vSAN 6.6 adds a major new capability that will deliver a highly-available stretched cluster that addresses the highest resiliency requirements of data centers. The new release will be allowing for storage redundancy within a site AND across sites at the same time.
With this, if a site fails then on the surviving site the data remains highly-available with host and disk group protection. And everything still with simplicity and flexibility, including simple control through policy-based management, per-VM granularity and the ability to enable/disable non-disruptively.
Synchronous I/O occurs within a site, as well as across sites. This means, if a host or fault domain fails in a site, failover will occur in the same site without any loss of data. If a site fails, failover to the other site occurs without any loss of data. Site availability is maintained by the witness VM that resides in a central location, accessible by both sites. Internal availability is maintained by internal witness components.
For a better understanding of the storage policies this offers to you, and the resulting amount of space, required when using these features, I’m adding a great quick reference from Jase McCarty.
Source: Blog post from Jase McCarty
- Blog post “What’s new with VMware vSAN 6.6
- SAP on VMware vSphere
- SAP HANA on VMware vSphere
- SAP on VMware vSAN