Bind and restarts - cacheing DNS data

[Reuben Farrelly]

Hi,

Occasionally after upgrading a kernel or installing a fairly major upgrade
of a package on my system, I have to reboot in order for changes to take
effect (a new kernel being an obvious opportunity).  I understand that in
doing so, obviously BIND has to be shut down and therefore loses all the
cached data that it has learnt about various zones that it has recently
cached.

Is there any way that BIND can write this information out to disk and then
reread it upon restart?  Obviously cached zone data can't be cached for any
length of time (most seems to expire or at least need refreshing fairly
quickly), but it seems pointless to have to lose the entire cache just
because I need to reboot my machine.  If the machine is only down for a few
minutes, wouldn't almost all of this data be valid and usable if it weren't
dumped and could be reread into memory?

I'm using BIND8.21...

Reuben