DHCP - obscure error message

[Guest Terry Pinnell]

In Event Viewer I see many errors like this

---------

DHCP

"The IP address lease 192.168.x.xx for the Network Card with network

address xxxxxxxxxx has been denied by the DHCP server 192.168.1.1 (The

DHCP Server sent a DHCPNACK message)." [i've inserted the x's for

security.]

---------

 

Totally meaningless to me! Any of the experts able to help please?

 

--

Terry, East Grinstead, UK

[Guest Whiskers]

Re: DHCP - obscure error message

 

["Followup-To:" header set to 24hoursupport.helpdesk.]

On 2008-07-17, Terry Pinnell <terrypinDELETE@THESEdial.pipex.com> wrote:

> In Event Viewer I see many errors like this

> ---------

> DHCP

> "The IP address lease 192.168.x.xx for the Network Card with network

> address xxxxxxxxxx has been denied by the DHCP server 192.168.1.1 (The

> DHCP Server sent a DHCPNACK message)." [i've inserted the x's for

> security.]

> ---------

>

> Totally meaningless to me! Any of the experts able to help please?

 

 

<http://www.ex-designz.net/tcpipguide.asp>:-

 

LEASE RENEWAL

DHCP clients will attempt to renew their leases when %50 of the lease

has expired. The client will send a DHCPREQUEST message to the server

that assigned the lease. Assuming the DHCP server isn't on fire or

anything it will send out a DHCPACK with the new lease. If the server

is unavailable, then the client can continue functioning as it has %50

remaining still. The client will continue as normal until the lease

reaches %87.5 used at which time it broadcast to all DHCP servers and

attempt to get a new lease. If the client receives a DHCPNACK message

or the lease expires then the client must start all over again and will

get a different IP address. If the lease expires and the client is

unable to get a new one then the user will be whining to their IS dept.

about it because they will not be able to communicate over the network.

 

 

See also

<http://www.microsoft.com/technet/support/ee/SearchResults.aspx?Type=0&Message=dhcpnack>

 

--

-- ^^^^^^^^^^

-- Whiskers

-- ~~~~~~~~~~

[Guest Gerry]

Re: DHCP - obscure error message

 

You're the cat's whiskers <G>. When I saw Terry's question I did not

expect such an formative reply!

 

 

