@petermc Hello again.
Yes this is a funny one as it’s cause has yet to be established and I’ve seen it myself: though only very rarely. Since it’s come up again I’ve created an issue so it doesn’t get forgotten:
As for a work around I have just done the following that hopefully mimics the build processes creation of this file from it’s template file: /opt/rockstor/conf/nginx.conf.in
cat /opt/rockstor/conf/nginx.conf.in | sed -e 's/\${buildout:directory}/\/opt\/rockstor/g' -e 's/\${init-gunicorn:bind}/127.0.0.1/g' -e 's/\${init-gunicorn:port}/8000/g' > /opt/rockstor/etc/nginx/nginx.conf
The above command does 3 stream edits (using sed) that in turn replace placeholders for their production values. The command must be run as root on your Rockstor instance so if you don’t trust it don’t run it.
Once the new file is in place (/opt/rockstor/etc/nginx/nginx.conf) you will need to restart your Rockstor service via:
systemctl restart rockstor
or just restart your Rockstor machine.
See how that goes and let us know if it gets you up and running again.
Hope that helps.
EDIT: Sorry forgot to advise the following on the resulting file to remove group and other read access.
chmod 600 /opt/rockstor/etc/nginx/nginx.conf