From:	CRDGW2::CRDGW2::MRGATE::"SMTP::CRVAX.SRI.COM::RELAY-INFO-VAX" 15-SEP-1989 18:49
To:	MRGATE::"ARISIA::EVERHART"
Subj:	RE: VMS V5.2 breakage

Message-Id:  <8909152235.AA07752@crdgw1.ge.com>
Received: From ICDC.LLNL.GOV by CRVAX.SRI.COM with TCP; Fri, 15 SEP 89 15:07:31 PDT
Date: Fri, 15 Sep 89 15:07 PDT
From: "Kevin Oberman, LLNL, (415)422-6955" <OBERMAN@icdc.llnl.gov>
Subject: RE: VMS V5.2 breakage
To: INFO-VAX@CRVAX.SRI.COM
X-Vms-To: IN::CRVAX.SRI.COM::INFO-VAX

>There's been some confusing postings on this subject since.  Terry implies
>that it is a problem with how the file system determines whether a user is
>allowed read access, not just a BACKUP problem.  This implies that neither
>COPY nor anything else will work either (on a file that a user is supposed to
>be able to read, Zack).  If true, this is a serious problem with the VMS file
>system, not BACKUP or COPY.  The remark about defragmenters makes me wonder
>though; does it only happen because a defragmenter has touched the file?
>If so, then it may not be a VMS problem; perhaps the defragmenter is making
>assumptions about how the file system works that are no longer valid in
>VMS V5.2.  Two that I know of had to be fixed to work with VMS V5.2.  If one
>is running a defragmenter I'd be wary of running it on a new release of VMS
>without testing it thoroughly.
>
>Can we get a clarification on this?  I checked on DSIN and couldn't find
>any articles on it...

OK. Here's the best available information (passed from a friend who get to look
at a DEC Notes conference).

DEC is aware of the problem. It is with the file system but only shows up when
programs try to use retrieval pointers to directly access file segments. BACKUP
does this. COPY does not. For this reason the problem doen't show up often. It
may show up with some user applications, but it's pretty unlikely.

The problem only shows up on an unpriv. operation that is via ACL, Group, or
World access rights. If you own the file or have SYSPRV or BYPASS or READALL,
you won't have a problem. I have been told that the problem has been seen on
systems that don't use defragmenters. (And, Ive seen the file header dumps from
this system, so I believe it.)

Net response--It's probably not all that bad a problem. Look at your system
operations and try to check on just how bad things are. Look at disk
fragmentation and ACLs on your systems. Since data integrety is not at question
and BACKUPs that fail are clearly evident from the error messages, I don't
think I'll lose too much sleep, myself.

					R. Kevin Oberman
					Lawrence Livermore National Laboratory
					Internet: oberman@icdc.llnl.gov
   					(415) 422-6955

Disclaimer: Don't take this too seriously. I just like to improve my typing
and probably don't really know anything useful about anything.