 

~~~~

 

 

Gerry

~~~~

FCA

Stourport, England

Enquire, plan and execute

~~~~~~~~~~~~~~~~~~~

Whiskers wrote:

> ["Followup-To:" header set to 24hoursupport.helpdesk.]

> On 2008-07-17, Terry Pinnell <terrypinDELETE@THESEdial.pipex.com>

> wrote:

>> In Event Viewer I see many errors like this

>> ---------

>> DHCP

>> "The IP address lease 192.168.x.xx for the Network Card with network

>> address xxxxxxxxxx has been denied by the DHCP server 192.168.1.1

>> (The DHCP Server sent a DHCPNACK message)." [i've inserted the x's

>> for security.]

>> ---------

>>

>> Totally meaningless to me! Any of the experts able to help please?

>

>

> <http://www.ex-designz.net/tcpipguide.asp>:-

>

> LEASE RENEWAL

> DHCP clients will attempt to renew their leases when %50 of the

> lease has expired. The client will send a DHCPREQUEST message to

> the server that assigned the lease. Assuming the DHCP server

> isn't on fire or anything it will send out a DHCPACK with the new

> lease. If the server is unavailable, then the client can continue

> functioning as it has %50 remaining still. The client will

> continue as normal until the lease reaches %87.5 used at which

> time it broadcast to all DHCP servers and attempt to get a new

> lease. If the client receives a DHCPNACK message or the lease

> expires then the client must start all over again and will get a

> different IP address. If the lease expires and the client is

> unable to get a new one then the user will be whining to their IS

> dept. about it because they will not be able to communicate over the

> network.

>

>

> See also

> <http://www.microsoft.com/technet/support/ee/SearchResults.aspx?Type=0&Message=dhcpnack>

[Guest John Wunderlich]

Re: DHCP - obscure error message

 

Terry Pinnell <terrypinDELETE@THESEdial.pipex.com> wrote in

news:vitt745d2p3bgfidid2l3eo9eet5uih40q@4ax.com:

> In Event Viewer I see many errors like this

> ---------

> DHCP

> "The IP address lease 192.168.x.xx for the Network Card with

> network address xxxxxxxxxx has been denied by the DHCP server

> 192.168.1.1 (The DHCP Server sent a DHCPNACK message)." [i've

> inserted the x's for security.]

> ---------

>

> Totally meaningless to me! Any of the experts able to help please?

>

 

Is this a laptop that often moves from one network to another?

When contacting a DHCP server for an IP address, the computer usually

expresses a preference for the last IP address that it had. If the

DHCP server determines that that IP address is currently unavailable

or that the requested address does not belong to the subnet served by

the DHCP server, then you will log the error that you cite in the

Event Viewer. This is perfectly normal and simply indicates that the

"quick" DHCP assignment failed and that the regular DHCP assignment

process is being forced.

 

HTH,

John

[Guest Terry Pinnell]

Re: DHCP - obscure error message

 

John Wunderlich <jwunderlich@lycos.com> wrote:

>Terry Pinnell <terrypinDELETE@THESEdial.pipex.com> wrote in

>news:vitt745d2p3bgfidid2l3eo9eet5uih40q@4ax.com:

>

>> In Event Viewer I see many errors like this

>> ---------

>> DHCP

>> "The IP address lease 192.168.x.xx for the Network Card with

>> network address xxxxxxxxxx has been denied by the DHCP server

>> 192.168.1.1 (The DHCP Server sent a DHCPNACK message)." [i've

>> inserted the x's for security.]

>> ---------

>>

>> Totally meaningless to me! Any of the experts able to help please?

>>

>

>Is this a laptop that often moves from one network to another?

>When contacting a DHCP server for an IP address, the computer usually

>expresses a preference for the last IP address that it had. If the

>DHCP server determines that that IP address is currently unavailable

>or that the requested address does not belong to the subnet served by

>the DHCP server, then you will log the error that you cite in the

>Event Viewer. This is perfectly normal and simply indicates that the

>"quick" DHCP assignment failed and that the regular DHCP assignment

>process is being forced.

>

>HTH,

> John

 

Thanks John. This is just a WinXP desktop PC, and I'm the sole user.

The only 'network' is my BT Broadband connection and a cable

connecting my old PC to my router temporarily, to allow copying of

files. What and where is 'the DHCP server' that makes these choices

please?

 

Must say I do find this stuff very hard going! But if I've got the

drift of what you're saying, then it sounds like I don't need to

worry? Some 'lease' or other is not about to come to a sudden halt,

excommunicating me (literally) from the Net?

 

--

Terry, East Grinstead, UK

[Guest John Wunderlich]

Re: DHCP - obscure error message

 

Terry Pinnell <terrypinDELETE@THESEdial.pipex.com> wrote in

news:jp74841ik9d0a6lkcpvn1c7iesskbt58ag@4ax.com:

> John Wunderlich <jwunderlich@lycos.com> wrote:

>

>> Terry Pinnell <terrypinDELETE@THESEdial.pipex.com> wrote in

>> news:vitt745d2p3bgfidid2l3eo9eet5uih40q@4ax.com:

>>

>>> In Event Viewer I see many errors like this

>>> ---------

>>> DHCP

>>> "The IP address lease 192.168.x.xx for the Network Card with

>>> network address xxxxxxxxxx has been denied by the DHCP server

>>> 192.168.1.1 (The DHCP Server sent a DHCPNACK message)." [i've

>>> inserted the x's for security.]

>>> ---------

>>>

>>> Totally meaningless to me! Any of the experts able to help

>>> please?

>>>

>>

>> Is this a laptop that often moves from one network to another?

>> When contacting a DHCP server for an IP address, the computer

>> usually expresses a preference for the last IP address that it

>> had. If the DHCP server determines that that IP address is

>> currently unavailable or that the requested address does not

>> belong to the subnet served by the DHCP server, then you will log

>> the error that you cite in the Event Viewer. This is perfectly

>> normal and simply indicates that the "quick" DHCP assignment

>> failed and that the regular DHCP assignment process is being

>> forced.

>>

>> HTH,

>> John

>

> Thanks John. This is just a WinXP desktop PC, and I'm the sole

> user. The only 'network' is my BT Broadband connection and a cable

> connecting my old PC to my router temporarily, to allow copying of

> files. What and where is 'the DHCP server' that makes these

> choices please?

>

> Must say I do find this stuff very hard going! But if I've got the

> drift of what you're saying, then it sounds like I don't need to

> worry? Some 'lease' or other is not about to come to a sudden

> halt, excommunicating me (literally) from the Net?

>

 

The DHCP Server is the program that assigns you your IP address when

you connect to the network. If you connect directly to your

Broadband connection, the DHCP server is managed by your ISP. If you

connect to a router, then the router provides the DHCP function.

Connecting to a router, you usually get an IP address like

192.168.x.x. Connecting to your broadband, you would get a different

IP address. When your computer asks the DHCP server for an IP

address, it usually tries to take a shortcut by saying something like

"I need an IP address and, by the way, I'd prefer the last IP address

I had which was X.X.X.X" It would not be unusual for the DHCP server

to reply saying "I'm sorry but X.X.X.X is not currently available".

When this happens, you get the message that you see in your Event Log

and your computer will ask again for an IP address but this time it

will not express a preference.

 

When assigned an IP address via DHCP, there will be a time limit on

the use of this IP address. This is the "lease" time. Routers will

usually default to about a week, and ISPs will default anywhere

between a couple of hours to a couple of days. You can see your

lease expiration by bringing up a command window (start->run->cmd)

and entering the command: ipconfig /all

When the lease is half-over, your computer will automatically attempt

to renew the lease. It is rare for a lease not to renew; however,

should it not renew before it expires, yes you will be (as you put

it) excommunicated from the network. The main reason for the lease

is that should you drop off the network without formally releasing an

IP address, that IP address will eventually automatically expire and

revert back into the pool for assignment to another user.

 

HTH,

John