Questions: how can I get my availability group to be registered as ag-ewgtest.sql.company.com given that my server thinks of itself as server.company.com.

Setup: my SQL Server 2012 availability group is on multiple subnets, similar to what's described at in this MSDN blog article. When I go into Failover Cluster Manager, it shows that name resolution is not yet available:

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I then right-click "Name: ag-ewgtest" and choose properties. I check off "Publish PTR records" and it shows me that the full name is ag-ewgtest.company.com.

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The problem I have is that I'm only being allowed to update the DNS zone sql.company.com. If I change the DNS name to be ag-ewgtest.sql.company.com then the full name becomes ag-ewgtest.sql.company.com.company.com.

I've tried updating my NIC as:

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But hasn't made a difference. How can I change the subdomain that my availability group tries to register itself in?


The Availability Group Listener name is a Computer Name Object (CNO) in Active Directory, not just a DNS entry:


Its location in AD determines where it gets registered. If you want to create a different one somewhere else, you can create a DNS CNAME (alias) pointing to the real Availability Group Listener name:


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  • this implies there is no way to change the subdomain that my availability group tries to register itself in and that I need a manual workaround. Is this correct? – Elijah W. Gagne Apr 26 '13 at 12:16
  • To add, I'm assuming this is correct so I'll be happy to accept this answer unless anyone can provide a solution to the question I originally asked in the next few day. I've started looking for manual workarounds and posted this at serverfault.com/questions/502898/ddns-client-for-windows – Elijah W. Gagne Apr 28 '13 at 15:16

What's the logic behind this requirement from the sysadmin side?

The cluster is going to register the DNS in the same domain that the cluster exists in, not a subdomain of the domain that the cluster is in. You can put a CNAME in place in sql.company.com that points to your DNS name in company.com, but you'll need to be able to update the DNS record in company.com for the cluster to work correctly.

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  • Editing DNS records in the company.com zone has the potential to affect 10's of thousands of records. The Network Team is trying to scope DNS write permissions to a limited zone that would only affect SQL Servers. – Elijah W. Gagne Apr 26 '13 at 12:18
  • By default in Windows DNS the machine that creates the DNS record is the only one that can change the DNS record. All computers that exist within the domain have the ability to change their own DNS records within the company.com DNS zone. It sounds like the network team needs a better understanding of how AD DNS works and how Windows DNS is secured. They are making it a lot harder than it needs to be. – mrdenny Apr 28 '13 at 9:07
  • I don't know enough about the DNS, but we use BIND for our nameservers. My understanding is that they can give my IP address permission to update records in the company.com zone, but they can't make it more granular than that. I could definitely be wrong on that and can follow up next week after talking to them. They also suggested securing DNS write permissions using TSIGs, but based on the lack of responses I got at serverfault.com/questions/500342/… I don't think that's an option. – Elijah W. Gagne Apr 28 '13 at 15:12
  • Ah, you are using a non-standard DNS config which is why so few people are able to help you. Basically no one sets up their DNS this way which is why you aren't finding any useful answers. In a nut shell, they aren't going to get to secure things the way that they want. If they had gone with Microsoft's DNS servers everything would be much easier to configure, but using BIND you are going to be limited in what can be done. For the automatic failover between subnets to work the cluster has to update DNS. The other option is to update DNS manually and tell the cluster not to register DNS. – mrdenny Apr 29 '13 at 12:21
  • Considering that BIND has many times the market share that Microsoft has for DNS servers I'm not sure it could would be correct to call this a non-standard DNS config. I think it's a limitation of AlwaysOn Availability Groups that they do not give you the ability to configure the DNS domain you use for them. – Elijah W. Gagne Apr 29 '13 at 18:38

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