DHCP will not update DNS with IP of clients however WINS shows correct IP address

December 7th, 2009

In Windows 2003 DHCP can update DNS on behalf of the client unless the client has the TCP/IP option “Register this connection’s addresses in DNS” enabled (this will always override DHCP registration).

Depending which option above is in operation depends on whether the client or DHCP server ’owns’ the DNS record, this is worth bearing in mind during troubleshooting as only the owner of the record can update it in DNS.

DNS has the option to query WINS for any records it is unable to locate in its own database (Open DNS and select the zone required and right click for properties, from the WINS tab tick the option ‘Use WINS forward lookup’) and as such DNS can appear to provide the correct IP address even if the record is not present (DNS can return an IP address and a host name with a different domain suffix as WINS is not constrained by the DNS namespace).

If you have clients that are not updating DNS try the following from the client’s command prompt:

c:\ipconfig /regsiterdns

You may have to wait 15 minutes for it to correctly register it’s name and IP address and you can check the Event Logs for verification.

If this does not resolve the issue and you are using DHCP to register on behalf of clients then check the AD Group called “DnsUpdateProxy”. Make sure that all DNS servers are listed in the members tab. this issue can occur when a sys admin relocates a DNS server to a new machine and does not update this group with the new server name.

Tags: , , ,
Posted in Windows Server | No Comments »



WSUS - How to force Windows Updates from the command line

September 26th, 2008
Manipulate Automatic Updates Behavior Using Command-line Options

There are two documented command-line options used for manipulating Automatic Updates behavior. These options are meant to be run from a command prompt. They are helpful for testing and troubleshooting client computers. For comprehensive troubleshooting information for problems with both the WSUS server and client computers, see “Microsoft Windows Server Update Services Operations Guide.”

Detectnow Option

Because waiting for detection to start can be a time-consuming process, an option has been added to allow you to initiate detection right away. On one of the computers with the new Automatic Update client installed, run the following command at the command prompt:

wuauclt.exe /detectnow

Resetauthorization Option

WSUS uses a cookie on client computers to store various types of information, including computer group membership when client-side targeting is used. By default this cookie expires an hour after WSUS creates it. If you are using client-side targeting and change group membership, use this option in combination with detectnow to expire the cookie, initiate detection, and have WSUS update computer group membership.

Note that when combining parameters, you can use them only in the order specified as follows:

wuauclt.exe /resetauthorization /detectnow

Tags: , ,
Posted in Windows Server | No Comments »

« Older Entries