vsphere-esxi-vcenter-server-55-storage-guide

vSphere StorageThe device parameter is the path to the head extent device on which VMFS5 was deployed. Use thefollowing format:/vmfs/devices/disks/disk_ID:PUnderstanding NFS DatastoresESXi can access a designated NFS volume located on a NAS server, mount the volume, and use it for itsstorage needs. You can use NFS volumes to store and boot virtual machines in the same way that you useVMFS datastores.ESXi supports the following storage capabilities on NFS volumes:• vMotion• VMware DRS and VMware HA• ISO images, which are presented as CD-ROMs to virtual machines• Virtual machine snapshots• Virtual machines with large capacity virtual disks, or disks greater than 2TB.When you work with NFS storage, the following considerations apply:• The maximum size of NFS datastores depends on the support that an NFS server provides. ESXi doesnot impose any limits on the NFS datastore size.• If you use non-ASCII characters to name datastores and virtual machines, make sure that theunderlying NFS server offers internationalization support. If the server does not support internationalcharacters, use only ASCII characters, otherwise unpredictable failures might occur.NFS Datastores as Repositories for Commonly Used FilesIn addition to storing virtual disks on NFS datastores, you can also use NFS as a central repository for ISOimages, 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 datastoreon all hosts. If you use the datastore for ISO images, you can connect the virtual machine's CD-ROM deviceto 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 volumeis 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 StorageWhen you use Layer 3 (L3) routed connections to access NFS storage, consider certain requirements andrestructions.Ensure that your environment meets the following requirements:• Use Cisco's Hot Standby Router Protocol (HSRP) in IP Router. If you are using non-Cisco router, besure to use Virtual Router Redundancy Protocol (VRRP) instead.• Use Quality of Service (QoS) to prioritize NFS L3 traffic on networks with limited bandwidths, or onnetworks that experience congestion. See your router documentation for details.• Follow Routed NFS L3 best practices recommended by storage vendor. Contact your storage vendor fordetails.• Disable Network I/O Resource Management (NetIORM).• If you are planning to use systems with top-of-rack switches or switch-dependent I/O devicepartitioning, contact your system vendor for compatibility and support.138 VMware, Inc.