Emergency Management Port (Emp) Interface; Com2 Port Switching; Basic Mode; Terminal Mode - Intel 5000 Series Datasheet

System Management

4.28 Emergency Management Port (EMP) Interface

The EMP interface is the Intel implementation of the IPMI 2.0 IPMI over serial feature. The
primary goal of providing an out-of-band RS232 connection is to give system administrators the
ability to access low-level server management firmware functions by using commonly available
tools. To make it easy to use and to provide high-compatibility with LAN and IPMB protocols,
this protocol design adopts some features of both protocols.
The Intel implementation shares the EMP function with the platform's Serial B interface. The
BMC has control over which agent (BMC or system) has access to Serial B port. Hardware
handshaking, and the the Ring Indicate and Data Carrier Detect signals are supported.
The basic mode of IPMI over serial is supported and is available whether or not DC power is on.
Additional details on the IPMI over serial / modem interface is available in the IPMI 2.0
specification.
4.28.1

COM2 Port Switching

As specified in the IPMI 2.0 specification, if EMP is enabled, then the BMC will watch the serial
traffic when the COM2 port is owned by the system. This is done to respond to in-band port
switching requests. Serial traffic snooping is done in basic mode, although the exact sequences
recognized in the two modes is different.
4.28.2

Basic Mode

Basic mode uses a protocol in which IPMI requests are transmitted over the serial port with
minimum framing, providing a low overhead implementation. Command receipt by the BMC is
acknowledged on a per-packet basis.
Basic mode minimumly supports None (un-authenticated) and Straight Password / Key
authentication types. Callback is supported in basic mode.
4.28.3

Terminal Mode

The BMC supports terminal mode as specified in the IPMI 2.0 specification. Terminal mode
provides a printable ASCII text-based mechanism for delivering IPMI messages to the BMC
over the serial channel or any packet-based interface. Messages can be delivered in two forms:
Via hex-ASCII pair encoded IPMI commands
Via text SYS commands
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Intel® 5000 Series Chipsets Server Board Family Datasheet
Intel order number D38960-004
Revision 1.1