In terms of OBAS "DNS Hosting" means that a domain DNS zone is kept on OBAS name servers. In this case the domain is shown in Domain Manager (Top > Service Director > Domain Manager > Domains) and has "DNS Hosting" enabled:

Domains' DNS zones exist on the OBAS-managed name servers as .zone files in named directory:

[root@ns1 ~]# grep directory /etc/named.conf
        directory       "/var/named";
[root@ns1 ~]# ls -l /var/named/*.zone
-rw-r--r-- 1 named named 526 Oct 16 06:01 /var/named/
-rw-r--r-- 1 named named 526 Oct 16 06:33 /var/named/
-rw-r--r-- 1 named named 526 Oct 16 06:29 /var/named/

If "DNS Hosting" is enabled for a domain but the domain's DNS zone is missing on the name servers, please refer to KB articles below for troubleshooting:

How does DNS management work in OBAS?

DNS zones are not synced to OBAS-managed nameservers

[Troubleshooting] Domain is not resolved

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