For several months now, my automated nightly incremental backups to an NSF-mounted remote device have been failing. After many false leads, I finally traced the problem to the program automount in /usr/sbin.
This program causes the remote disk to disappear when you log out, and things like remote backups at 2am will then fail. They even fail if you are logged in but the screensaver comes on. This unfortunately is (now) the default behavior, and automount, without asking or warning you, hijacks your NFS mounting point, moves it to its own directory, and creates an alias. I wonder if Bill Gates wrote this? Anyway, you can turn it off by editing the file /etc/hostconfig and changing the line AUTOMOUNT=-YES- to AUTOMOUNT=-NO-.
This will take effect after a restart. If you currently have NFS devices that have been automouted, you will have to unmount them by hand, delete the alii created by automount, remake the corresponding directories for the local mount points and then remount.
This can all be done in NSF manager except for the last step, which now fails with a cryptic "system error 255". You can get around this by mounting with the root command mount -a.
Now my backups work at 2 am like they are supposed to.
[Editor's note: I have not tested this hint...]
Mac OS X Hints
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