mx-backup.serveriai.lt has no CNAME records.
Question and response
Question
dig mx-backup.serveriai.lt. NS
Answer
The response has no answer records.
Authority
serveriai.lt. 3192 SOA ns1.serveriai.lt. hostmaster.iv.lt. 2003102000 43200 3600 1209600 3600
Additional
. 0 OPT ; payload 1232, xrcode 0, version 0, flags 0