IPMI (Intelligent Platform Management Interface)
Definition
IPMI is a standardized specification for out-of-band server management and monitoring. It provides a standardized way to monitor hardware status (temperature, fan speed, voltage) and perform remote management (power on/off, BIOS access, console redirection) independent of the host OS.
IPMI operates via a dedicated network interface (BMC — Baseboard Management Controller) or serial connection, allowing administrators to manage servers even when the host is powered off or unresponsive.
Key Concepts
- BMC (Baseboard Management Controller): Dedicated processor on the server motherboard
- LAN Channel: IPMI over Ethernet (requires network connection)
- Redfish: Modern RESTful API replacing IPMI’s proprietary protocols
- SEL (System Event Log): Hardware event logging (power failures, thermal events)
- KVM over IP: Remote console access (keyboard, video, mouse)
- Power Control: Remote power cycle, graceful shutdown, boot device selection
IPMI vs Redfish
| Feature | IPMI | Redfish |
|---|---|---|
| Protocol | OEM-specific (SMBus, LAN) | RESTful HTTP/HTTPS |
| Security | Weak (default passwords) | Strong (TLS, RBAC) |
| Interface | CLI (ipmitool) | JSON API |
| Adoption | Legacy standard | Modern replacement |