Name Resolution and SharePoint

SharePoint uses name resolution to find other servers just like any other application.  But what happens when your infrastructure uses different types of name resolution?  Don’t think there would be a problem, right?  That’s what I thought.

When you set up your server’s OS (operating system) you configure its network setting to get them from a DHCP server and your DHCP server is configured to hand out only the IP address of your DNS servers, you are OK.  But if you are using both WINS and DNS and you have configured DHCP to hand out both—you may have an issue.  Here is what I ran into at a client.

The client utilizes WINS (in addition to DNS) as a name resolution service, but which caused some unforeseen issues. There are known issues using WINS with SharePoint and if one were to follow the guidelines in https://support.microsoft.com/default.aspx/kb/308913 most of the issues can be avoided.

One issue is not mentioned in the article; it deals with the NetBIOS naming of servers.  A NetBIOS name is combination of a 15 character (byte) name and a 16th character denoting the service compared to 255 or fewer characters for DNS host names. If you are running Windows Server 2003, the host name and the NetBIOS name on a computer are generated at the same time during installation. If the host name is more than 15 characters, the NetBIOS name is the first 15 characters of the host name, (which is better than it used to be, because it used to truncate the name to 13 characters and and a tilde and a number to the name).

In the case of SharePoint, if you are using both DNS and WINS, make *sure* that *both* names are registered in *BOTH* systems.  If any servers have names longer than 15 characters, take both the long name *and* the short name and register the A Record names in DNS.  If you don’t, SharePoint will use the truncated name from WINS and register that name in the configuration and content databases.  If this happens, name resolution may not work properly unless the truncated name is also registered with DNS.

“Not work Properly” – this is what I mean:

Example:  

Server1 (DNS) Name: PHX2-FILS-APP-01.company.com

Server2 (DNS) Name: PHX2-FILS-APP-02.company.com

Server1 (WINS) name: PHX2-FILS-APP-0 (This name gets registered in the Config DB)

Server2 (WINS) name: PHX2-FILS-APP~1 (This name gets registered in the Config DB)

If you register both the DNS and the WINS names you will be able to both access the server in the browser and you will have no issues with the databases.