Network Diagnostics Using Net Config

When you’re having a problem accessing network resources, or displaying what network resources are available, Browstat is a good starting point. To check IP connectivity setting, you use IPConfig. Sometimes, though, neither “browstat status” nor “ipconfig /all” tells you what you need to know.

Starting from the lower level of the OSI Network Model, you look at the”ipconfig /all” log, and see a network connection, identified as:

Physical Address. . . . . . . . . : 00-04-76-D7-C5-6A

IP Address. . . . . . . . . . . . : 192.168.1.50

You suspect, but you can’t tell for sure, that that same connection is identified in the “browstat status” log, as:

Status for domain WORKGROUP on transport NetBT_Tcpip_{B7E18D15-D9B1-4295-9DAD-C733C695294F}

To correlate the information provided by “browstat status” and “ipconfig /all”, or in cases where IPConfig is irrelevant (such as where IPX/SPX must be used), you can use the “net config” commands:

net config server
net config workstation

As with any other command, you run it from the Command Window, which gives you the ability to redirect the output, to a text file, for analysis later. Since you’re running 2 commands, one after the other, be sure to concatenate the output from the second after the first. Only type the command into a command window – do not do Start – Run – “net config…”.

Let’s look at “net config” from my mythical computer, “PChuck1”.

First, “net config server”.

Server Name                           \\PChuck1
Server Comment                        Primary

Software version                      Windows 2002
Server is active on                   
 NetbiosSmb (000000000000)
 NetBT_Tcpip_{B7E18D15-D9B1-4295-9DAD-C733C695294F} (000476D7C56A)


Server hidden                         No
Maximum Logged On Users               10
Maximum open files per session        16384

Idle session time (min)               15
The command completed successfully.

Next, “net config workstation”.

Computer name                        \\PChuck1
Full Computer name                   PChuck1.martinez.cacroll.net
User name                            pchuck

Workstation active on                
 NetbiosSmb (000000000000)
 NetBT_Tcpip_{B7E18D15-D9B1-4295-9DAD-C733C695294F} (000476D7C56A)

Software version                     Windows 2002

Workstation domain                   PChuck
Workstation Domain DNS Name          pchuck.local
Logon domain                         PChuck

COM Open Timeout (sec)               0
COM Send Count (byte)                16
COM Send Timeout (msec)              250
The command completed successfully.

What does all of this tell us?

  • First,

    Computer name \\PChuck1

    PChuck1 is the name of the computer, which matches the browstat and ipconfig logs.

  • Next,

    Server is active on
    NetbiosSmb (000000000000)
    NetBT_Tcpip_{B7E18D15-D9B1-4295-9DAD-C733C695294F} (000476D7C56A)

    Shows us two key items:

    • The network connection is using NetBT and SMB. This is a normal binding list.
      • If there was only an entry for “NetbiosSmb”, file sharing would work, but access by name will be a problem. Always Enable NetBT for best results.
      • If there was an entry for “NwlnkIpx” and / or “NwlnkNb”, file sharing MAY work, but irregularly.
    • The entry

      NetBT_Tcpip_{B7E18D15-D9B1-4295-9DAD-C733C695294F}

      as shown in “browstat status”, corresponds to MAC address

      000476D7C56A

      as shown in “ipconfig /all”.

  • A small, but still important detail,

    Server hidden No

    tells us that the server is intended to be visible in Network Neighborhood.

  • And some more details,

    Maximum Logged On Users 10
    Maximum open files per session 16384

    Idle session time (min) 15

    may tell us why all of the computers in the workgroup can’t access shares on the server simultaneously.

  • Finally,

    Workstation domain PChuck
    Logon domain PChuck

    Shows that this computer is a member of domain (or workgroup) PChuck, and is logged on to domain PChuck. If your domains and workstations are named with some thought, this likely indicates that the computer in question is logged in to domain PChuck. On the other hand, if we had

    Workstation domain PChuck
    Logon domain PChuck1

    then we know that this computer is a member of domain (or workgroup) PChuck; but, in this case, the computer is logged on locally, to PChuck1. Note that since you can generally logon locally to any computer, even if it’s a domain member, we still cannot tell if it’s a domain or workgroup member.

A Gratuitous Protocol
But look closely at the list of protocol bindings. If “net config server” shows us, for instance,

Server is active on                   
 NwlnkIpx (000000000001)
 NwlnkNb (0016f004143e)
 NetBT_Tcpip_{747CE691-1460-4F27-AB2F-F19C2110CCFB} (0016f004143e)
 NetbiosSmb (000000000000)

Here we see another example of the presence of IPX/SPX (“NwlnkIpx”), and of NetBEUI (“NwlnkNb”). If you’re having problems, which I presume is why you’re here, always start by removing IPX/SPX and / or NetBEUI.

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