Symbolic Link Dates
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Why doesn't dirvish preserve symbolic link dates and times? Because POSIX operating systems are limited, imposing a limit on rsync.
Dirvish is based on rsync, which in turn is dependent on the available system calls for the Linux operating system. When setting permissions for a symbolic link, rsync uses the lchown system call. When rsync sets file times for files and directories it uses utime. Unfortunately, there is no lutime system call for setting the time on a symbolic link; if you try to use utime on the link, it will change the time of the pointed-to file instead. There are kernel patches out there that permit something like lutime, but they are not standard and thus not addressed by rsync.
If you want to build a backup appliance, it may be worthwhile to patch the kernel and patch rsync to keep track of symbolic link times.
Keith Lofstrom December 26, 2004