Preventing DHCP IP assignment to clients with certain MAC addresse

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Guest

Is there anyway to setup DHCP on W2K3 Server to not assign IP addresses to
devices with certain MAC address pattern (i.e. first 5 characters) or even
vice versa (only assign to those that meet a certain pattern)? I had heard
something about using classes and even the ability to assign IP addresses to
only laptops. I don't know how the DHCP server would know that the client
requesting for an address is a laptop unless DHCP server is AD-Authorized and
the laptops are in a certain OU and somehow, in the DHCP server, the scope
was associated with that certain OU, or some clever way. Please let me know
if restricting the address assignment is even possible? Thanks.

BTW, we are trying to stop printers from grabbing addresses from our DHCP
server, and only use DHCP for XP clients that are not part of the domain yet.
We use the dynamic addresses during imaging (not using RIS), and by the time
the client is joined to AD, they are manually assigned an IP.
 
Parhez Sattar said:
BTW, we are trying to stop printers from grabbing addresses from our DHCP
server, and only use DHCP for XP clients that are not part of the domain
Click to expand...
yet.

Give the printers static addresses and be done with it. The printers should
always be staticly addressed to begin with. All hosts that make up the
network infrastucture (hubs, switches, printers, routers, firewalls,
servers) should be running static addressing. You don't want the whole
network going belly up one morning because the DHCP Server went down in the
middle of the night. DHCP should only be used for Client Workstations and
other "non-essential" devices.
 
I fully agree with you, Phillip. However, our problem comes from the fact
that the printers are placed by a tech and then configured (manually assign
IP, etc.) by the Network Administrator who uses the JetAdmin Utility (all
printers are HP) from his workstation. Before he can do that, the printer
already has an IP address it grabbed from the DHCP server, as the printers
always come with that option turned on. Yes, we could train the tech to
disable (Set to NO) the DHCP client option on the printer when it is placed.
However, that is not always practical since sometimes the printer is placed
by a department manager.
So, Phillip, there is no way to "exclude" a MAC address-range (by pattern)
 
Parhez Sattar said:
I fully agree with you, Phillip. However, our problem comes from the fact
that the printers are placed by a tech and then configured (manually assign
IP, etc.) by the Network Administrator who uses the JetAdmin Utility (all
printers are HP) from his workstation. Before he can do that, the printer
already has an IP address it grabbed from the DHCP server, as the printers
always come with that option turned on. Yes, we could train the tech to
disable (Set to NO) the DHCP client option on the printer when it is placed.
However, that is not always practical since sometimes the printer is placed
by a department manager.
So, Phillip, there is no way to "exclude" a MAC address-range (by pattern)
on the DHCP server?
Click to expand...

No, there is no way to do that.

What I always do is this (I don't bother with "JetAdmin"):

1. Start the printer up on my network.
2. Look at the leases in the DHCP to see what address the printer was given
when I started it up.
3. Use a web browser to "open" the build in web interface that nearly all
printer NICs have. If let's say, the printer was given 192.168.15.86, then
I use a browser and go to http://192.168.15.86 . Be patient, they can be
very slow in loading.
4. If the Web interface doesn't work,..it can also be done with telnet.
5. Use the web interface to change it to the desired static IP#

A typical HP Printer Telnet session will look like this after typing "?" to
see the help:
----------------------------------------------------------------------------
--------------------
Please type "?" for HELP, or "/" for current settings
?
Click to expand...

To Change/Configure Parameters Enter:
Parameter-name: value <Carriage Return>

Parameter-name Type of value
ip: IP-address in dotted notation
subnet-mask: address in dotted notation
default-gw: address in dotted notation
syslog-svr: address in dotted notation
idle-timeout: seconds in integers
set-cmnty-name: alpha-numeric string (32 chars max)
host-name: alpha-numeric string (upper case only, 32 chars max)
dhcp-config: 0 to disable, 1 to enable
ipx/spx: 0 to disable, 1 to enable
dlc/llc: 0 to disable, 1 to enable
ethertalk: 0 to disable, 1 to enable
banner: 0 to disable, 1 to enable

Type passwd to change the password.

Type "?" for HELP, "/" for current settings or "quit" to save-and-exit.
Or type "exit" to exit without saving configuration parameter entries----------------------------------------------------------------------------
---------------------

Using the "/" to see current settings may look like this (I faked the
addresses and hostname):
----------------------------------------------------------------------------
----------------------
HP JetDirect

Please type "?" for HELP, or "/" for current settings
/
Click to expand...

===JetDirect Telnet Configuration===
Firmware Rev. : G.07.03
MAC Address : 00:60:b0:c8:77:7f
Config By : USER SPECIFIED

IP Address : 192.168.140.122
Subnet Mask : 255.255.255.0
Default Gateway : 192.168.140.1
Syslog Server : Not Specified
Idle Timeout : 120 Seconds
Set Cmnty Name : Not Specified
Host Name : MY-PRINTER

DHCP Config : Disabled
Passwd : Disabled
IPX/SPX : Disabled
DLC/LLC : Disabled
Ethertalk : Disabled
Banner page : Enabled
 
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