I've started sending Palo Alto logs to Graylog, and a stream rule picks them out by matching "Palo Alto" in a "tags" field (which is how all my stream rules are; a front-end Logstash instance does the tagging before shipping to Graylog).
I know the Graylog nodes are receiving these events on the network interfaces:
And the stream shows that it is getting events (note the "22 messages/second"):
Yet when I click into the Stream (or search --> tags:"Palo Alto") there are no events to be found.
The only common issue I've seen online is to with timezone settings putting these events into the future, but the time on our Palo Alto Panorama sender is correct (PST) and trying an absolute time search a day into the future reveals nothing.
Version info:
Graylog 2.2.2+691b4b7, codename Stiegl
Elasticsearch 2.4.4
Lucene 5.5.2
I've also got this question unanswered about the search feature not working properly to find events that actually are arriving okay. I doubt it has any relation but for sake of completeness I'll include that here.