What is aliyun-guard?

Aliyun Guard is a monitoring and automation tool for servers rented on Alibaba Cloud, known as ECS instances. Its main job is to watch how much public network traffic an account is using on Alibaba's CDT billing plan and automatically shut the server down before that traffic causes extra charges, then start it again once usage resets or drops back under the limit. The tool checks three things on a repeating schedule: the account's total CDT traffic for the month, the current status of each watched instance, and its pre tax bill. Based on those checks it decides whether to keep an instance running, start a stopped one, or stop a running one, following clear threshold rules. Users can also set a daily on and off schedule per instance, with times that can cross midnight and catch up if the service was briefly offline. Control happens through three interfaces. A terminal menu, opened by typing the command aliyun-guard or the shortcut ag, lets you add or edit instances, run test checks, view logs, and manage settings. A web dashboard offers the same controls in a browser, with charts showing traffic history and what action was taken at each check. A Telegram bot can also report status and accept commands like checking now or turning an instance on or off, with confirmation steps required before any real power action. The project supports several Linux distributions and package managers, and it can run under systemd, OpenRC, or fall back to cron if neither is available. It also ships as a Docker image. Extra features include encrypted backups that can be restored or rolled back, optional automatic backup uploads to S3 compatible storage, a watchdog that restarts the service if it stops responding, and a bulk discovery feature that scans an Alibaba Cloud account for existing ECS instances to import. Credentials are stored with restricted file permissions and are not written to logs.