vsun 2 hard disks at 3Tb and 1 4Tb

[crazych]

Test vmware vsan 5.5, and there is a problem. I have 2 hard disks at 3Tb and 1 4Tb I'm all set, but for some reason I get the error message

"Cannot complete file creation operation.

The policy requires 3 hosts contributing storage, only found 2 in the cluster.

Failed to create object."

I understand that I cannot use drives of different sizes?

[zdickinson]

Good morning, you should be able to mix drive sizes.  It's not a best practice, but you can do it.  I have two suggestions.  One, either don't enforce the FTT policy or create an FTT = 0.  Delete and wipe a disk group one at a time and then re-create.  Two, check the MTU of all items in the vSAN networking stack.  Thank you, Zach.

[crazych]

If I disable the policy ftt then I have in case of failure of 1 server, the data is unavailable?

[depping]

you shouldn't go FTT=0, this should just work. 1. why aren't you testing VSAN 6.2? (vSphere 6.0 U2) 2. is multicast correctly configured? 3. have you looked at the health check? (I recommend 6.2 as it gives more details around the state of the environment and troubleshooting is much easier as a result)

[zdickinson]

Correct, you would be in danger if you had a failure.  This would only be done in a test environment and then FTT re-enabled after the work had been done.  Thank you, Zach.