OSS_SNPM

OSS_SNMP

A PHP SNMP Library for People Who HATE SNMP, MIBs and OIDs!

I (Barry O'Donovan) hate SNMP! But I have to use it on a daily basis with my company, Open Solutions.

Don't get me wrong, it's an essential tool in the trade of network engineering but it's also a serious PITA. Finding MIBs, OIBs, making them work, translating them, cross-vendor translations, etc, blah, blah. And then, when you do find what you need, you'll have forgotten it months later when you need it again.

Anyway, while trying to create some automatic L2 topology graphing tools (via Cisco/Foundry Discovery Protocol for example) and also some per VLAN RSTP tools to show port states, I started writing this library. As I wrote, I realised it was actually very useful and present it here now in the hopes that the wider network engineering community will find it useful and also contribute back MIBs.

Documentation

Please see the wiki.

Example Usage

First, we need to instantiate an SNMP object with a hostname / IP address and a community string:

$ciscosw = new \OSS_SNMP\SNMP( $ip, $community );

Assuming the above is a standard Cisco switch, let's say I want to get an associate array of VLAN names indexed by the VLAN ids:

print_r( $ciscosw->useCisco_VTP()->vlanNames() );

This yields something like the following:

Array
(
    [1] => default
    [2] => mgmt
    [100] => cust-widgets
    [1002] => fddi-default
    ...
)

It really is that easy. As another example, if you wanted to get the system contact:

echo $ciscosw->useSystem()->contact();

License

This software library is released under the New BSD License (also known as the Modified BSD License). See the LICENSE file or the header of all other files for the full text.

The Bad News... with some Good News

The, what I'm calling, MIBs are defined in OSS_SNMP/MIBS and these define the functionality as per the examples above.

There's only a handful of MIBs currently defined - essentially what I've needed so far for other projects.

But it's really easy to add your own. And please send me a pull request for those.

For the MIBs I've written, only Iface (MIBS/Iface.php) is fully complete and I just completed it as an exercise to help future contributors. But there's some really useful functionality in the others. For example the Cisco/CDP MIB can discover your entire L2 network topology recursively. Another project we've released, NOCtools, give concreate examples of this with GraphViz.

PHP 5.4 is a requirement. Yeah, I know. Not even the current Ubuntu ships this. But look, 5.4 is released, it's stable, it's available on FreeBSD and from personal ports for Ubuntu.

The reason for 5.4, among other things, is that we can now dereference an array directly from a function call:

$name = $ciscosw->useCisco_VTP()->vlanNames()[ $vlanid ];

rather than the old way:

$vlanNames = $ciscosw->useCisco_VTP()->vlanNames();
$name = $vlanNames[ $vlanid ];

And as most of the defined MIBs walk a given tree, almost all defined functions return an array.

Right now it's SNMP v2. This can be easily updated for multiple version support. Also, it's read only as, at time of writing, I have no requirement to set SNMP values.

Code / phpDoc Documentation

Documentation can be generated from the root directory by executing:

./bin/phpdoc.sh --force

and it will be found under the doc/ directory. There is an online version available here.