[Info-vax] Backup/physical question

[JF Mezei]

FYI:

It appears that bad blocks on diskette in a backup/physical do not
result in the block being filled with 0s.

Also, when the output of backup/physical are sent to a saveset, and then
back to a device, backup knows that blocks in the original were not OK:

$ backup/physical/log dua2.save/save lda1:
%BACKUP-E-BADDATA, error in block 1020 of LDA1: detected during save
%BACKUP-S-CREATED, created LDA1:

However, as with direct device to device, the suspect block is filled
with what appears to be data, it is not all zeroed out.


Neat:

Copyed a diskette from VMS to a .dmg file. FTP file to Mac. Opened it as
a disk. Turns out it was an MS-DOS FAT disk !!!

It did have different geometry.
		FAT	HFS
blocks: 	1440	2880
cylinders:	80	80
sectors/trk	9	18
tracks/cyl	2	2

Initially figured it would be single sided, but the tracks/cyl indicates
2. So I guess there was low density and high density which change the
number of sectors per cyulinder.

BTW, I have now had 2 diskettes that were read without any errors and
the process is far faster.