Multi-Server Health Check over SSH Pro

Once you look after more than a handful of servers, the problem is not a lack of monitoring. It is that nothing shows the whole fleet on one screen before a change window or after a provider incident. This multi-server health check logs in to every server in a plain text list over SSH, runs the same short probe on each one in parallel, and prints one graded line per server. It needs no agent, no open ports beyond SSH and no database.

We run it by hand around maintenance, from cron with Slack alerts, and with --json to feed a dashboard.