But the resulting is (not from same logrow, but You see the format:
date: 2020-03-25 00:00:00 +02:00 (hovers “correctly” 2020-03-25)
time: 08:34:00.191Z (can leave the Z by altering pipeline regex)
Graylog internally store timestamps as UTC, and show it as timezone you setup (based on user account profile settings). If you login as admin user, check if you have setup correct timezone in server.conf file:
Change line: root_timezone = Europe/Bratislava
or similar to your real timezone, and restart graylog service.
If you use another user (as admin), chcek your timezone settings in your use profile.
I did this with extractors and not pipelines, but I’m sure you can modify… the grok patterns in Graylog weren’t enough, so I created 2 new ones based off existing ones and then used them in my extractor.