datastore usage on disk alarm in vsphere 6.0

There is a second reason for creating smaller VMware datastores: the blast radius for an administrative error. Small datastores mean more queues, which means higher potential disk performance. Each datastore has a limited queue, which puts a ceiling on datastore performance. So, why not create the largest datastores you can and pile all your VMs on the lowest number of them? The short answer is queueing. There isn't one single datastore size or VM number per datastore that works for everyone, or even one that works for every datastore in your data center. You rarely encounter cases where a single datastore can't deliver the capacity or performance your VM requires. Keeping the entire VM on one datastore means the VM only depends on that datastore, which simplifies VM management. Once you know your VMs' disk space requirements, you can design your datastore. The provisioned size is always the same as the consumed size. The disk consumes its maximum size from the datastore from its creation, even if it contains no data. If the maximum size for a vSphere virtual disk (62 TB) or datastore (64 TB) creates a problem for your design, then you should review your design, because you might be doing something wrong. When using fully allocated - or thick-provisioned - virtual disks, calculate the required capacity for each VM, and map those VMs to VMware datastores. When designing storage for vSphere, figure out your VM and application requirements first. You might consider using a planning spreadsheet that totals this requirement for every VM you expect to run. Once you know the total size of all of a VM's disks, add its configured memory size and a gigabyte for miscellaneous files to determine its total disk requirements. VMware vSphere 6.0, 6.5 and 6.7 enable virtual disks up to 62 TB, which is sufficient for almost any VM use case. However, for a database server, you usually need multiple virtual disks because each disk has its own queues, which translate to higher potential database performance.

For a large file server, you might use a single large virtual disk to keep all the file share data. Other types of VMs hold more data, which the system places on additional virtual disks. These VMs usually just have the boot virtual disk. Some VMs don't hold any extra data, such as those that house web servers that refer to external databases for their data. On Windows, you only have a single drive letter on each virtual disk. This is because the system adds new space to the end of the disk, so you can only grow the partition into that space. You can increase virtual disk size later, but you can only scale the last OS partition on the disk. Every VM needs a boot disk, which uses tens to hundreds of gigabytes, depending on the OS and applications. Size your VMsįirst, you should design your VMs to accommodate your applications. Still, when you create VMware datastores, you must understand the way scaling can affect performance and plan accordingly. Luckily, most storage vendors offer all-flash arrays or wide striping that significantly reduces the requirements for storage performance design.

If you use Virtual Volumes ( VVOLs), then you might have even fewer storage design tasks to worry about. VMware vSphere 6.0, 6.5 and 6.7 and modern storage systems have removed some of the technical constraints that made accommodating certain workloads difficult.

Datastore usage on disk alarm in vsphere 6.0