What?
There should be a Show received messages link for each node on the Nodes/Cluster Configuration page, which (when clicked) initiates a search on gl2_source_node:$NODE_ID.
Why?
The need is similar to the Show received messages option available per input on the Inputs page (/system/inputs): sometimes you want to quickly see the log messages coming in (or not coming in) through a certain path.
Having a way to directly jump from the Nodes/Cluster Configuration page to a search matching a particular node would make investigating potential node issues just a bit easier.
Your Environment