I've integrated our PHP web application using Monolog recently and added support for logging into Graylog. Until very recently I've used the Graylog VM and I've successfully logged all the information sent to it.
We've now started a full-fledged dedicated Graylog server : the server is currently logging syslog info through UDP and again it's working perfectly.
However for various reasons we chose to use an HTTP input for the application I'm working on so I created an HTTP local input in Graylog (for the record, I tried a global one, too). No logs from that application are found, however. No exception is raised in the application, which is what would happen in case of a connection error for instance, plus I'm using the exact same configs than on my VM so I'm fairly certain the problem is not on the application side.
What's even stranger is that Graylog does receive traffic on that input !
You can see on the right, in pale gray, that there is traffic on the input but 0 bytes have been processed - or, well, I'm not quite sure what this means.
So: what does that mean? How can I debug and fix this problem?