This is a short note on trying to use VOMA, the vSphere On-disk Metadata Analyzer, on a dump taken from a VMFS-5 volume which was upgraded from VMFS-3. This is not an issue if VOMA is run directly on the volume; it is only an issue if a dump is taken from the volume and then you try to run VOMA on the dump. It may error during phase 1- ‘Checking VMFS header and resource files‘ with an error ‘ERROR: Trying to do IO beyond device Size‘. When a VMFS-3 is upgraded to VMFS-5, a new system file, pb2.sf, is…
One of the long-awaited features introduced with vSphere 5.1 was VOMA (vSphere On-disk Metadata Analyzer). This is essentially a filesystem checker for both the VMFS metadata and the LVM (Logical Volume Manager). Now, if you have an outage either at the host or storage side, you have a mechanism to verify the integrity of your filesystems once everything comes back up. This gives you peace of mind when wondering if everything is ok after the outage. There is a requirement however to have the VMFS volume quiesced when running the VOMA utility. This post will look at some possible reasons…
I get a lot of questions around how the vSphere APIs for Array Integration (VAAI) primitives compare from a protocol perspective. For instance, a common question is to describe the differences between the primitives for NAS storage arrays (NFS protocol) and the primitives for block storage arrays (Fibre Channel, iSCSI, Fibre Channel over Ethernet protocols). It is a valid question because, yes, there are significant differences and the purpose of this blog post is to detail them for you.
I had an interesting question the other day about whether Raw Device Mappings (aka RDMs) still had a reliance on the LUN ID, especially when it comes to the vMotion of Virtual Machines which have RDMs attached. I remember some time back that we introduced a concept called Dynamic Name Resolution for RDMs, which meant that we no longer relied on a consistent HBA number or even the path to identify the RDM, but do we still use the LUN ID in vSphere 5.1?
In this post, I want to call out two important matters related to the vSphere 5.1 release & EMC storage. The first is related to Round Robin Path Policy changes, and the second relates to a VMFS5 volume creation issue.
In this post, I want to highlight a number of storage improvements made in vSphere 5.1 that are going to be leveraged by the next release of vCloud Director.
Welcome to the first in a series of posts related to new storage enhancements in vSphere 5.1. The first of these posts will concentrate on VMFS. There are two major enhancements to VMFS-5 in the vSphere 5.1 release. VMFS File Sharing Limits Increase Prior to vSphere 5.1, the maximum number of ESXi hosts which could share a read-only file on a VMFS filesystem was 8. This was a limiting factor for those products and features which used linked clones. Linked Clones are simply “read/write” snapshots of a “master or parent” desktop image. In particular, it was a limitation for vCloud…