PLEASE HELP: DHCPNACK error

Goobie

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Hello,

I have a new Netgear 3G router (MBR624GU) on my home LAN with 2 XP "server" PCs running 24hrs per day. These PCs reboot once per day. After rebooting and then exactly 12 hrs after that (I'm assuming that it is renewing the IP lease) both PCs record an error like this in the event viewer:

The IP address lease 192.168.0.3 for the Network Card with network address 00123530AB31 has been denied by the DHCP server 192.168.0.1 (The DHCP Server sent a DHCPNACK message).

With the one PC this is not much of an issue, however the other PC is a media streamer/PVR and when dropping the connection one irate wife glares at me until the connection is back up. I have since rescheduled the reboot so that 12 hours later the lease renewal stopped happening during 7e Laan. I have DHCP enabled in the router for assigning IPs to our laptops (and other gadgets), but assigned fixed IPs (easier to locate them with UltraVNC if the IP is fixed) to both these "server" PCs, in XP they are set to obtain IPs automatically.

How do I fix this?

Much appreciated
 
Dynamic vs Static ?

I have a new Netgear 3G router (MBR624GU) on my home LAN with 2 XP "server" PCs running 24hrs per day.
These PCs reboot once per day.
After rebooting and then exactly 12 hrs after that
(I'm assuming that it is renewing the IP lease) both PCs record an error like this in the event viewer:
1.) Far as I know there is no need to "reboot" a PC in order to renew a "lease" ???

The IP address lease 192.168.0.3 for the Network Card with network address 00123530AB31 has been denied by the DHCP server 192.168.0.1 (The DHCP Server sent a DHCPNACK message).
192.168.0.1 is your 3G modem -- DHCP server
192.168.0.3 is your XP "Server"?
Does this happen whilst rebooting is taking place ?
If so could just be the normal procedure of re-establishing a DHCP IP address ?

I have since rescheduled the reboot so that 12 hours later the lease renewal stopped happening during 7e Laan.

WHAT is scheduling the reboot ? -- this looks like the root cause

I have DHCP enabled in the router for assigning IPs to our laptops (and other gadgets),
but
assigned fixed IPs (easier to locate them with UltraVNC if the IP is fixed) to both these "server" PCs,

in XP they are set to obtain IPs automatically.

Hhhmm sems to be contradictory ?

Where do the fixed IP's come from ?

Are we looking at private vs public IP's ?

Your ISP assigns your PUBLIC IP's via IPCP

Internet Protocol Control Protocol

Your 3G router assigns your PRIVATE IP's via DHCP

You CANNOT have "fixed" IP's set on your XP as well as Dynamic IP's via your 3G DHCP


I think that you need to first find out WHY your machines are being rebooted.
 
I am considering that you have a form of 'internet connection sharing' enabled on one of the pc's, this will overrride the DCHP given address and provide it with a 192.168.1.x address (IIRC)
Check that ICS is turned off on the pc's and then reconfigure your router to have UPNP and DHCP on. - Long shot maybe, but thats what I can advise
 
I think that you need to first find out WHY your machines are being rebooted.

A long time ago I noticed that the software I'm running or XP itself became unstable after many hours of continuous up time. Therefore I simply prefer to have them reboot once per day, by scheduling the reboot through Scheduled Tasks. So I force them to reboot. The error occurs twice daily, once after reboot and then again 12 hours after that.

In my house I have 8 devices that can request an IP address from the router. Two of these are the server PCs. I access them using UltraVNC by entering their IP addresses into the software. I gave them fixed IP addresses 192.168.0.3 and ...0.4 as it is frustrating to find them on the network again if the router decides to give them a new IP address and I don't know what that is. Plus, the one PC is a CCTV server and I need port forwarding to access it from work. The rest of the devices on the network get their IP address automatically from the router. So basically a mixture of fixed and dynamic IP addresses on my home LAN.

This never happened before when I was using a DLink ADSL Router, so this cannot be part of the normal DHCP IP assignment.

Not using ICS.

thanks for the inputs
 
Reboot

A long time ago I noticed that the software I'm running or XP itself became unstable after many hours of continuous up time.
Therefore I simply prefer to have them reboot once per day, by scheduling the reboot through Scheduled Tasks.
So I force them to reboot.
The error occurs twice daily, once after reboot and then again 12 hours after that.

Strange software that ???

I have an old Socket 7 PC with Win 98SE that runs 24/7 ( unless the power is down for long or some such other problem )

I would STRONGLY suggest getting rid of whatever it is that is making your system unstable -- badly written software and memory leaks ?

A good and correctly configured XP PC should run for months without problems.

In my house I have 8 devices that can request an IP address from the router.
Two of these are the server PCs.

I access them using UltraVNC by entering their IP addresses into the software.

I gave them fixed IP addresses 192.168.0.3 and ...0.4 as it is frustrating to find them on the network again if the router decides to give them a new IP address and I don't know what that is.

There seems to be a conflict here --

Do you have a restricted range of IP addresses on the 3G router DHCP ?

If you have not done this and have DHCP PLUS a STATIC IP entered on the machine that is on the same subnet IP range then you are going to have problems.

Just use the DHCP IP range exclusion feature in the 3G router config.


Plus, the one PC is a CCTV server and I need port forwarding to access it from work.
The rest of the devices on the network get their IP address automatically from the router.
So basically a mixture of fixed and dynamic IP addresses on my home LAN.

OK -- but how is this mixture set up and allocated ????

This never happened before when I was using a DLink ADSL Router, so this cannot be part of the normal DHCP IP assignment.

Perhaps the DLink was correctly configured ?
 
Goobie : Some routers have the ability to "reserve" an IP for a certain MAC address.

So you can enter the MAC address on the router, along with what IP it should receive. Then you don't need to manually enter an IP on that device - it'll get the same IP assigned to it every time.

Your DHCP device, however, should be the only device that'll have a fixed IP. Rest can be all dynamic.
 
Goobie : Some routers have the ability to "reserve" an IP for a certain MAC address.

So you can enter the MAC address on the router, along with what IP it should receive. Then you don't need to manually enter an IP on that device - it'll get the same IP assigned to it every time.

Your DHCP device, however, should be the only device that'll have a fixed IP. Rest can be all dynamic.

Hey Lib, it would appear from googling that the problem is very common with Netgear routers. I found this: http://forum1.netgear.com/showthread.php?t=37038 which is almost identical to my problem. To see if it makes a difference, I have now set my servers up with a fixed IP address by configuring TCP/IP in XP (192.168.0.2 and 192.168.0.3). Before I only reserved these addresses in the router. I have also changed the DHCP range in the router to start from 192.168.0.4. Will let it run for a while to see if it works.
 
On your new router - Change the DHCP scope (range of addresses that it hands out to DHCP clients)
start address 192.168.1.150
end address 192.168.1.200

On your 2 XP boxes make sure they have a static IP each that DO NOT fall within the DHCP server scope.
XP PC1 - static IP - 192.168.1.10
XP PC2 - static IP - 192.168.1.11

Your 2 x XP boxes should not get DHCP errors at all (if they are using static IP's)
 
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