[KLUG Members] Re: Runing Out of Re:'s on Samba reprocess config file question

[Bryan J. Smith]

On Sat, 2002-03-09 at 17:40, Bob Kanaley wrote:
> I am supposed to be leading the migration from Lotus 123 to integration into
> our M$ based accounting package that has manufacturing modules. It is
> running on NT 4.0 sp6+ with a betrieve database engine, but for our
> production app it looks like we have to move everything to M$ SQL server and
> re-write the entire app so it works with the accounting and manufacturing
> modules (Oh, Joy!!! ).

It still amazes me how much companies still stick with faulty M$
solutions, especially when they are in-house/custom developments.  Every
vertical app/db developer I've spoken to who has tried both VB and
Delphi chooses Delphi.  Now that Kylix is on Linux and has full
PostgreSQL support, I see no brighter path.

> Unfortunatley, I don't know what funny locking is. Smbstatus was my first
> approach to figure out what was going on, but I have trouble understanding
> what the various combinations of DenyMode, R/W and Oplock mean for the
> various smb clients, so I pretty much gave that up.
> For example, I have seen EXCLUSIVE+BATCH Oplocks on DENY_NONE RDONLY files
> while another file will have Oplock NONE on DENY_ALL RDWR. This makes no
> sense to me.

Actually, I have a client running an older DOS-based accounting
packages.  You must _disable_ oplocks under Windows, otherwise
corruptions result.  You can do that _very_easily_ under Samba, and on a
per-share basis, but under native Windows, it is a registry hack that is
unsupported and disabled oplocks on _all_ shares.

Even better yet, a simple solution to the program is to run multiple
instances of DOSEmu from one system where the accounting app is
located.  Works great and replaces their current and costly Multi-user
DOS with extra serial cabling.

> Is it up to Samba to decide the type of Oplock or does the app ask
> Samba for a specific type of Oplock? I have read most of the man
> pages, docs and online books I can find about Samba, but I just
> don't get it.
> No, I didn't see any process no loger exists, messages, but I have
> seen some really bizare entries where an SMBopenX fails and the next
> transaction opens the file that doesn't exist (and then starts to
> write to it)!!!
> For example I logged this last summer when several people were having samba
> access problems.

I have found most issues are issues with the application itself.  One
that native Windows servers happily create corrupt files blindly
(whereas Samba prevents that from happening).

Samba 2.2 with Linux 2.4 (or Irix) seem to handle oplocks best since
they are done at the kernel level.  Especially when you have NFS shares
or local processes accessing the same file.

-- Bryan
   Contributing Author, "Samba Unleashed"


-- 
  "I'm not unemployed, I'm a consultant" -- Dogbert
-----------------------------------------------------
Bryan J. Smith, Engineer    mailto:b.j.smith@ieee.org
SmithConcepts, Inc.      http://www.SmithConcepts.com
      Consulting Engineers and IT Professionals