Openvas 9 greenbone-nvt-rsync always fails

I have built 2 different openvas9 systems, one on Ubuntu 16.04 and another on the latest version of Centos 7 and both fail with rsync errors when performing feed syncs.

receiving incremental file list
rsync: read error: Connection reset by peer (104)
rsync error: error in socket IO (code 10) at io.c(785) [receiver=3.1.2]
rsync: connection unexpectedly closed (46 bytes received so far) [generator]
rsync error: error in rsync protocol data stream (code 12) at io.c(226) [generator=3.1.2]

I am tearing my hair out. There is no issue with firewall.

Does anyone have an idea? Thanks.