changing massively to dns zones

I would to decrease TTl in all my zones and i do it with a simple update sql, then i with another update i change the serial on all the zones setting it to today+prog; finally i would force ispconfig to flush all these changes onto zone files.
I dunno I can do it, I could do it using sed, dirty and quickly, like this:

Code:

for i in `ls -1 pri.*`;
do
        sed -i -e "s/$(date +%Y)....../$(date +%Y%m%d)$1/g" $i ;
done

I would let ispconfig do it, it's better
I have tried with tools/resync, but it didn't the trick.

is there a way to force a flush?

 

resync does it, but as vm is small, it does slowly
it's enough to wait