SCAP completes but doesn't download data - NVT downloads ok

Hi All, I’ve searched back through the threads and I can’t find this exact issue - although there are lots of reports about failing to get the SCAP and cert data (mostly network issues) they don’t appear to be describing what I am seeing

I’m running GVM from a recent Kali build - Greenbone Vulnerability Manager 20.08.0 - I’m running this within a VirtualBox VM
I’ve never had GVM working on this platform so it could be fat fingers on my part (although the install was largely scripted).

Networking seems to be ok in that I get a response from the Greenbone feed as described below (I also get a full download of NVTs)

I run sudo runuser -u _gvm – greenbone-scapdata-sync

It appears to run and complete with no errors but with no data received

"receiving incremental file list
13 100% 12.70kB/s 0:00:00 (xfr#1, to-chk=0/1)

sent 43 bytes received 114 bytes 104.67 bytes/sec
total size is 13 speedup is 0.08"

But as you can see it is over in a flash with no data downloaded.

If I look in the log file /var/log/gvm/gvmd.log it says it can’t find the SCAP database and will build it from scratch and I don’t see errors to indicate that it hasn’t been able to do so. But I get this same message every time.

“md manage:MESSAGE:2021-01-30 18h07.49 utc:3446: No SCAP database found
md manage:WARNING:2021-01-30 18h07.50 utc:3468: update_scap: No SCAP db present, rebuilding SCAP db from scratch
md manage: INFO:2021-01-30 18h07.50 utc:3472: OSP service has different VT status (version 202101291105) from database (version (null), 0 VTs). Starting update …
md manage: INFO:2021-01-30 18h07.50 utc:3468: update_scap: Updating data from feed
md manage: INFO:2021-01-30 18h07.50 utc:3468: Updating CPEs”

I get the same issue trying to sync certdata. But the nvt sync is successful in pulling back data - I presume that the NVT data is not held in the same database so maybe this is a database issue.

Any hints about where I can look will be gratefully received - I’ve been googling for suggestions until I’ve gone cross-eyed. Sadly I’m not a postresql expert or a GVM expert come to that (let’s face it, I’m not any kind of expert, but I’m hoping you will bear with me)

thanks in advance