On Tue, 23 Jan 2007 11:48:42 -0500 "Erick Perez" <eaperezh at gmail.com> wrote: > What documents can I read to make /var and /tmp sit on a ram disk and > boot the operating system in read write and switch to read only after > booting? One approach that you could take is mounting the filesystem read-only, and mounting a tmpfs filesystem as a writable overlay using unionfs. The following paper describes various approaches how you could do this: http://www.am-utils.org/docs/sipek-ols2006/index.html The CentOS live CD also uses unionfs (and squashfs), so it could be useful to look at that as a sample implementation. -- Daniel PS. unionfs is an additional kernel patch, and adding that to the CentOS kernel makes it an unsupported kernel. Though, precompiled kernels with unionfs are available through the Live CD build infrastructure on CentOS mirrors (/centos/4.4/build/livecd).