Migrations and Virtual Volumes – Deep Dive

VVolsRecently I published an article on Virtual Volumes (VVols) where I touched on a comparison between how migrations typically worked with VAAI and how they now work with VVols. In the meantime, I managed to have some really interesting discussions with some of our VVol leads, and I thought it worth sharing here as I haven’t seen this level of detail anywhere else. This is rather a long discussion, as there are a lot of different permutations of migrations that can take place. There are also different states that the virtual machine could be in. We’re solely focused on VVols here, so although different scenarios are offered up, I highlight what scenario we are actually considering.

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VSAN considerations when booting from USB/SD

This is a conversation that comes up time and time again. It’s really got to do with the following considerations when booting an ESXi host that is participating in VSAN from an SD/USB device::

  1. What should I do for persisting the vmkernel logs?
  2. What should I do about persisting the VSAN trace files?
  3. What should I do for capturing core dumps (PSOD)?

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vSphere 6.0 Storage Features Part 6: action_OnRetryErrors

In vSphere 6.0, an improvement has been made to how we handle I/O issues, such as flaky drivers, misbehaving firmware, dropped frames, fabric disruption, dodgy array firmware, and so on which can cause I/O failures. The issue is that, previously, we continually retry these sorts of I/O errors, which can lead to all sorts of additional problems. In this release we are changing our behaviour for marking a path dead.

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A closer look at SpringPath

springpathAnother hyper-converged storage company has just emerged out of stealth. Last week I had the opportunity to catch up with the team from SpringPath (formerly StorVisor), based in Silicon Valley. The company has a bunch of ex-VMware folks on-board, such as Mallik Mahalingam and Krishna Yadappanavar. Mallik and Krishna were both involved in a number of I/O related initiatives during their time at VMware. Let’s take a closer look at their new hyper-converged storage product.

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vSphere 6.0 Storage Features Part 5: Virtual Volumes

VVolsI pushed this post out a bit as I know that there is a huge amount of information out there around virtual volumes already. This must be one of the most anticipated storage features of all time, with the vast majority of our partners ready to deliver VVol-Ready storage arrays once vSphere 6.0 becomes generally available. We’ve been talking about VVols for some time now. Actually, even I have been talking about it for some time – look at this tech preview that I did way back in 2012 – I mean, it even includes a video! Things have changed a bit since that tech preview was captured, so let’s see what Virtual Volumes 2015 has in store.

Much kudos to my good friend Paudie who did a lot of this research.

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vSphere 6.0 Storage Features Part 4: VMFS, VOMA and VAAI

VMFSThere was a time when VMFS was the only datastore that could be used with ESXi. That has changed considerably, with the introduction of NFS (v3 and v4.1), Virtual Volumes and of course Virtual SAN. However VMFS continues to be used by a great many VMware customers and of course we look to enhance it with each release of vSphere. This post will cover changes and enhancements to VMFS in vSphere 6.0.

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vSphere 6.0 Storage Features Part 3: MSCS Improvements

icon_clusterOK – not storage improvements per-se, but I got into the habit of documenting our Microsoft Clustering Services (MSCS) improvements some time back, and habits die-hard. Many of our customers continue to run Microsoft Clustering Services (MSCS) on top of vSphere. This is well-recognized, and VMware continues to improve and add features around this for our customers. vSphere 6.0 is no different, with a selection of improved functionality around MSCS on vSphere.

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