After running rsync, I discovered that a file - libdeb.so - that exists in the source tree had been deleted in the target tree. The specific command was....
rsync -aivc \
/mnt/oradb10-bkp20 is an NFS file system mounted ReadOnly and /d00 is a local file system.
I have verified that libdeb.so exists in the source tree and I have no evidence that it was every deleted. (The source tree was created using rsync.)
After discovering that libdeb.so was missing, I reran the rsync command which copied libdeb.so into the correct location.
I did not notice any error messages while rsync was running. The only unusual situation was that the /tmp file system had no free space after the original rsync execution but I cleaned up the /tmp file system before the last rsync execution.
Is it possible that running out of space on /tmp could have caused the error? If so, my preference would be for rsync to fail and report the error.
I meant to include this information in the original post.
[oracle@rh5-appsrvr99 oracle > cat /etc/redhat-release
Red Hat Enterprise Linux Server release 5.7 (Tikanga)
[oracle@rh5-appsrvr99 oracle > rpm -qa | grep rsync
[oracle@rh5-appsrvr99 oracle > uname -a
Linux rh5-appsrvr99.mid.org 2.6.18-308.16.1.el5 #1 SMP Tue Sep 18 07:21:07 EDT 2012 x86_64 x86_64 x86_64 GNU/Linux
Sadly, there's not enough info here for me try to diagnose what happened to you, since what you describe is not how rsync works.