Currently, we don't persist anything in /var/log or /run (where some logs go), so at poweroff we lose all system logs. Obviously, this is really bad for post-mortem debugging; if something fails and the power goes off, it's very hard to reconstruct what happened. However, we might not always want to persist logs to avoid wearing out flash storage, in case storage is very limited, or other reasons.

I think we have a few options for handling this:

• Always persist logs
• Never persist logs (what we do today)
• Persist some logs but not others
• Make log persistence be configurable (what should be the default?)

Related but not exactly the same is that we should setup appropriate log rotation. We should rotate logs even if they're not persist, because a long-running system could still fill up the disk. However, if we persist logs, then log rotation is clearly even more important.