DNS: At least one name server in the list of root hints must respond to queries for the root zone
Updated: July 27, 2011
Applies To: Windows 7, Windows Server 2008, Windows Server 2008 R2, Windows Server 2012
This topic is intended to address a specific issue identified by a Microsoft Baseline Configuration Analyzer or Best Practices Analyzer scan. You should apply the information in this topic only to computers that have had the DNS Microsoft Baseline Configuration Analyzer or DNS Best Practices Analyzer run against them and are experiencing the issue addressed by this topic. For more information about best practices and scans, see Best Practices Analyzer.
Operating System |
Windows Server 2008, Windows Server 2008 R2, Windows Server 2012 |
Product/Feature |
DNS |
Severity |
Critical |
Category |
Operation |
Issue
All root hints failed an NS query for the root zone.
Recursion is enabled on the DNS server, but none of the root name servers are responding to a query for the root zone.
Impact
The DNS server might be unable to resolve external host names.
If forwarders are unavailable, DNS client computers will be unable to resolve external host names.
Resolution
Configure the list of root hints with name servers that are responding.
Update the list of root hints to include only those servers that respond to a query for the root zone.
Membership in Administrators, or equivalent, is the minimum required to complete these procedures. Review details about using the appropriate accounts and group memberships at Local and Domain Default Groups (https://go.microsoft.com/fwlink/?LinkId=83477).
To verify a root name server
Open an elevated command prompt.
Type the following command, and then press ENTER:
nslookup –type=ns . <root name server>Replace <root name server> with the IP address of the root hint server that you wish to verify. If the root name server is valid, a list of authoritative servers for the root zone (root name servers) will be displayed.
To configure Root Hints
Click Start, click Run, type dnsmgmt.msc, and then press ENTER. The DNS Manager console will open.
In the console tree, click the name of the DNS server you wish to configure.
On the Action menu, click Properties.
Click the Root Hints tab.
Modify server root hints as follows:
To add a root server to the list, click Add, and then specify the name and IP address of the server to be added to the list.
To modify a root server in the list, click Edit, and then specify the name and IP address of the server to be modified in the list.
To remove a root server from the list, select it in the list, and then click Remove.
To copy root hints from a DNS server, click Copy from server, and then specify the IP address of the DNS server from which you want to copy a list of root servers to use in resolving queries. These root hints will not overwrite any existing root hints.
Additional considerations
The following is the default list of root hints.
a.root-servers.net. 198.41.0.4
b.root-servers.net. 192.228.79.201
c.root-servers.net. 192.33.4.12
d.root-servers.net. 128.8.10.90
e.root-servers.net. 192.203.230.10
f.root-servers.net. 192.5.5.241
g.root-servers.net. 192.112.36.4
h.root-servers.net. 128.63.2.53
i.root-servers.net. 192.36.148.17
j.root-servers.net. 192.58.128.30
k.root-servers.net. 193.0.14.129
l.root-servers.net. 199.7.83.42
m.root-servers.net. 202.12.27.33
Tip
An updated list of root hints is available at ftp://ftp.rs.internic.net/domain/db.cache.