable after a query command.
EXAMPLE
To put all this together, let us take a simple example:
we wish to retrieve information concerning the ethernet
interface on a host named 'host.domain.net'. Primarily we
are concerned with the administrative status, mac address,
and bytes transferred in and out of the interface. We
would begin with the following block:
<snmp>
host=host.domain.net
community=public
connect
</snmp>
This block defines the host and the SNMP community, and
actually makes the connection to the host. This block can
be placed anywhere within your HTML document, as long as
it comes before your SNMP queries. Next, we must define
the information that we wish to obtain:
<snmp>
description=ifDescr
extension(description)=2
mac=ifPhysAddress
extension(mac)=2
inbytes=ifInOctets
extension(inbytes)
outbytes=ifOutOctets
extension(outbytes)
query
</snmp>
This block instantiates four variables: description, mac,
inbytes, and outbytes, in which the information we wish to
obtain will be stored. The extension commands tell the
program that we are interested in interface 2. Finally,
the query statement performs the SNMP get on the connected
host. All that remains is to print out our data. Let us
put it in tabular format:
<table>
<tr>
<td>
Description
</td>
<td>
Mac Address
</td>
<td>
Bytes In
</td>
<td>
Bytes Out
</td>
</tr>
<tr>
<td>
print(description)
</td>
<td>
print(mac)
</td>
</td>
<td>
Bytes In
</td>
<td>
Bytes Out
</td>
</tr>
<tr>
<td>
print(description)
</td>
<td>
print(mac)
</td>
<td>
print(inbytes)
</td>
<td>
print(outbytes)
</td>
</tr>
</table>
This block merely prints out our information as an HTML table.
Mission accomplished.
AUTHOR
Chris Rigby
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Please let me know if this would be of interest.
Look forward to hearing from you.
Thanks,
Chris Rigby
