I think a good log system should give you the ability to store everything but filter quickly. So for example I'll set up my systems to store everything down to

I think a good log system should give you the ability to store everything but filter quickly. So for example I'll set up my systems to store everything down to LOG_DEBUG because I might want that information. But when I'm actually looking at the logs I like being able to exclude the DEBUG messages and look at the general behavior, then drill down when I think I understand what the sequence of events is. Good log systems should support this without making me filter as I'm storing the data. Also in UNIX systems I wish there was a way to generically pipe the output of a command to the system log while preserving the return code in case the command exits. In BASH you can configure the pipe behavior to propagate errors to the calling shell, but in normal shells the last return code is the one that gets stored, which is not usually what you want. It would be really cool if the logger utility captured return codes from upstream and returned them so that I can use it in the antiquated SystemV init scripts I have to maintain.