Best way to handle multiple zones

[Ryan McCain]

I have 3 zones that need to stay in sync.  For example host1.domain1.com needs to be the same as host1.domain2.com and host1.domain3.com.  What is the best way to handle this? 

I was thinking of writing a script to update the domain2 and domain3 zone files when I update the domain1 zone file but figured there has to be something in built into BIND that handles this as I'm not the only one who does this.

Thanks..