Jasemccarty's Posts

'Host Pinning' is a term often used when using the vSAN Host Affinity feature. Stretched Cluster vSAN (since vSAN 6.6) has allowed for 'Site Affinity' to give you the ability to have data only in one site or the other. Consider 2 VM's with a need for one in each site. Say they are using DAG, or some other application replication technology, and you do not want to write to both sites. Essentially, data is only needed in one site for each VM because data is replicated at the application layer. Create a Storage Policy with the following rules (minimum) for the VM to reside in the Preferred Site: PFTT=0 SFTT=1/2/3FTM=Mirroring/Erasure Coding Data Locality: Preferred Fault Domain Here's that policy in the vSphere Web Client: And here's the same policy in the new vSphere Client (HTML5) Create a Storage Policy with the following rules (minimum) for the VM to reside in the Secondary Site: PFTT=0 SFTT=1/2/3 FTM=Mirroring/Erasure Coding Data Locality: Non-Preferred Fault Domain You'll also want to use VM/Host Groups/rules with the "Must Run On..." option to make sure that the VM for the Preferred Site only runs on the Preferred and the other only runs on the Non-Preferred site. Most of this is covered in detail in the vSAN Stretched Cluster Guide: https://vmware.com/go/vsanstretchedclusterguide I hope this helps. Jase

This is covered in v1.4 of the PowerCLI Cookbook for vSAN on page 87 (as updates are published, this page may change). The section is: Useable vSAN Capacity based on Storage Policy PowerCLI 11.2 Added the VsanWhatIfCapacity property was added to the Get-VsanSpaceUsage cmdlet. First you have to grab the policy that you'll use, and then Here's the code from the example in the cookbook: PS /> $DefaultPolicy = Get-SpbmStoragePolicy -Name "vSAN Default Storage Policy" PS /> $RAID5Policy = Get-SpbmStoragePolicy -Name "RAID5" PS /> (Get-VsanSpaceUsage -StoragePolicy $DefaultPolicy).VsanWhatIfCapacity StoragePolicy                TotalWhatIfCapacityGB FreeWhatIfCapacityGB -------------                --------------------- -------------------- vSAN Default Storage Policy             4471.21875     4201.66796873882 PS /> (Get-VsanSpaceUsage -StoragePolicy $RAID5Policy).VsanWhatIfCapacity StoragePolicy TotalWhatIfCapacityGB FreeWhatIfCapacityGB ------------- --------------------- -------------------- RAID5               6706.8298017066     6302.50352873374 Remember that different policies will give you different usable space. The FreeWhatIfCapacityGB is what I think you are looking for.

ecsaw​ Because vSAN and Management both use the same TCP stack, if vmk0 (Management) and vmk1 (WitnessPg) are on the same subnet, you will observe a multi-homing situation (KB 2010877). You could tag only vmk0 for "vSAN Traffic" if you desire, as this is a supported configuration. Keep in mind you will want to isolate/protect that network from non-administrative access. I go into some more detail here: Understanding the vSAN Witness Host - Traffic Tagging - Virtual Blocks