My DockerCon 2017 Day #1

This is my very first DockerCon. It is also the first time that I’ve attended a conference purely as an attendee, and not have some responsibilities around breakout sessions, or customer meetings. Obviously I have an interest in much of the infrastructure side of things, so that is where I focused. This post is just some random musings about my first day at DockerCon17, and some things that I found interesting. I hope you do too.

A closer look at Cohesity 4.0

Last week, I had a chance to catch up with my pal, Rawlinson Rivera. Rawlinson and I worked closely on a lot of storage related stuff at VMware, but he has since moved on to pastures new, and is currently the CTO for the Global Field over at Cohesity. I’ve written about Cohesity a number of times on this blog. I think the first time I wrote about them was during VMworld 2015, just before the 1.0 product launched, and they were still pitching the idea of secondary storage and how they would take care of things like snaps, clones,…

Erasure Coding and Quorum on vSAN

I was looking at the layout of RAID-5 object configuration the other day, and while these objects were deployed on vSAN with 4 components, something caught my eye. It wasn’t the fact that there were 4 components, which is what one would expect since we implement RAID-5 as a 3+1, i.e. 3 data segments and 1 parity segment. No, what caught my eye was that one of the components had a different vote count. Now, RAID-5 and RAID-6 erasure coding configurations are not the same as RAID-1. With RAID-1, we deploy multiple copies of the data depending on how many…

What’s new in vSAN 6.6?

vSAN 6.6 is finally here. This sixth iteration of vSAN is the quite a significant release for many reasons, as you will read about shortly. In my opinion, this may be the vSAN release with the most amount of new features. Let’s cut straight to the chase and highlight all the features of this next version of vSAN. There is a lot to tell you about. Now might be a good time to grab yourself a cup of coffee.

Debunking some behavior “myths” in 3 node vSAN cluster

I recently noticed a blog post describing some very strange behaviors in 2-node and 3-node vSAN clusters. I was especially concerned to read that when they introduced a failure and then fixed that failure, they did not experience any auto-recovery. I have reached out to the authors of the post, just to check out some things such as version of vSAN, type of failure, etc. Unfortunately I haven’t had a response as yet, but I did feel compelled to put the record straight. In the following post, I am going to introduce a variety of operations and failures in my…

Sizing for large VMDKs on vSAN

I’ve recently been involved in some design and sizing for very large VMDKs on vSAN. There are a couple of things to keep in mind when doing this, not just the overhead when deciding to go with RAID1, RAID5 or RAID6, but also what this means for component counts. In the following post, I have done a few tests with some rather large RAID-5 and RAID-6 VMDKs, just to show you how we deal with it in vSAN. If you are involved in designing and sizing vSANs for large virtual machines, you might find this interesting.