I haven't noticed this, but if that was the case, you could use a file manager (such as Adobe Bridge) to batch modify all uppercase extensions to lowercase, right?
I suppose, but I'd like to resolve the issue.
I don't believe the issue lies with the destination share,
Actually I do. What seems to happen is that when the file name is short enough, it will end up being one case, when it's longer, in the other. The reason behind this certainly being how some file systems discriminate between long file names and short ones, and not adding a long name, if the file can be described with teh short name (or simply using the same name). Depending on which part your other system reads, this may show up as different case names. Likewise, you could simply be seeing code page/ Unicode conversion issues during network transfers. If only one workstation has a different setting than the others, it might royally interfere with the file naming on the storage, beause then the files will use the name defined by the workstation who requested/ created it (first come, first served). Anyway, this is far too high-endish and specialized stuff you are working with, so I don't think your will get conclusive answers here. I even couldn't find out what CIFS actually does use under the hood, as I strongly believe it's just a wrapper system for another native file system (anything from FAT16 to Linux EXT), so maybe ask the Deadline people and Isilon...
Interesting take, however:
The errors occur inconsistently within a batch with the same length of filenames, and also with specific render machines. For example, we might have jobs named:
V3_HD_MC_60001 throuh V3_HD_MC_60020
where 3 or 4 of those have .MOV extensions and the rest have .mov.
An individual render machine will write one file with .MOV, and the next as .mov.
CIFS on Isilon is using Samba on a FreeBSD-based OS. Their support has had me edit the smbd.xml conf file, without success. And we should be seeing errors with the Etymonix .avi files as well, if the share were the issue, but we're not.
Deadline reports writing all of these files as lower case...
There are so many factors here, I figured I would take a shot in the dark.
Have you checked/ monitored your network? Maybe, when being routed differently, some of the names end up being different. so in essence, the routers/ switches introduce some sort of name conversion by modifying the packages. Just an idea...
I have not. I will try a packet capture on one of the nodes when it's in the middle of rendering the wrong extension, and go from there.