Logging is more than just appending to a file. Logging can be a critical piece of infrastructure that allows reconstructing what happened over disparate systems for security auditing, debugging and error post-mortems. Without it, you're flying blind.
Starting with plain old _error_log()_, we move up the food chain to _syslog_ and examine its capacities and limitations. Next, will be an introduction to one of the better open source PHP logging packages---_MonoLog_. We'll show how it's built into Laravel and how to call it from MySQL.
All this is for naught without some way to sort and filter the thousands of logging messages. We'll demonstrate a modern open-source syslogging package: _Graylog_. We will demonstrate how to search and sort the messages we created in our PHP apps. We'll also look at some of the ways _Graylog_ provides to work around the limitations of _Syslog_ using _Graylog_ *extractors* which are the easiest to use and how to construct easy-to-parse messages in our PHP code.