This article is from a FAQ concerning SCO operating systems. While some of the information may be applicable to any OS, or any Unix or Linux OS, it may be specific to SCO Xenix, Open There is lots of Linux, Mac OS X and general Unix info elsewhere on this site: Search this site is the best way to find anything.
This article is about older Unix systems, long before LVM.
First, do you really need to do this? You might be able to just move a large directory to another filesystem and use a symbolic link instead: see /Unixart/morespace.html for details on that (NOTE- many system directories CANNOT be moved and symlinked!).
If you still feel you need to do it, the best way is to use one of the Super Tar products: you'd wipe out your existing setup, create a larger root filesystem, and restore.
If you have free space on your drive that immediately follows the fs that needs to be larger, you might be able to use John Dubois' ftp://ftp.armory.com/pub/admin/chfssize program.
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