Thanks to our friends over at EMC (shout out to Itzik), we’ve recently been made aware of a limitation on our UNMAP mechanism in ESXi 5.0 & 5.1. It would appear that if you attempt to reclaim more than 2TB of dead space in a single operation, the UNMAP primitive is not handling this very well. The current thought is that this is because we have a 2TB (- 512 byte) file size limit on VMFS-5. When the space to reclaim is above this size, we cannot create the very large temporary balloon file (part of the UNMAP process), and…
Followers of my blog will have seen a number of articles posted recently about storage vendors that I managed to catch up with at this year’s VMware Partner Exchange in Las Vegas. In the last in this series of articles, I managed to spend some time with the folks from GreenBytes. The timing was very opportune, as GreenBytes just made a major announcement to their portfolio, namely their new vIO, the virtual storage appliance version of their IO Offload Engine solution for desktop virtualization. I met up with Michael Robinson (VP, Marketing), Jeff Eberhard (Sr. Systems Engineer) and Steve O’Donnell…
Another storage vendor that I finally managed to catch up with at this year’s VMware Partner Exchange was Tegile. I was curious about the name, and I learnt that Tegile was a merging of the terms Technology and Agility. Tegile is another vendor that I have seen at various events, but have not had an opportunity to catch up with them in person and learn about their products. This time, I got an opportunity to catch up with Rob Commins (VP of Marketing) and Mike Recker of Tegile, and put a few questions to them.
Last week, I was at our VMware Partner Exchange event in Las Vegas. Apart from my own break-out session on vSphere 5.1 storage features, I wanted to catch up with a number of our partner vendors who are doing cool things in the storage space. One of these vendors is Dot Hill, a company from Longmont, Colorado, who have been making storage arrays for a considerable amount of time now, but one which does not seem to get a huge amount of exposure. I caught up with Matt Alsip, the Technical Marketing Manager at Dot Hill, to put my customary…
Hi all, Prior to the holidays, VMware released new versions of vCenter & ESXi on December 20th. There were new releases for both vSphere 5.0 & 5.1. In this post, I want to discuss release 5.0 Update 2. There were a number of notable fixes specific to storage which I wanted to highlight. I will follow-up with a look at storage enhancements in the new 5.1 release in a future post.
I recently received a question about the following message appearing in the VMkernel logs of an ESXi host: 2012-12-07T12:15:58.994Z cpu17:420151)ScsiDeviceIO: 6340: Could not detect setting of sitpua for device naa.xxx. Error Not supported. So what does that mean? Firstly, it isn’t anything to be greatly concerned about. SITPUA, short for Single Initiator Thin Provisioning Unit Attention, is related to Out Of Space (OOS) conditions on Thin Provisioned LUNs. To ensure that an Out Of Space (OOS) warning is sent to just one host using the affected LUN, the SITPUA bit in the Thin Provisioning Mode Page must be set to…
Welcome to part 3 of the NFS Best Practices series of posts. While part 1 looked at networking and part 2 looked at configuration options, this next post will look at interoperability with vSphere features. We are primarily interested in features which are in some way related to storage, and NFS storage in particular. While many of my regular readers will be well versed in most of these technologies, I’m hoping there will still be some items of interest. Most of the interoperability features are tried and tested with NFS, but I will try to highlight areas that might be…