A way for external groups to define their own extensions without conflicting. The first byte of the command and second byte of the response are a field that identifies the entity defining the messages; these bytes are, in effect, an extension of the NetFN. The external groups are free to define the message outside those bounds. Current defined external groups are:
00h CompactPCI 01h DMTF Pre-OS Working Group ASF Specification All other values are reserved. Basically more group extensions, except that the first three bytes (bytes 0-2) of commands and second three bytes (bytes 1-3) of responses are the IANA enterprise number. The owner of the IANA enterprise number is free to define these values any way
they like. OEMs are free to use these messages any way they like.
CHAPTER 5. IPMI COMMANDS
Every response has a one byte error code that is always the first byte of the message. There are a number of error code. Unfortunately, the error responses returned in a response are not bounded per command; the implementor is free to return pretty much anything it likes as an error response. Some commands define explicit error return code for some situations, but not generally. Table 5.2 shows the error codes in IPMI.
Table 5.2: Error codes
Error 00h 01h-7Eh
mand for LUN Timeout Out of Space
Reservation In- valid
Description No error, command completed normally OEM error codes. Implementors may use these error codes for their own commands if a standard error code does not apply. reserved Command-specific error codes. Some commands have specific errors they return that only apply to that command. These are defined by the command. reserved The command could not complete because command processing resources on the MC are temporarily unavailable. The MC did not support the given NetFN and command.
The given command was not supported on the LUN it was sent to. A timeout occurred while processing the command. There was not enough storage space to perform the given com- mand. This is for commands that require reservations (like SEL and SDR commands). This means the reservation number given was invalid or the reservation was lost. The request data was truncated (it is unknown what this means).