New single-binary Go tool monitors Linux VPS with 5MB RAM usage

vpsmon is a minimalist system monitor designed for Linux VPS environments, where resource efficiency is critical. Its single Go binary consumes approximately 5MB of RAM, making it suitable for small instances or edge cases where heavier tools like Prometheus or Zabbix would be overkill. The trade-off is functionality: vpsmon tracks only core metrics (CPU, memory, disk, network, uptime, and process count) and lacks features like alerting, historical data, or integrations with external systems. For engineers prioritizing simplicity and low overhead, this narrow focus may be an advantage, but those needing deeper observability will find it insufficient.

The tool’s deployment model is streamlined but carries risks. Installation and uninstallation are handled via curl-piped scripts, which reduces manual steps but requires users to trust the remote source. This approach is common in lightweight tools but bypasses package managers and local review of the script’s contents. The web UI, which auto-refreshes every 5 seconds, is protected by a login with configurable credentials, though the default username and password hash are publicly documented. Engineers adopting vpsmon will need to weigh the convenience of this model against the security implications of executing remote scripts and exposing a monitoring interface.

Configuration is managed through environment variables, allowing customization of the listen address, username, and password hash. The defaults are functional but not secure for production use, particularly the hardcoded admin username and placeholder password. The use of bcrypt for password hashing is a positive, though users must generate their own hashes. The tool’s reliance on environment variables makes it easy to integrate into containerized or scripted environments but may complicate more dynamic setups where configuration needs to change frequently. Its lack of persistent storage means all monitoring data is ephemeral, which aligns with its lightweight design but limits its utility for troubleshooting past issues.