DNS not resolving normailly

I’m on latest beta 30, DNS is working with troubles on the containers

/app # nslookup github.com 8.8.8.8                                                                                                                                                       
Server:    8.8.8.8                                                                                                                                                                       
Address 1: 8.8.8.8     
nslookup: can't resolve 'github.com': Try again   

8.8.8.8 is reachable. Have somebody met?