SMS: Network Discovery Causes Incorrect Names to Appear in Collections (244335)

SYMPTOMS

When Network Discovery is run in an environment where Domain Name Server (DNS) reverse lookup zones are used, the discovered data shown in the collections may not reflect the correct name for recently discovered systems.

CAUSE

When Network Discovery receives a list of Internet Protocol (IP) addresses from the Address Resolution Protocol (ARP) cache of a router, it uses DNS reverse lookup to determine the name of each device. If the first portion of the fully qualified domain name (FQDN) in the DNS reverse lookup table does not match a system's NetBIOS name, the name in the reverse lookup table could be incorrectly used as the system's NetBIOS name.

WORKAROUND

Network Discovery runs only on the Microsoft Systems Management Server when it is scheduled or requested.

NOTE: Windows Networking Logon Discovery can be used to discover clients on the network as well.

To work around this issue, do one of the following:

Ensure that the DNS reverse lookup tables contain accurate FQDNs for the systems in your network environment.
Configure the Systems Management Server site's Transmission Control Protocol/Internet Protocol (TCP/IP) properties not to use DNS servers. If Dynamic Host Configuration Protocol (DHCP) is used to configure the server's IP address and DNS server configuration, it may be necessary to disable DHCP and define a static IP address for the server to control the DNS server configuration.

MORE INFORMATION

This issue can also occur if specifying a Microsoft Windows NT system's IP address as a Simple Network Management Protocol (SNMP) device under the Network Discovery properties.

The following example shows how this problem can occur:

NetBIOS name:  BIGBIRD
IP address: 121.54.34.222 
DNS PTR record:  121.54.34.222
Returned name: sesame.street.com

When Network Discovery asks the DNS server to return the name that matches the 121.54.34.222 IP address, it receives "sesame.street.com". The portion of the name up to the first period is used as a resource name for this device. As a result, "sesame" appears as the name of this system, not "BIGBIRD".

If Windows NT Remote Client Installation is enabled when this behavior occurs, the Systems Management Server Client Configuration Manager component may try to install the Systems Management Server client on systems that either do not exist or are incorrectly discovered.