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Showing posts from September, 2018

NSX Section Based Distributed Firewall Model

I've written before about creating NSX Distributed Firewall Rules following a model that uses rules that will specifically hit traffic based on if it's Inbound or Outbound.  That model is also useful for creating NSX Security Policies, as there's no negative logic (NOT applied to object) in the rule set.  While that model works great, it can be a bit difficult to wrap your head around.  In turn, that can make it difficult to hand off to a customer... so we've been working on an alternate model.

Unfortunately, this model does not work with Service Composer Policies, but it's flexible enough that it doesn't really need them.  It's based on a set of generic Security Tags (with corresponding Security Groups), that interact to create a dynamic micro-segmentation solution.  This model is based on defining a set of DFW Sections, each of which serves a very specific purpose in blocking or allowing traffic.  When creating new firewall rules, the administrator only n…

Pulling Average VM Network Usage En Masse

One of my customers is considering moving some of their infrastructure around and wanted to get an idea about how their WAN connection might be impacted by the move.  They didn't have vROPS and we didn't want to enable greater vCenter logging due to space constraints on the SQL server (that tells you that we're working with some older systems, doesn't it!).  So, I decided that our best course of action would be to write a script that could run on an interval, collecting and summarizing the real-time statistics that we actually needed.  Hence the creation of summarize-VMNetUsage.ps1!

This is a pretty straightforward script.  If you run it without any parameters, it will find the highest 20 second Average Network Usage stats from all VMs in an environment, then return a summary of its findings: VM Count, sum, average, maximum, minimum, and a date-stamp.  Then, the script enters a holding pattern until 1 hour has passed and it starts the process again.  It does this for 2…