Troubleshooting

I don't see any hosts

Check that your datadir contains a subdirectory per host and that those subdirectories contain .rrd files generated by Collectd.

Graphs render empty

Ensure rrdtool is installed on the server running collectd-web and that the user has read access to the .rrd files.

Port 8888 already in use

Pass --port to runserver.py or update the systemd unit to use a different port.