why not --omit-dir-times with NFS?

[Albert Lunde]

The rsync documentation says:

"O, --omit-dir-times
This tells rsync to omit directories when it is preserving modification
times (see --times). If NFS is sharing the directories on the receiving
side, it is a good idea to use -O."

What's the underlying issue behind this recommendation?

I've got an existing script I wrote that runs rsync between two isolated
hosts, that I'm adapting to run between the nfs servers for two small
clusters of web nodes. I'd like to understand the pros and cons.

I'd like to preserve directory times for historic reasons, but I could
live with only syncing them up occasionally, and I don't want to cause
serious problems.

-- 
     Albert Lunde  albert-lunde at northwestern.edu
                   atlunde at panix.com  (address for personal mail)