The DataCore Server Settings
DataCore Servers Running in Virtual Machines
For ESXi 7.x or ESXi 8.x, please refer to the ‘Known Issue’ section.
Please see:
Hyperconverged and Virtual SAN Best Practices Guide
Operating System Type
When registering the host, choose the 'VMware ESXi' menu option.
Port Roles
Ports that are used to serve virtual disks to hosts should only have the front-end role checked. While it is technically possible to check additional roles on a front-end port (i.e., Mirror and Backend), this may cause unexpected results after stopping the SANsymphony software.
When SANsymphony has been stopped, Front-end and default Mirror Ports will also be 'stopped'. Ports with the back-end role or Mirror Ports that are explicitly configured to use only the Initiator SCSI Mode will remain ‘running’.
Multipathing
The Multipathing Support option should be enabled so that Mirrored virtual disks or Dual virtual disks can be served to hosts from all available DataCore FE ports. Also see the Multipathing Support section from the SANsymphony Help.
Non-mirrored Virtual Disks and Multipathing
Non-mirrored virtual disks can still be served to multiple hosts and/or multiple host ports from one or more DataCore Server FE ports if required; in this case the host can use its own multipathing software to manage the multiple host paths to the Single virtual disk as if it was a Mirrored or Dual virtual disk.
ALUA Support
The Asymmetrical Logical Unit Access (ALUA) support option should be enabled if required and if Multipathing Support has also been enabled (see above). Please refer to the Operating system compatibility table to see which combinations of VMware ESXi and SANsymphony support ALUA. More information on Preferred Servers and Preferred Paths used by the ALUA function can be found on in Appendix A.
Serving Virtual Disks
For the first time
DataCore recommends that before serving any virtual disk for the first time to a host, that all DataCore front-end ports on all DataCore Servers are correctly discovered by the host first.
Then, from within the SANsymphony Console, the virtual disk is marked Online, up to date and that the storage sources have a host access status of Read/Write.
To more than one host port
DataCore virtual disks always have their own unique Network Address Authority (NAA) identifier that a host can use to manage the same virtual disk being served to multiple ports on the same host server and the same virtual disk being served to multiple hosts.
While DataCore cannot guarantee that a disk device's NAA is used by a host's operating system to identify a disk device served to it over different paths generally we have found that it is. And while there is sometimes a convention that all paths by the same disk device should always using the same LUN 'number' to guarantee consistency for device identification, this may not be technically true. Always refer to the host Operating System vendor’s own documentation for advice on this.
DataCore's Software does, however always try to create mappings between the host's ports and the DataCore Server's Front-end (FE) ports for a virtual disk using the same LUN number where it can. The software will first find the next available (lowest) LUN 'number' for the host-DataCore FE mapping combination being applied and will then try to apply that same LUN number for all other mappings that are being attempted when the virtual disk is being served. If any host-DataCore FE port combination being requested at that moment is already using that same LUN number (e.g., if a host has other virtual disks served to it from previous) then the software will find the next available LUN number and apply that to those specific host-DataCore FE mappings only.
Path Selection Policies (PSP) and SATP rules
See VMware Path Selection Policies for PSP and SATP-specific settings.
Also see:
Video: Configuring ESXi Hosts in the DataCore Management Console