Here are my openvas notes. Not sure if it will help. Did you run the setup and make the cert first? Not sure if it matters or not...
Notes:
* openvas-setup (this will setup openvas and run openvas-mkcert and add user)
* openvas-nvt-sync (optionally - if you have internet connection, download latest plugins)
* openvasd -D (run OpenVAS server, ignore the missing inc files warning, we're still building free replacements)
* OpenVAS-Client (run OpenVAS Client)



