On a recent trip to VMware in Palo Alto, I found some time to visit with a good pal of mine, Vinay Gaonkar, who is now the Product Manager for XtremIO over at EMC. Vinay used to be a storage PM at VMware (he worked on the initial phases of VVols), and we worked together on a number of storage items in various vSphere releases. It’s been almost 2 years since I last spoke to the XtremIO folks (VMworld 2012 in fact, when the product still had not become generally available), so I thought that this would be a good…
I’ve done a few posts in the past which discuss the VM Home Namespace object. To recap, the VM Home Namespace is where we store all the virtual machine configuration files, such as the .vmx, .log, digest files, memory snapshots, etc. I also highlighted that the VM Home Namespace is limited to 255GB in size. This led one reader to raise the following observation: It means that it is not possible to do a snapshot with memory for a VM with 256 GB of RAM. This is indeed correct. If you attempt to snapshot a VM (with memory) that has…
A couple of weeks ago the electronic version of Essential Virtual SAN was published and this week the first paper copies started shipping! Because of that, Duncan and I decided we will give away 4 e-books each. If you want to win one then please let us know why you feel you deserve to win a copy using the hashtag #essentialvirtualsan on twitter. Duncan and I will decide which 8 tweets will win an eBook, and of course we will favor the ones that make us laugh – it’s as simple as that! So just to be clear: Tweet why you…
I just learnt this morning that the paper edition of the Essential Virtual SAN (VSAN) book that I wrote with my colleague and good pal Duncan Epping is now available. The e-book and kindle versions were available a couple of weeks ago, but its great to see the paper edition hit the shelves. The book will hopefully have all you need to get you up and running with VSAN, including architecture details and design considerations. We tried to include everything that someone involved in VSAN administration would need. I can now appreciate the time and effort that authors put into…
I was involved in an interesting thread recently with one of our VSAN partners regarding disk sizes used in VSAN, and what impact smaller drives may have. In an earlier post, I discussed reasons why VSAN would stripe a VMDK storage object even though a stripe width was not requested in the VM Storage Policy – Why is my Storage Object striped? In that post, I highlighted the fact that if the VMDK storage object is too big to fit onto the free space of a single hard disk, then it will automatically be striped across multiple hard disks. However…
I was in a conversation with one of my pals over at Tintri last week (Fintan), and he observed some strange behaviour when provisioning VMs from a catalog in vCloud Director (vCD). When he disabled Fast Provisioning, he expected that provisioning further VMs from the catalog would still be offloaded via the VAAI-NAS plugin. All the ESXi hosts have the VAAI-NAS plugin from Tintri installed. However, it seems that the provisioning/cloning operation was not being offloaded to the array, and the ESXi hosts resources were being used for the operation instead. Deployments of VMs from the catalogs were taking minutes…
I’m a bit late in bringing this to your attention, but there is a potential issue with VASA storage providers disconnecting from vCenter resulting in no VSAN capabilities being visible when you try to create a VM Storage Policy. These storage providers (there is one on each ESXi host participating in the VSAN Cluster) provide out-of-band information about the underlying storage system, in this case VSAN. If there isn’t at least one of these providers on the ESXi hosts communicating to the SMS (Storage Monitoring Service) on vCenter, then vCenter will not be able to display any of the capabilities…