Is it 30 minutes from the last change? I made change in master and the changes were applied in my hosts one by one, not together. There was difference of few minutes. So I assume Puppet hosts pull every 30 minutes after they pulled last time?
Yes, that's the default configuration for the puppet agent in daemon mode.
But you can change the update period in file/etc/puppet/puppet.conf
runinterval=xxx
or you can run the agent one time with puppet agent --onetime and use cron to have agent runs synchronized, so you can have catalog changes applied at 02:00 AM