irc.buk.lt has no CNAME records.
Question and response
Question
dig irc.buk.lt. NS
Answer
The response has no answer records.
Authority
buk.lt. 278 SOA ns.emu.lt. hostmaster.emu.lt. 2017060103 10800 3600 604800 300
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0