1. Getting the Media Access Control Information with the GetMAC Utility
Every network adapter
has a Media Access Control (MAC) address. The address is unique for
every network adapter across all vendors. The output from this utility
consists of the network adapter MAC address and the transport name
associated with it. You don't gain much in the way of additional
information. However, the MAC address is central to all kinds of
monitoring activity, including sniffing packets on your network (the act
of filtering the packets and viewing the ones of interest). This
utility uses the following syntax:
GETMAC [/S system [/U [domain\]user [/P [password]]]]
[/FO {TABLE | LIST | CSV}] [/NH] [/V]
The following describes the command line arguments.
/S
systemSpecifies the remote system that you want to check. In most cases, you'll also need to supply the /U and the /P command line switches when using this switch.
/U
[domain\]userSpecifies the
username on the remote system. This name may not match the username on
the local system. You'll need to supply a domain name when working with a
domain controller.
/P
[password]Specifies the
password for the given user. You can provide the command line switch
without specifying the password on the command line in cleartext. The
system prompts you for the password. Using this feature can help you
maintain the security of passwords used on your system.
/FO {TABLE | LIST | CSV}
Defines the output
provided by the utility. The table format is normally the easiest to
view on screen. The table columns define the values for output, while
each row contains one driver entry. The Comma Separated Value (CSV)
output provides the best method for preparing the data for entry in a
database. Use redirection to output the CSV data to a file and then import it to
your database. The list format provides one data element per line. Each
group of data elements defines one driver. The utility separates each
driver by one blank line. Some people find the list format more readable
when working in verbose mode since the table format requires multiple
lines for each entry (the lines wrap).
/NH
Forces the
utility to display the data without a column header. You can only use
this command line switch with the table and CSV formats. Omitting the
header makes it easier to incorporate the data in a report or import it
into a database.
/V
Displays
detailed data about each of the network adapters. In addition to the
standard output, the utility provides the human-readable connection name
and network adapter name. Using this command line switch makes it a lot
easier to associate a particular MAC address with a specific network
adapter (making monitoring easier as well).
2. Managing the Network with the Net Utility
The Net utility represents
one of the most flexible and comprehensive means of controlling all
aspects of your network. Given all that it does, it's not surprising
that the Net utility relies on several operating modes to perform tasks.
For example, you manage user accounts using the Accounts mode. The Net
utility modes include Accounts, Computer, Config, Continue, File, Group,
Help, HelpMsg, LocalGroup, Name, Pause, Print, Send, Session, Share,
Start, Statistics, Stop, Time, Use, User, and View. The following
sections describe each of these modes.
NOTE
If you find that you need help with the Net utility, you can't use the standard practice of typing /?. The /? command line switch provides extremely limited help. Instead, you need to type Net Help Mode at the command line and press Enter. For example, to obtain help on using the Accounts mode, type Net Help Accounts and press Enter.
2.1. ACCOUNTS
Use the ACCOUNTS mode to
modify all user accounts on a system with specific settings. For
example, you can define all user accounts to have a maximum password age
of so many days. This mode only affects existing user accounts—not user
accounts that you create in the future. Typing Net Accounts by itself displays the current settings. This mode uses the following syntax:
NET ACCOUNTS [/FORCELOGOFF:{minutes | NO}] [/MINPWLEN:length]
[/MAXPWAGE:{days | UNLIMITED}] [/MINPWAGE:days] [/UNIQUEPW:number]
[/DOMAIN]
The following list describes each of the command line arguments.
/FORCELOGOFF:{minutes | NO}
Sets the number
of minutes before the system forces a user to log off after the user's
account or valid logon hours expire. The default setting of NO prevents
forced logoff.
/MINPWLEN:
lengthSets the
minimum number of characters in a password. The default setting is 6
characters. You may use any value between 0 and 14 characters.
/MAXPWAGE:{days | UNLIMITED}
Sets the maximum number of days between password changes. You may define no password change requirement by using the UNLIMITED argument. The /MAXPWAGE setting must always exceed the /MINPWAGE setting. The default setting is 90 days. You may use any value between 1 and 999 days.
/MINPWAGE:
daysSets the minimum
number of days that must pass before a user can change their password. A
value of 0 sets non-minimum time. The /MAXPWAGE setting must always exceed the /MINPWAGE setting. The default setting is 0 days. You may use any value between 0 and 999 days.
/UNIQUEPW:
numberSpecifies that the
user must provide a unique password for each password change through the
number specified. For example, if you specify 5, then the system tracks
five of the user's passwords and allows the user to reuse a password on
the sixth change. The maximum value is 24.
/DOMAIN
Performs the task on a domain control for the current domain. Otherwise, any task affects only the local computer.
2.2. COMPUTER
Use the COMPUTER mode to
add a computer to the domain database or delete it from the database.
You can only use this mode on a server. This mode uses the following
syntax:
NET COMPUTER \\computername {/ADD | /DEL}
The following list describes each of the command line arguments.
\\computername
Specifies the
Universal Naming Convention (UNC) name of the computer to add or delete.
Always use the computer's name as it appears to the network.
/ADD
Adds the specified computer to the domain.
/DEL
Removes the specified computer from the domain.
2.3. CONFIG
Use the CONFIG mode to
discover network configuration information for the current machine.
When used alone, this mode displays the configurable services on a
machine. This mode uses the following syntax:
NET CONFIG [SERVER | WORKSTATION]
The following list describes each of the command line arguments.
Server
Displays
information about the configuration of the server service. This
information includes the server name, server comment, software version,
network node information, whether the server is hidden, the maximum
number of users that can log in, the maximum number of available file
handles per session, and the idle session time.
Workstation
Displays
information about the configuration of the workstation service. This
information includes computer UNC name, full computer name, username,
network node information, software version, workstation domain,
workstation Domain Name Service (DNS) name, logon domain, and COM
statistics.
2.4. CONFIG SERVER
You can use the CONFIG
SERVER mode to adjust a few, but not all, of the server configuration
features. This mode uses the following syntax:
NET CONFIG SERVER [/AUTODISCONNECT:time] [/SRVCOMMENT:"text"] [/HIDDEN:{YES | NO}]
The following list describes each of the command line arguments.
/AUTODISCONNECT:
timeSets the maximum
number of minutes that a user's session remains inactive before the
server disconnects it. Use a value of −1 to force the system to remain
connected indefinitely. You may use any value from −1 to 65,535 minutes.
The default setting is 15 minutes.
/SRVCOMMENT:
"text"Adds a comment to the
server information. The comment appears in all graphical displays and
in the Net View mode. You may use up to 48 characters for the comment.
Always enclose comments in quotes.
/HIDDEN:{YES | NO}
Determines
whether the server appears in the display listing for servers. Using
this feature can prevent unauthorized users from finding a server on
your network since the user would need to know the server name to access
it. However, this setting doesn't change the server security. You still
have to set security aggressively to protect your server. The default
setting is NO.