- With 5.3.5 we are getting lots of messages on the console like:
GMT [CIFSAdmin]: oplock break timed out to station CST209 for file \NTCR2\w95apps\APPLICATIONS\SPSS\9\spssprod.inf
We support some 1200 Windows 95 PCs, and at peak times we get several messages per minute for different files and PCs. Does anyone know what this means, should we care about it, and if not, can we turn them off!
Hmmm. We've started printing those out have we? I see...
To understand what they are, you first need an understanding of opportunistic locks (oplocks) generally. The clearest description of them that I've uncovered lies in a Microsoft Systems Journal artical which you will find at:
http://www.microsoft.com/MSJ/0100/win32/win320100.asp
If you're not interested enough to read the whole thing, and most people probably aren't, the sections on level 1 and level 2 oplocks should suffice.
So what's with this message? Very simply, some versions of Windows do not reliably respond to oplock break requests. Windows 95 is especially bad, and on a big network it is not entirely surprising that you are seeing quite a few of these. If it's any comfort, this has almost certainly been happening on your network all along, it's just that we're now bringing it to your attention with a message on the console. Perhaps we should have left you blissfully unaware? :-)
In actuality, the non-responsive oplock break "problem" is rarely serious, although it can leave the server end of a CIFS connection with a dilemna on its hands. You'd have to worry about it more if you were using cooperative flat file database applications like Access, FoxBase, DBase and so forth. For these, it is recommended that you turn oplocks off entirely (they don't add any value when cooperative file sharing is the rule rather than the exception). Judging from the message you quoted above, it looks like you just have a multiple-reader type scenario, so non-responsive oplock break requests shouldn't be that big of a deal.
I'm afraid I don't know of a way to turn those messages off, other than to turn oplocks off, which is a rather drastic solution. Someone else at NetApp may know a way, or if I find out internally here I'll e-mail you privately.
Keith