Filesystem overlay ?

[William Park]

I would appreciate if someone with better memory can kick me in the
right direction... 

Suppose you have read-only filesystem (eg. CD-ROM) mounted on /var.  Is
there some overlay feature that you can enable (in kernel or
filesystem), so that /var appears to be read-write while the system is
on.  But, when you reboot, you're back to original /var content.

I've remember something like this is possible in 2.6.  But, name or
keyword escapes me.

-- 
William Park <opengeometry-FFYn/CNdgSA at public.gmane.org>, Toronto, Canada
Slackware Linux -- because I can type.
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