The advent of VMware virtual machines have taken the level of computing technology to a whole new level. The set of files presented in the virtual mode make things fast and seamless in terms of configuration, storage and implementation. That is the reason why in order to understand VMware virtual machines in a better way it is essential to get an insight of the basic file settings and the formats in which they are executed in the system.
There are basically two formats in which the set of files are saved. One being VMFS (virtual machine file system) and the other being RDM (raw device mapping). It is a fact that both of these formats help you to access VMDK (virtual machine’s desk), but it’s the comparison of RDM vs VMFS in VMware that we are going to emphasize upon down here.
There are several features on the grounds of which we can draw comparison between VMFS and RDM including storage. Here, we also try to understand why VMFS is recommended by VMware for the majority of virtual machines.
When we shift our focus to the VMware studies, then we would find that there is not much performance difference between VMFS and RDM formats. The studies established on the basis of different performance tests reveals the fact that both VMFS and RDM delivers similar I/O throughput for the maximum workloads tested. So what are the features where the difference lies? Let us find out!
RDM vs VMFS in VMware
With the conclusion of the above table, it is quite evident that apart from the deliverance of performance there are certain features on the basis of which we can differentiate RDM vs VMFS in VMware. The performance difference observed between the two formats in negligible, but when we take into consideration the disk data, the assigned role as well as the storage capacity then the variation can be highlighted in an easier way.
As far as the recommendation is concerned, then it is pretty clear that VMFS is advised by VMware for the maximum number of virtual machines. The features and utilities are conducive enough for a long run and that is something that matters a lot. But that does not mean RDM format is out of the equation. It is suggestive in few special situations. One such example is SAN-aware virtual machine.
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