How can
I create an MS-DOS network boot
disk in Windows 2000?
|
Windows NT has the Network client creation utility
(ncadmin.exe) that lets you create floppy disks
that have network support. Microsoft dropped this
utility in Win2K and replaced it with Microsoft
Remote Installation Services (RIS). However, ncadmin.exe
still works under Win2K. You can copy the following
files from an NT server to a Win2K machine to use
the utility:
- Ncadmin.cnt
- Ncadmin.exe
- Ncadmin.hlp
If you don't have an NT server to copy the files
from, perform the following steps:
- Create a folder on your Win2K machine for the
three files you'll need.
- Insert your NT Server CD-ROM.
- Go to the i386 folder on the CD-ROM.
- Copy the following files to the folder you created
on the Win2K machine:
- Ncadmin.cn_
- Ncadmin.ex_
- Ncadmin.hl_
- Use the following command to expand the files:
C:\ncadmin>expand -r ncadmin.
How can
I enable load balancing with
multiple network adapter cards?
|
If you have two or more network adapter cards in
your system, you can use a randomizing algorithm
to distribute the number of connections or sessions
among the adapters. To use the algorithm, perform
the following steps:
- Start the registry editor (e.g., regedit.exe).
- Navigate to HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\
Services\NetBT\Parameters.
- From the Edit menu, select New - DWORD value.
- Enter a name of RandomAdapter, and press Enter.
- Double-click the new value, enter 1 to enable
or 0 to disable, and click OK.
- Close the registry editor.
- Reboot the machine.
How can
I get a list of MAC to IP addresses
on the network?
|
An easy way to get a list of MAC to IP addresses
on the local subnet is to ping every host on the
subnet and then check you ARP cache, however pinging
every individual node would take ages and the entries
only stay in the ARP cache for 2 minutes. An alternative
is to ping the broadcast mask of your subnet which
will ping every host on the local subnet (you can't
ping the entire network as you only communicate
directly with nodes on the same subnet, all other
requests are via the gateway so you would just get
a ARP entry for the gateway).
What is the broadcast mask? The broadcast mask
is easy to calculate if the subnet mask is in the
format 255.255.255.0 or 255.255.0.0 etc. (multiples
of 8 bits). For example if the IP address was 134.189.23.42
and the subnet mask was 255.255.0.0 the broadcast
mask would be 134.189.255.255, where 255 is in the
subnet mask the number from the IP address is copied
over, where 0 it is replaced with 255, basically
the network id part is kept. If the subnet mask
is not the basic 255.255 format, you should use
the following, all you need is the IP address and
the subnet mask
- For each bit set to 1 in the subnet mask, copy
the corresponding but from the IP address to the
broadcast mask
- For each bit set to 0 in the subnet mask, copy
a 1 into the corresponding bit of the broadcast
mask
for example, IP address 158.234.24.98 and subnet
mask 255.255.248.0
| Network |
Host |
| 1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
| 1 |
0 |
0 |
1 |
1 |
1 |
1 |
0 |
1 |
1 |
1 |
0 |
1 |
0 |
1 |
0 |
0 |
0 |
0 |
1 |
1 |
0 |
0 |
0 |
0 |
1 |
1 |
0 |
0 |
0 |
1 |
0 |
| 1 |
0 |
0 |
1 |
1 |
1 |
1 |
0 |
1 |
1 |
1 |
0 |
1 |
0 |
1 |
0 |
0 |
0 |
0 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
1 |
| Byte
1 |
Byte
2 |
Byte
3 |
Byte
4 |
The first row is the subnet mask 255.255.248.0,
the second row the IP
address 158.234.24.98 and the third row is the broadcast
mask, 158.234.31.255.
To get the MAC to IP addresses, you would therefore
perform the following
ping <broadcast mask>
arp -a
Voila, a list of IP addresses and their MAC address
(you can add > filename
to get the list to a file, e.g. arp -a > iptomac.lst).
You could repeat this exercise
on the various subnets of your organization.
Unfortunatly due to limitations in NT's implementation
of PING the above will
not work correctly so put the following into a file
REM arpping.bat
ping -n 1 -l 1 %1.%2
arp -a %1.%2
You can then call the batch file as follows:
C:\> for /l %i in (1,1,254)
do arpping 160.82.220 %i
In this case it would generate a list of all MAC
to IP
addresses for 160.82.220.1 to 160.82.220.254. Again
you could put this all in a file,
redirect to a file and then search, e.g.
REM test.bat
for /l %%i in (1,1,254) do arpping.bat 160.82.220
%%i
Notice you have to use two %%. You
could run as
C:\> test.bat > file.txt
Then search listing.txt for (example)
dynamic
C:\> findstr dynamic file.txt
160.82.220.1 00-00-0c-60-8b-41 dynamic
160.82.220.9 00-60-97-4b-bf-4c dynamic
160.82.220.13 00-10-4b-49-94-e1 dynamic
160.82.220.17 00-80-5f-d8-a4-8b dynamic
160.82.220.22 00-a0-d1-02-a4-cf dynamic
160.82.220.25 00-60-08-75-0d-7a dynamic
160.82.220.26 00-10-4b-44-e4-73 dynamic
160.82.220.33 00-10-4b-44-d6-33 dynamic
160.82.220.34 00-10-4b-4e-67-6a dynamic
160.82.220.35 00-60-97-4b-c4-53 dynamic
160.82.220.39 00-10-4b-44-eb-ae dynamic
160.82.220.41 00-10-4b-49-7b-f7 dynamic
160.82.220.42 00-00-f8-21-7a-7f dynamic
160.82.220.43 08-00-20-88-82-57 dynamic
160.82.220.221 00-80-5f-88-d0-55 dynamic
You can consolidate the last couple of steps so
you just create arpping.bat as before then just
issue command:
C:\>for /l %i in (1,1,254)
do arpping.bat 10.129.210 %i |findstr dynamic
C:\>arpping.bat 10.129.210 1 | findstr dynamic
10.129.210.1 00-08-c7-d3-24-f5 dynamic
C:\>arpping.bat 10.129.210 2 | findstr dynamic
10.129.210.2 00-08-c7-df-81-60 dynamic
C:\>arpping.bat 10.129.210 3 | findstr dynamic
10.129.210.3 00-80-5f-9b-ea-93 dynamic
C:\>arpping.bat 10.129.210 4 | findstr dynamic
10.129.210.4 00-80-5f-9b-36-ea dynamic
C:\>arpping.bat 10.129.210 5 | findstr dynamic
10.129.210.5 00-04-ac-37-78-92 dynamic
C:\>arpping.bat 10.129.210 6 | findstr dynamic
Notice we only use one % as we are not in a batch
file and it automatically only lists found entires
or you can use a combination of the different methods
to match your exact needs.
