To Stretch or not to Stretch.....

[LFC]

I am doing a design for a customer for customer who is deploying 10 vSAN environments. The first 8 are standard 'single DC' vSAN's which I have quite a bit of experience of building.

9th Site

The 9th site consists of two computer rooms approximately 500meters apart, connected by 10Gb Fibre.

As I see it I have two options:

• 1 - Deploy a standard Hybrid vSAN with two fault domains - one in each computer room (each containing 2 or 3 hosts (TBC)).
• 2 - Create a vSAN 6.6 Stretched Cluster with a remote witness

The DC's have sub2ms latency between them, and each have their own internet feed. For simplicity I'm thinking of going for option 1, but can anyone offer any other input?

10th Site is identical to 9th Site, but 'All Flash'

Thanks in advance

[Dave Morera]

LFC,

The minimum number of FDs for FTT1 is 3. If you wanted to have only 2 FD, then that implies that FTT=0, which I don't believe you want to do. The FD requirement is based on FTT, the formula is Fault Domain = 2 * FTT(number) +1.

Based on this, option 1 would require another FD or remote witness in order to support FTT=1; in which case it will be the same as option 2.

In this case I would recommend option 2 for simplicity purposes as Stretched Cluster will make it easier to configure certain things like local failure protection, affinity, etc.

Hope this helps.