Intel SE8500HW4 - Manual (Page 92)

System BIOS Intel® Server Board Set SE8500HW4
Revision 1.0
Intel order number D22893-001
80
10.5 IPMI Serial/Modem Interface
The BMC controls whether the COM2 internal connector is electrically connected to the BMC or
the standard serial port of the SIO. Refer to the IPMI 2.0 Specification for more information, with
Intel
® Server Board Set SE8500HW4-specific implementation described in this section.
10.5.1 Channel Access Modes
The BIOS supports the four different channel access modes described in the IPMI 2.0
Specification.
10.5.2 Interaction with BIOS Console Redirection
The BIOS console redirection uses VT-UTF8 console redirection support. This implementation
was chosen to meet the functional requirements. The requirements are set forth in the Microsoft
Windows 2003 WHQL requirements for headless operation of servers. It was also chosen to
maintain a necessary degree of backward compatibility with existing Intel server BIOS products.
The server BIOS has a console that is intended to interact with a display and keyboard
combination. The BIOS instantiates sources and sinks of input/output data in the form of BIOS
Setup screens, Boot Manager Screens, Power On Self Test (POST) informational messages
and hotkey/escape sequence action requests.
Output is displayed locally at the computer on video display devices, currently limited to VGA
displays in text or graphics mode. Input locally may come from a USB keyboard, without mouse
support.
The use of serial port console redirection allows a single serial cable to be drawn in for each
server system, and then the serial cables from a number of servers can be connected to a serial
concentrator or to a switch which will allow access to each server system individually. The
system administrator can switch from one server to another to manage large numbers of
servers without having to physically interact with the individual servers.
10.5.3 Serial Over LAN
The BIOS will automatically start console redirection on COM2 if it detects SOL is enabled in the
BMC. BIOS will set COM2 flow control and baud rate from BMC’s IPMI Serial/Modem
configuration. Data bits will be set to 8 bits/character, no parity and 1 stop bit as per IPMI
messaging requirement. And the console type will be set to VT100+.
The BIOS console redirection on COM2 supports an extra control escape sequence to force the
COM2 port to the BMC. After this command is sent, the COM2 port attaches to the BMC
channel access serial port and the SIO COM2 data is ignored. This feature allows a remote user
to monitor the status of POST using the standard BIOS console redirection features and then
takes control of the system reset or power using the channel mode features. If an error occurs
during POST, a watchdog time-out feature in the BMC automatically takes control of the COM2
port.