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[ih] why did CC happen at all?

On 9/2/2014 9:59 AM, Craig Partridge wrote:
>> So that weak 16 bit UDP checksum can help catch this stuff.  I wonder
>> how many corrupted files were created with NFS and broken ethernet
>> hardware?
> Lots and lots.
> At one point, a late generation of BBN Butterfly computers had a low voltage
> problem on a bus that would cause some bytes of a DMA from network adapters
> to be garbage.  Trashed the NFS filesystem, as I recall, about once a week.

at NCD, ted lemon hacked the CVS (concurrent versioning system; based on
RCS, similar to SCCS) to do an MD5 checksum on any file after merging,
and to repeat the operation if there was a mismatch between the version
on the local (committer's) workstation and the remote (NFS based) file
server it was committing to. this was after the engineering group had
missed more than one deadline due to mysterious 11th hour build failures.

so, yes.