Your dedicated server has lots of logs. Almost every service and program running on a Linux or Unix server has a log file associated with it that includes relevant information about processes, errors and warnings. Sifting through all of those logs can be a pain, especially if you need to review old logs or compare them with newer ones. A tool called logstash may be the answer to your concerns.
logstash allows you to collect all of your logs, parse them, index them, store them and search them. For example, you could use it to find all instances of 404 File Not Found errors in your Apache HTTP Server logs, or you could find InnoDB warnings in your MySQL logs. You can get pretty specific with your searches and avoid a lot of false positives.
Freely available for download and installation, logstash is free and open source software, released under the Apache 2.0 license. You can download the source code or install binaries available in its APT or YUM repositories for Debian, Ubuntu, Red Hat Enterprise Linux, CentOS and Fedora.