Apology in advance, this is almost stupid question. I have 3 graylog servers in cluster. All are installed on physical RedHat linux 8 systems . All are version 5.0…x. If I go in Graylog GUI to nodes tab, all 3 nodes are shown.
But then I upgraded just node3 to 5.1. Now just nodes 1 and 2 see eachother in their GUI. node3 only sees itself.
I know the probable solution is to upgrade all 3 nodes and all will be fine. Is it true ?
What does your mongodb setup look like? Is it a single server? does it live on any of the 3 servers that also run graylog?
Can you share your server config for each node? You can use something like https://pastebin.com/ to paste longer blocks of text. Be sure to remove password_secret and root_password_sha2 lines.
Also do you see any errors in the graylog server.log (in the log directory on the server for graylog)?
I managed to downgrade node3 to 5.0 version, but part of original problem still persist. also Load Balancer reporting errors and notr showing menus as soon as node3 graylog process comes up.
So there is some kind of problem on node3, but maybe not connected with higher verison 5.1 compared to 5.0.
