12 Oct
2007
12 Oct
'07
1 p.m.
Jules Richardson wrote:
I suppose real computers have a separate service
processor for this kind
of thing, so it's easy to put things right even if something does go
wrong (plus of course the update can *only* be done from the service
processor - not from some rogue code running on the main CPU)
One would think so, yes?
Pat Finnegan helped me revive an IBM 43P-260 awhile back - arguably
workstation-class, but well into my idea of "a real computer". It had a
version mismatch between the service processor's firmware and the main
system firmware, probably due to a hosed firmware update. This
completely bricks the system - no boot, no recovery option, nada. you
can talk to the service processor, but the SP's firmware flash option
requires that the system boot. Catch 22.
IBM's supported repair option was to replace the entire I/O planar,
where the service processor's EEPROM lives. The I/O board is about 2/3
of the system's logic, with the "system board" being basically a CPU/RAM
backplane.
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