Delegate subdomain cloudflare to other DNS servers

There are many examples where you may need to have a specific subdomain’s DNS be managed by a different nameserver.

The example we want delegate rbl.malware.expert another Bind DNS server for RBL database queries.

First we need Primary Domain (malware.expert) add new NS Records rbl.malware.expert:

Then we need also A-Record rbl2.malware.expert to point BIND-DNS server IP 5.44.240.62:

BIND rbl.malware.expert Zone

The last part is configuring BIND Server, so we need to add there rbl.malware.expert zone. Here example for that:

; rbl.malware.expert
$TTL  86400
@           IN          SOA     rbl.malware.expert. hostmaster.malware.expert. (
                            2016110511
                            28800   ; Refresh 8 hours
                            7200    ; Retry   2 hours
                            1209600 ; Expire  14 days
                            86400 ) ; Minimum 1 day
                ; sub-domain name servers
                IN          NS      rbl.malware.expert.

                ; sub-domain mail server
                IN          MX      10 smtp.malware.expert.

                             A      5.44.240.62

; Hosts
localhost    600 IN          A      127.0.0.1