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JUST TO SAY IT AGAIN, YOU MUST THINK WHILE/BERFORE BEFORE USING THIS TOOL, AND MAKE SURE YOU ARE SYNCING THE RIGHT THINGS.
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and read about it. Also, --dry-run, --list-only, and --itemize-changes are good ways to see what rsync is doing, or to test what it might do.
Rsync as a Backup Tool
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