VM Zombie Survival Guide (Part 1)
Administrators unite against the great VM Zombie menace! Long have we toiled to create the pillars of virtual infrastructure! We plan, and overcommit, and squeeze every last resource out of our designs, our environments, our data centers. And yet, we still face a considerable foe in wasted resources. Zombies!
How many times have you stood up a new environment, and migrated VMs, only to come across an old crusty Windows 2000 Advanced Server with Pervasive SQL (oh god, btrieve!) that still lurks in the lower regions of your vm sprawl. Yes, this lower denizen, or Zombie, had its roots in good intentions. You see, in the olden days, VMs sprung into consciousness for all sorts of development duties. However, due to a lack of regulation, and attention, they began to languish. Further, these zombie’s could be multi-headed (from decaying snapshots) and fiendishly hungry (4 vcpu’s for your cold fusion vm or 8GB ram for your 3 SQL instances that just have to mimic production). Before we dig out the shotgun and gas up the chainsaw, let’s look at the characteristics of a VM Zombie.
Know your Enemy: ZOMBIES!
First, it’s important to understand the distinction between a VM Zombie and a Zombie process. Think of them as greater and lesser zombies. A VM Zombie is a virtual machine that has been left to suck resources, yet perform no real task. Its idle hands merely wish to be used to devour tasty ram and cpu cycles. Let it also be known that VM Zombies can drop chunks of body parts (folders/vmdk/files) on your storage array as they stumble through your environment. Gross! A zombie process on an ESX host is a process that is dead, and you cannot kill the dead. We will be focusing on the VM Zombies, so grab your laptop (blunt object trauma!), survival rations (beer), and let’s learn about Virtualization’s Great Menace!
To kill zombies, we need tools. Big, sharp, loud, gunpowder-based tools. We’ve got two two great tools on tap: one paid and one free that I turn to in times of the undead feasting on the living flesh of my hosts. These tools are well known in the community and lots of information can be found about them.
VKERNEL – Optimization Pack
VKernel make a number of excellent tools, both paid for and free. When it comes to quality for decapitation of the Zombie Menace, I have to say I am very pleased with what this application brings to the table. First and foremost, as your virtual infrastructure scales (and sometimes sprawls), it can lead to lots of Zombie action. Wastefinder (a part of this pack) is absolutely brilliant J Not only does it help you find the roving Zombie hoard (snapshots included), it provides the empirical and historical data to validate. This goes hand in hand with rightsizing VMs, which can be troublesome if you get pushback from application owners, management, etc. Virtualizetips.com has had the privilege of previewing these tools, and I agree that their Gold award from VMworld 2010 is well deserved. Take that you brain-slurping bastards!
I have been using this tool in my home lab for quite some time, and also in my various locales of employ. Being free, this is a very solid app for tracking down zombie bits (both hunks of dead flesh on your storage array, and also snapshots and unregistered, rogue VMs). It will also export in a nice CSV format so you excel nerds can get your game on. I really like the quick and dirty view of an environment. It lets me zoom in and get what info I want quickly. At a glance, you get so much more also: build numbers, VMware Tools levels on your VMs, and all the hardware content for your VMs. This is a great keep-on-the-laptop tool if you have many clients to visit and need to get a quick assessment of their hotspots.
Coming in Part 2, more tools, tips, and survival tips to bring the fight to the Zombie Horde! Groovy!