RT-11: ?DIR-F-Invalid directory - test-drb@ccmp.vtda.org

3 Feb 1999

...
 Second to the last command: IND SYSGEN
Last command: told it to build only the monitors 
Then I would say that it may depend on what you specified for the
output files for the sysgen.

You see, it is possible for just about any command issued under RT
to specify a disk without a filename... in which case the output of
whatever command you have issued will be to the *disk*, beginning
with block 0... this means that depending on how many blocks are
written, you may wipe out the boot block (0), home block (1),
secondary boot blocks (2-5), directory (6-67) and files (beginning
with block 68).

...
 It made it through the first bit of assembling (pardon
the description,
I'm still learning) and then it bombed.  I tried to start it again and it
bombed immediatly.  At which point I decided to type: BOOT DU2:  
Again, I'd need to see the *exact* commands issued to know how bad it
might be...

...
 The worst part is that I'd noticed that FLX under
RSX11M couldn't write
to the drive the night before.  I guess I should have backed up my data
at that point. 
Hmmm... then sysgen and what it was doing may not be the problem.  What
is the disk you are using?  If an MSCP disk (like an RD series disk),
one or more blocks may have the 'forced error' bit set... which results
in errors when you attempt to read it.  The way to clear this error is
to write the block (which I believe results in a revectoring process for
the bad block).  The data for that block may be lost, however...

I seem to remember the option '/K' for DUP... I'll have to check the
documentation.

One thing which may be a problem is that if the bad block is in the
'system area', blocks 0-68, then RT pretty much refuses to allow you
to do anything with the disk... the idea being that there are times
when not enough of a device driver is in memory to do bad-block
revectoring...

...
 I guess I should look at it this way, even if I
can't recover the data, I
think I've got printouts of most of it.  I'll only really have to
re-enter a couple of the files, since the rest I don't really need.  
I think it may be time to resurrect my RT volume analyzer and recovery
program and get back to work on it...

...
 Does RT-11 have some sort of utility like
"BRU" under RSX-11, or "BACKUP" 
under VMS?  I think I need to start backing up nightly to TK50 if I'm
going to be doing much work on the system.  
BACKUP.SAV...

KMON (keyboard monitor) command 'BACKUP' (or backup/restore)

					Megan Gentry
					Former RT-11 Developer

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