anyone can point me to documentation or manual what is right way to update slaves. What I want to is when I change record X on master that slaves also pick that change without me manualy have to  do this.

My configuration is OK as on initial zone transfers slaves got data/zones OK. 

I tried 

knotc reload

knotc flush 

knotc refresh 

and restarting knotc service. 

On all this there was nothing in syslog and slaves are not updating
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