I (Barry O'Donovan) hate SNMP! But I have to use it on a daily basis with my company, Open Solutions and our customers.
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 which has turned out to be very useful. It is presented here in the hope that the wider network engineering community will find it useful and also contribute back MIBs.
Please see the wiki.
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();
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, 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, Iface (MIBS/Iface.php) is fully complete as an example
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.
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 current requirement to set SNMP values via PHP.
PHP 5.4 is a requirement. The reason for 5.4 (besides the fact it's long been regarded as stable), 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.
The only other requirement is the php5-snmp library.
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.