There are several name servers in OSA infrastructure. All name servers are registered as master servers.
Checking SOA record serials for the same zone on different name servers, they do not match:
[root@osscore ~]# dig +short SOA example.com @ns1.provider.com ns2.provider.com. root.email.com. 1490429141 14400 7200 2419200 300 [root@osscore ~]# dig +short SOA example.com @ns2.provider.com ns2.provider.com. root.email.com. 1489156387 14400 7200 2419200 300
The behavior is recognized as a product issue POA-109561: SOA serial differs in master DNS servers for domain
The issue affects only OA 7.0. In contrast with OA 6.0, the DNS serials are no longer stored on OA database side, but generated automatically by DNS update tasks. The tasks can become non-synchronous under high load of DNS changes, and the serials will become mismatched.
Add any additional DNS record to the affected zone, process the DNS update tasks and remove the record. This way the zones will get in sync.