Currently, the log analyzer in Confluence scans only atlassian-confluence.log, and does not examine the contents of atlassian-confluence.log.1, atlassian-confluence.log.2, etc.
In cases where the log fills up quickly with errors, crucial error messages may be pushed to later, numbered log files. For example, atlassian-confluence.log might contain logs from the past 4 hours, while atlassian-confluence.log.1 contains a defining error that happened 5 hours ago. Log scanner will not pick up this error, and the user will have to find it manually or diagnose the issue through other troubleshooting methods.
If atlassian-confluence.log contains only recent logs, scan more log files. For example, if the earliest log in atlassian-confluence.log is only from 4 hours ago, continue scanning more logs until you hit a log that is X days old.