It's a Centos 7 VM (kvm) and the download directory is an nfs mount. I use the installer from the nzbget site. I pointed the sabnzbd install to the same directory for downloading.
Here are the nfs options:
(rw,relatime,vers=4.0,rsize=32768,wsize=32768,namlen=255,hard,proto=tcp,port=0,timeo=14,retrans=2,sec=sys,local_lock=none)
Here is my config with server info and passwords removed:
https://pastebin.com/kxCxsALy