About a year ago I wrote an article stating that Raw Device Mappings (RDM) continued to rely on LUN IDs, and that if you wished to successfully vMotion a virtual machine with an RDM from one host to another host, you had to ensure that the LUN was presented in a consistent manner (including identical LUN IDs) to every host that you wished to vMotion to. I recently learnt that this restriction has been lifted in vSphere 5.5. To verify, I did a quick test, presenting the same LUN with a different LUN ID to two different hosts, using that…
In a post on the vSphere blog, I spoke about how to use maintenance mode. As a follow on request, a number of people asked me how they should safely shutdown a VSAN cluster. In this post, I will address that question and share my observations. On my three-node VSAN cluster, I had a number of virtual machines as well as a vApp running vCenter Operations Manager VMs. My first step was to shut down all virtual machines in my cluster.
Thanks to our friends at EMC, I was recently given the chance to attend a session on EMC’s new storage acquisition, ScaleIO. This acquisition generated a lot of interest (and perhaps some confusion) as VMware Virtual SAN product seemed to play in that same storage area. My good friend Chad Sakac over at EMC wrote about this some 6 months ago in his evocatively titled blog post VSAN vs. ScaleIO fight! Chad explains where, in his opinion, each product can be positioned and how EMC/VMware customers have a choice of storage options. His article is definitely worth a read. I…
This is something which comes up a lot. In the past, many people used a by-product of the Storage vMotion operation to rename all of the files associated with a virtual machine. In this vSphere 5.1U1 post, I mentioned that we brought back this functionality but you had to set an advanced parameter to make it work. Well, in vSphere 5.5, it works without the advanced option. The following blog post shows you this rename of virtual machine files using Storage vMotion in vSphere 5.5 to rename all of the files associated with a virtual machine.
I wrote about this issue on the vSphere blog some time back. Essentially, the issue described in that post was if a VM that was being replicated via vSphere Replication was migrated to another datastore, it triggered a full resync because the persistent state files (psf) which tracks the changes were deleted. All of the disks contents are then reread and check-summed on each side. This can have a significant impact on vSphere Replication’s RPO (Recovery Point Objective).
Continuing on the series of vSphere 5.5 Storage Enhancements, we now come to a feature that is close to many people’s hearts. The vSphere Storage API for Array Integration (VAAI) UNMAP primitive reclaims dead or stranded space on a thinly provisioned VMFS volume, something that we could not do before this primitive came into existence. However, it has a long and somewhat checkered history. Let me share the timeline with you before I get into what improvements we made in vSphere 5.5.
A number of new enhancements around Microsoft Clustering Services (MSCS) have been introduced in vSphere 5.5. I wanted to cover those in this post as I know many of you continue to use MSCS for service availability in your vSphere environments.