Product : DataCore, SSY [SDS]/10.0 PSP12, x86
Feature : SC Configuration, Disaster Recovery, Data Availability
Content Owner:  Herman Rutten
Summary
2+sites = two or more active sites, 0/1 or more tie-breakers
Details
Theoretically up to 64 sites are supported.

SANsymphony does not require a quorum or tie-breaker in stretched cluster configurations, but can be used as an optional component. The Virtual Disk Witness can provide a tie-breaker role if for instance redundant inter site paths are not implemented. The tie-breaker node (server or device) must be other than the two nodes presenting a virtual disk. Access to the Virtual Disk Witness is leading for storage node behavior.

There are 3 ways to configure the stretched cluster without any tie-breakers:
1. Default: in a split-brain scenario both sides stay active allowing upper infrastructure layers (OS/database/application) to make a decision (eg. clustering principles). In any case SANsymphony prevents a merge when there is a risk to data integrity, and the end-user has to make the choice on how to proceed next (which side is true)
2. Select one side to go inaccessible
3. Select both sides to go inaccessible.