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…
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.
VMware has just announced the release of vSphere 6.5 p01 (Patch ESXi-6.5.0-20170304001-standard). While there are a number of different issues addressed in the patch, there is one in particular that I wanted to bring to your attention. Automated UNMAP is a feature that we introduced in vSphere 6.5. This patch contains a fix for some odd behaviour seen with the new Automated UNMAP feature. The issue has only been observed with certain Guest OS, certain filesystems, and a certain block sizes format. KB article 2148987 for the patch describes it as follows: Tools in guest operating system might send unmap…
There has been a lot of discussion in the past around supported topologies for 2-node vSAN, specifically around where we can host the witness. Now my good pal Duncan has already highlighted some of this in his blog post here, but the questions continue to come up about where I can, and where I cannot place the witness for a 2-node vSAN deployment. I also want to highlight that many of these configuration considerations are covered by our official documentation. For example, there is the very comprehensive VMware Virtual SAN 6.2 for Remote Office and Branch Office Deployment Reference Architecture…
Last week, I had the pleasure of catching up with a new startup called Runecast. These guys are doing something that is very close to my heart. As systems become more and more complex, and with fewer people taking on more responsibility, highlighting potential issues, and providing descriptive guidance to resolving an issue is now critical. This is something that is resonating in the world of HCI, hyper-converged infrastructure, where the vSphere administrator may also be the storage administrator, and perhaps the network administrator too. This is where Runecast come in. Using a myriad of resources such as VMware’s Knowledgebase…
I spotted this announcement late on Friday afternoon (March 2nd). What is significant about this announcement is that this is the first ever Photon Platform/Controller release available on vmware.com. Previously you could only get it via Github. So what’s in this release? Well, first of all there is now a single SKU which provides you with ESXi, NSX-T, vSAN for Photon Platform as well the core Photon Platform Control plane, which comprises Lightwave, Photon OS and Photon Controller. The binaries for Photon Controller have been bumped up to v1.1.1. Regular readers will be aware that I have written a number…
Earlier this year, our colleagues in the US kicked off the “Getting More Out of vSAN” webcast series. We are pleased to be able to replicate this initiative in EMEA. We now have 2 webcast sessions lined up for the month of March: Session 1: vSAN Architecture & Tips and Tricks for 6.5, 14 March @ 10AM GMT This session provides an overview of vSAN’s architecture, policy based management and commonly used terms. We will also examine vSAN 2-node and stretched cluster configurations and some popular vSAN use cases. We will finish with an overview of new vSAN 6.5 features.…