Points to Remember while creating Datastore in ESXi

Few days back Shaikh and I worked on QAESXi Server installation, at that time we used all the default options. ESXi is installed and we are able to create the VM's successfully.

Today we got a Task to create a VM with 1TB space. We failed to create the VM on the above ESXi server as it is not allowing to add a disk with more than 256 GB. 

Shaikh resolved the issue. He explained the issue, it was intresting. Issue is "Datastore created with Block Size of 1MB". If Block size is 1MB we cannot create a disk with more than 256GB. 

Here is the combination of Block size and the Disk Space


Block Size 1MB - 256GB
Block Size 2MB - 512GB
Block Size 4MB - 1024GB
Block Size 8MB - 2048GB  


As we cannot do anything, we moved all the VM's to another Server, removed existing datastore and again added with correct Block Size. Gosh, Horrible!!!