The greatest challenge to any thinker is stating the problem in a way that will allow a solution

Bertrand Russell

Welcome to vBlog, a personal record of my techy tinkerings and particular ponderings.

I tend to focus on VMware virtualisation, and the interaction/automation of it using PowerCLI (VMware's PowerShell Snapin), but anything that I happen to stumble across that seems like it might be of use at a later date, may well get recorded here.

I also maintain vWiki, which was a predecessor to this blog. Wiki's are great for quickly recording snippets of info, but tend not to look that great; Blog's are better looking things, but seem to require more effort so that the posts/articles are accessible in their own right. As a result I tend to update both interchangeably as available time, and depth of thought, permit.

If you happen to find anything of use, or in need of correction please leave a comment. Knowing that my ramblings are of some use is a great reward; and similarly I'd hate to waste anybody's time by feeding them duff info.

See these pages for me info about me, and my vBlog, and below for my recent posts...

This script utilises a free 3rd party .NET library in order to be able to run SNMP queries from within PowerShell.  I created it in order to be able to keep track of the creation and usage of DHCP scopes during a migration project, and meant that I could instantly find out how short or not we were of available IP addresses.  Longer term you’d obviously want to set-up proper monitoring.

For more info on setting up the SNMP .NET library see my vWiki page – http://vwiki.co.uk/SNMP_and_PowerShell.  Its quite simple.  You have to download the binary package, extract and find the SharpSnmpLib.dll file, then load that into your PowerShell session and hey presto – you have SNMP functionality in PowerShell! Continue reading →

This post provides an example of how to gather some basic system info from an SNMP enabled host using PowerShell.

Why wouldn’t I use WMI?

You could in many circumstances.  In general the amount of information you can get from WMI is far greater than what’s available via SNMP, however,

  • In order to access WMI you often end up requiring full admin rights on the target systems, which is a security nightmare.
  • WMI is Windows platform dependant, whereas SNMP is normally available for any enterprise device.

Continue reading →

A while back I discovered a SNMP .NET offering that (given that PowerShell is .NET) meant that I could use PowerShell as a SNMP client, which I’ve documented on my Wiki – http://vwiki.co.uk/SNMP_and_PowerShell.

At the time my intended aim for the ability disappeared, and so I never really got to put into use.  This post brings together a couple of techniques in order to achieve regular SNMP polling of a device.  The results of which go into an RRD database (you don’t need to do this, what you do with the results of the SNMP polls is up to you). Continue reading →