Solved: Can not use DNS name to link to my NAS within a local LAN

 I use Ubuntu 20.04 at home within a local network the same as a Synology NAS.

Every goes fine except I can not use DNS name to link to my NAS.

I solved the problem by the following:

Solution:

edit the file /etc/hosts

add a line: 

192.168.0.x  xxx.myds.me

(The above local ip and DNS name should be those of your computer.)