User manual
Table Of Contents
- UTCA-5503
- Contents
- 1 Board Specification
- 2 Applications and Overview
- 3 Mezzanine Module Options
- 4 Operations
- 5 Firmware Upgrades
- 6 Overview of Supported Features and Known Limitations
- A MCH Pin List, Connector 1
- B IPMI/PICMG Command Subset Supported by the MCMC
- C IPMI/PICMG Command Subset Supported by the Carrier Manager
- D IPMI/PICMG Command Subset Supported by the uShM
31 UTCA-5503 User Manual
Chapter 4 Operations
4.6.1 RMCP Module
UTCA-5503 provides access to the uSHM through the IPMI-defined RMCP protocol
(refer to section 12 of the IPMI Specification). This IP-based interface allows external
RMCP-capable System Management Tools (e.g. OpenIPMI or OpenHPI with ipmidi-
rect Plugin) to interact with the MCH.
The uShM’s RMCP interface supports message bridging, therefore it is possible to
communicate with the CM/MCMC as well as FRUs located on the IPMB-0 or IPMB-L
buses through this connection.
4.6.2 Cooling Policy
The UTCA-5503 uShM implements a fixed standard cooling policy to control the fans
in the chassis, using a simple yet effective mechanism based on events and time-
outs.
The uShM constantly monitors all temperature sensors in the shelf as well as the fan
speed sensors of each cooling unit. If there are no active events for a specified time,
the uShM will gradually reduce the speed of all fans down to the minimum speed
level defined for each cooling unit.
Any event reporting that a sensor in the system has crossed one of the upper limits
will gradually increase fan speed until that sensor will deassert the event. After a spe-
cific timeout the uShM will then again begin to gradually reduce fan RPM.
Critical temperature events or events from fan speed sensors (indicating fan failure)
will cause the uShM to immediately set all fans to maximum RPM in order to com-
pensate for any potential issues.