• Fundamental idea is to use vSAN along with vSphere to [[https://github.com/cskrushika/javawb/blob/master/docs/_static/vsan-1.jpeg|alt=vSAN]]

vSphere -> Clusters (Contains multiple ESXi hosts) -> Attached vSAN Host -> Manage -> Disk Management -> Disk Groups (networked) -> Disks (SSD or Std)

  • Storage vMotion can be performed for Storage too.

Introduction

  • vSAN is used to store VM disk files
  • Created as policy based storage
  • The local storage is pooled, integrating it to the hypervisor and vCenter for management, storage policies can be created for each of the different VMs to give specific QoS based on applications running inside.
  • It is also a HA clustered available solution
  • It is a scale-out storage system. i.e., horizontal scaling based on storage requirements. No need for dedicated SAN.
  • It offers QoS for data objects stored in the stores
  • It integrates compute infrastructure, servers running vSphere with a new storage layer built-in to the servers. This is called as hypervisor-converged storage or hypervisor-based software defined storage.
  • It is basically aggregating the disk on each of the servers, both traditional spinning disks and flash based storage. (SSD are used as read-write cache too) to be available for policy-based storage.
  • Once the shared vSAN datastore is created storage policies can be assigned at per-VM level.
  • vSAN is already built-in to vSphere. No software or VM needs to be deployed. vSAN just needs to be enabled.

Policy-driven storage

  • Most of enterprises use Classical NAS made of either iSCSI, Fiber channel etc.
  • It might be made of SATA, fiber channel drives, flash memories etc.
  • Downsides: Storage LUN is defined on an array and VM is put on a LUN. Storage has no idea of workloads
  • With vSAN, SSD are added to servers, or PCI-based flash storage in conjunction with the spinning disks. This creates a server-side storage pool. Existing SAN/NAS storage pools can be added as externals. This virtual data plane is built into hypervisors.
  • The Virtual Data plane abstracts and pools heterogeneous storage.
  • De-duplication, replication, encryption can be developed as services over VMware-centric Data Services.

[[https://github.com/cskrushika/javawb/blob/master/docs/_static/vsan-2-policydriven.jpeg|alt=vSAN Policy-driven storage]]

Benefits of using vSAN

  • Reduce storage costs - the extremely expensive NAS/SAN storages can be managed without the administration overhead. Fiber channel storage are cheaper too.
  • Prevents vendor lock-in.
  • Simplify Management
  • Improve Performance - flash layer is used at compute layer to improve performance. Read-writes happen via flash storage.
  • Reduce operational costs - easy to add/remove storages.
  • Improve reliability - All VMs-storage can have HA. Data is spread across all hosts participating in the cluster datastores. Need not worry about hot swaps, RAID levels.
  • vDI-Virtual Desktop Infracture
  • High performance
  • Bottlenecks
  • Tier 2/3 Test & Dev
  • Fast provisioning
  • Low cost
  • Big Data
  • Scale-out
  • High bandwidth
  • DR Target
  • Reduced hardware at remote site
  • Replace expensive SANs and save on costs

Hardware Requirements

  • Any Server on VMware compatibility guide
  • A flash storage device - SAS/SATA/PCIe SSD - at least 1
  • Traditional spinning disk - SAS/NL-SAS/SATA HDD - at least 1
  • 1/10 Gb NIC with dedicated network for vSAN
  • SAS/SATA Controllers (RAID controllers must work in pass through or RAID 0 mode)
  • 4-8 GB USB, SD cards - to boot ESXi.

Others: Minimum of 3 ESXi 5.5 hosts with all contributing local disks (1 SSD and 1 HDD) to VSAN cluster Hosts must be managed by vCenter and configured as a vSAN cluster

Two ways to build a vSAN

1. Build your own Any server on the VMware compatibility list Add flash based storage Combine with existing spinning disks Add the compatible RAID controllers * Build your own Hyper converged infrastructure with vSAN

2. Use vSAN ready nodes Pre configured server with ready to use vSAN They already have necessary hardware built into them. * Configued with vSphere.