How can you analyze large logs?

Question

Debian

Good evening.
There are many different logs from different servers, routers and all that. Everything is written to one rsyslog server, everything is fine, but if the logs are more than a few hundred meters, then how can they be analyzed, parsed according to criteria or errors? I thought about web solutions that would not depend on the platform, but did not find anything.
I will be glad to any ideas. Thanks

Answer 1

gray log

Answer 2

splunk