how do I tell Aix about bad blocks?

[John Scott McCauley Jr.]

Setup: RS/6000, AIX 3.1, and two Wren external scsi drives (ST47467N aka
	Wren Runner II I think)

Problem: bad blocks: 
	system hangs frequently (read errors on paging?)
	errpt gives many 'DISK ERRORS'
	rdump complains of blocks it can't read


Other symptoms:
	certify from concurrent diag: fails 10% though the disk complaining
		of too many unrecoverable errors.
	certify from diskettes: succeeds; no errors at all detected!
	format: fails immediately; complains of hardware error.

I suspect that somehow AIX wasn't told of the defect list. I also
have heard that diag can't format non-ibm hard disks. I could format
the disks on a Sparcstation, but then how does AIX find the defect list?

	Any pointers welcome,

		Scott