Infralin's (not so) Frequently Asked Questions on IP networking

Gijsbert van der Linden ()
   
Infralin Consultancy (http://www.infralin.com)
    Last updated: 2-11-2002

The findings included in this document are based on Windows 2000 Advanced Server with Service Pack 2.

 

What source address is used when a packet is originating from a multi-homed node or from a network interface with multiple IP addresses?

The source address is used that corresponds with the subnet the IP packet is sent over. When a Network interface has e.g. the IP addresses 172.16.0.1/24 and 172.18.0.1/24 and a packet is destined to 172.18.0.2, the source address becomes 172.18.0.1.

When a packet is sent in response to another packet the source address of the response packet becomes the target address of the original packet, irrespective of the interface used to send the packet.

How to see which ports are open?

Type in a command box: netstat -n

 

How to verify the Domain Records in a WINS system?

Type in a command box: netsh wins server \\<WINS server> check name namefile=c:\names.txt serverfile=servers.txt

 

How to find the DCs handling a Domain?

Type in a command box: netdiag /debug /d:<Domain> (add /l for keeping a log file in netdiag.log)

 

How to find Netbios names resolved by a node?

Type in a command box: nbtstat and choose one of the options.