I'm at the "we should start to think about logging" phase of a new project, and the recent "How I store server logs in Google Spreadsheets" post (https://news.ycombinator.com/item?id=8317868) has me wondering:<p>How do you manage your server logs?<p>Which libraries or technologies work well? Which don't? Which techniques do you have experience with? What do you like about them? What scales well with multiple machines?<p>How long do you store your logs? Do you use server logs for performance and usability analytics, or do you record that information elsewhere?