If you want easy to install, maintain and use system for logs, then take a look at VictoriaLogs [1] I'm working on. It is just a single relatively small binary (around 10MB) without external dependencies. It supports both structured and unstructured logs. It provides intuitive query language - LogsQL [2]. It integrates well with good old command-line tools (such as grep, head, jq, wc, sort, etc.) via unix pipes [3].