Objective 3.4 - Perform Advanced VMFS/NFS Configurations and Upgrades

To view previous Objective click, HERE

Objective Topics:

Describe VAAI primitives for block devices and NAS
Differentiate VMware file system technologies
Upgrade VMFS3 to VMFS5
Compare functionality of newly created vs. upgraded VMFS5 datastores
Differentiate Physical Mode RDMs and Virtual Mode RDMs
Create a Virtual/Physical Mode RDM
Differentiate NFS 3.x and 4.1 capabilities
Compare and contrast VMFS and NFS datastore properties
Configure Bus Sharing
Configure Multi-writer locking
Connect an NFS 4.1 datastore using Kerberos
Create/Rename/Delete/Unmount VMFS datastores
Mount/Unmount an NFS datastore
Extend/Expand VMFS datastores
Place a VMFS datastore in Maintenance Mode
Select the Preferred Path/Disable a Path to a VMFS datastore
Enable/Disable vStorage API for Array Integration (VAAI)
Given a scenario, determine a proper use case for multiple VMFS/NFS datastores

Describe VAAI primitives for block devices and NAS

Block Primitives VMFS:

Acquire on-disk locks
Upgrade an optimistic lock to an exclusive/physical lock
Unlock a read-only/multiwriter lock
Acquire a heartbeat
Clear a heartbeat
Replay a heartbeat
Reclaim a heartbeat
Acquire on-disk lock with dead owner

VAAI NAS Primitives:

Full File Clone
Fast FIle Clone/Native Snapshot Support
Extended Statistics
Reserve Space

Source: vSphere Storage API White Paper

Upgrade VMFS3 to VMFS5

Since my block storage is already at 5, I can’t upgrade it. But if I could I would go here:

Compare functionality of newly created vs. upgraded VMFS5 datastores

Differentiate Physical Mode RDMs and Virtual Mode RDMs

You can use RDMs in virtual compatibility or physical compatibility modes. Virtual mode specifies full virtualization of the mapped device. Physical mode specifies minimal SCSI virtualization of the mapped device, allowing the greatest flexibility for SAN management software.

In virtual mode, the VMkernel sends only READ and WRITE to the mapped device. The mapped device appears to the guest operating system exactly the same as a virtual disk file in a VMFS volume. The real hardware characteristics are hidden. If you are using a raw disk in virtual mode, you can realize the benefits of VMFS such as advanced file locking for data protection and snapshots for streamlining development processes. Virtual mode is also more portable across storage hardware than physical mode, presenting the same behavior as a virtual disk file.

In physical mode, the VMkernel passes all SCSI commands to the device, with one exception: the REPORT LUNs command is virtualized so that the VMkernel can isolate the LUN to the owning virtual machine. Otherwise, all physical characteristics of the underlying hardware are exposed. Physical mode is useful to run SAN management agents or other SCSI target-based software in the virtual machine. Physical mode also allows virtual-to-physical clustering for cost-effective high availability.

VMFS5 supports greater than 2TB disk size for RDMs in virtual and physical modes. You cannot relocate larger than 2TB RDMs to datastores other than VMFS5.

Source: vSphere 6 Storage Guide