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.
