The following describes how to connect your Synology NAS to your ESXi host using NFS :
First make sure NFS is enabled :
NFS has to be enabled ofcourse
Then create an shared folder (or use an existing one)
Add NFS rights, specify the host (ESXi server) and read/write access :
Now goto your ESXi server, configuration –> storage :
Now Add Storage..
Choose Network File System :
Specify you folder (go back 4 screenshots for the information you specified)
Click next and you have an extra NFS datastore!