Configuring VM Settings 

 

Required Settings

 
After installing the OVF to create the SoftNAS™ Virtual Storage Appliance VM, configure the VM Settings in accordance with the System Requirements recommendations.  The boot disk (hard disk 1) should be set to 30 GB, thin-provisioned.
 
If you aren't sure where to start out with resource assignments, use 4 vCPUs and 4 GB to 8 GB of RAM, then configure your storage and do some benchmarking and observe resource utilization in the SoftNAS StorageCenter Dashboard charts and vSphere performance charts.
 
RAM Note:  The operating system and SoftNAS consume up to 1 GB of RAM, using most of the remaining RAM for cache memory and metadata.  The more RAM you assign the VM, the better your read cache performance will be, as SoftNAS will keep as much data in RAM cache as possible.  If you are planning to use deduplication, then you will need to allocate additional RAM - at least 1 GB of RAM per terabyte of deduplicated storage, to keep the deduplication tables in memory (or supplement the RAM cache with a read cache device).
 
 

Other VM settings

 
The following VM settings are optional:
 
Paravirtual SCSI Disk Controller Support - for maximum throughput and IOPS on VMware, be sure to choose the Paravirtual SCSI Controller for the SoftNAS VM (instead of using the default LSI Logic Parallel SCSI controller).
 
 
VM Snapshot Mode
 
Before applying software updates to SoftNAS after it is in production, and to support online backups in popular backup programs, VM snapshots are useful as part of the backup and recovery process.  Depending on how you plan to manage backups of your VM data, you will need to choose which mode snapshots will operate in.
 
  • Independent Mode - to enable smaller VM snapshots it is recommended to configure the boot disk, Hard Disk 1, in the "Independent" mode.  This causes VM snapshots to apply only to this first hard disk by default (and not include all added data disks, which could be prohibitively large).  The advantage of using Independent mode is VM snapshots will be faster and smaller.
 
  • Dependent Mode - by default, VM snapshots include all hard disks attached to the VM.  When used with SoftNAS and a VM backup process, this setting causes all SoftNAS VM disks to be backed up together as a set.  This results in much larger backup sets, but may be preferable as a means of achieving additional protection and recoverability in the event of a disaster or need to restore the entire storage system to a different computer or location. If you only have a few terabytes to back up, this may be the prudent choice.
 
 
Network Adapter
 
On a typical 1 gigabit network, the default E1000 network adapter is sufficient; however, if you are planning to use a 10 gigabit or higher-performance network card, the VMXNET 3 network adapter should be used for best results and higher throughput.  Note that installation of the VMXNET 3 requires installation of the proper VMware Tools in the guest operating system (in this case, CentOS 64-bit Linux).
 
 
Memory / CPU Hot plug
 
It is recommended to allow CPU Hot Plug and disable Memory Hot Add, which will make it more convenient to add CPU later should you choose to use a lot of data compression or other features that consume additional CPU.  Linux seems to do fine when additional CPU are added at run-time.
 
Adding memory to a running storage server is not recommended (so it's best to add memory with the system powered down and disable hot add of memory at run time).