vSphere Storage - ESXi 5.1 - Documentation - VMware

vSphere Storage
The device parameter is the path to the head extent device on which VMFS5 was deployed. Use the
following format:
/vmfs/devices/disks/disk_ID:P
Understanding NFS Datastores
ESXi can access a designated NFS volume located on a NAS server, mount the volume, and use it for its storage
needs. You can use NFS volumes to store and boot virtual machines in the same way that you use VMFS
datastores.
ESXi supports the following shared storage capabilities on NFS volumes:
n vMotion
n VMware DRS and VMware HA
n ISO images, which are presented as CD-ROMs to virtual machines
n Virtual machine snapshots
When you work with NFS storage, the following considerations apply:
n The maximum size of NFS datastores depends on the support that an NFS server provides. ESXi does not
impose any limits on the NFS datastore size.
n If you use non-ASCII characters to name datastores and virtual machines, make sure that the underlying
NFS server offers internationalization support. If the server does not support international characters, use
only ASCII characters, otherwise unpredictable failures might occur.
NFS Datastores as Repositories for Commonly Used Files
In addition to storing virtual disks on NFS datastores, you can also use NFS as a central repository for ISO
images, virtual machine templates, and so on.
To use NFS as a shared repository, you create a directory on the NFS server and then mount it as a datastore
on all hosts. If you use the datastore for ISO images, you can connect the virtual machine's CD-ROM device to
an ISO file on the datastore and install a guest operating system from the ISO file.
NOTE If the underlying NFS volume, on which the files are stored, is read-only, make sure that the volume is
exported as a read-only share by the NFS server, or configure it as a read-only datastore on the ESXi host.
Otherwise, the host considers the datastore to be read-write and might not be able to open the files.
Using Layer 3 Routed Connections to Access NFS Storage
When you use Layer 3 (L3) routed connections to access NFS storage, consider certain requirements and
restructions.
Ensure that your environment meets the following requirements:
n Use Cisco's Hot Standby Router Protocol (HSRP) in IP Router. If you are using non-Cisco router, be sure
to use Virtual Router Redundancy Protocol (VRRP) instead.
n Use Quality of Service (QoS) to prioritize NFS L3 traffic on networks with limited bandwidths, or on
networks that experience congestion. See your router documentation for details.
n Follow Routed NFS L3 best practices recommended by storage vendor. Contact your storage vendor for
details.
n Disable Network I/O Resource Management (NetIORM).
n If you are planning to use systems with top-of-rack switches or switch-dependent I/O device partitioning,
contact your system vendor for compatibility and support.
158 VMware, Inc.