DHCP renewal of IP address with ISP denied

Hello

I wonder if anyone can advise concerning a series of messages appearing in the logs of my two networked computers?

Examples of the messages:

• ON ALPHA: The IP address lease 192.168.0.3 for the Network Card with network address 0x0024E8F1F44F has been denied by the DHCP server 192.168.0.1 (The DHCP Server sent a DHCPNACK message).
• On BETA: The IP address lease 192.168.0.2 for the Network Card with network address 0x7071BCA36DBF has been denied by the DHCP server 192.168.0.1 (The DHCP Server sent a DHCPNACK message).

The advent of either appears to kill my internet connection requiring a router restart. I should add that sometimes both PCs are on, but often only one is. In the latter case, the issue still occurs on the active PC, normally BETA because it is the more powerful of the two.

To describe this network, ALPHA is a Windows 7 32bit laptop, and BETA is a 64bit Windows 10 desktop. Both PCs are connected to the internet via a Netgear DC834GV3 router connected to my ISP.

ALPHA has LAN network address 192.168.0.3, and BETA is 192.168.0.2. The router is 192.168.0.1. A simple network map is displayed below:




Both PCs are getting on a bit but are still fully working. The PCs and router are powered off usually and the cables disconnected from the mains, but the messages still occur with the router left on but the PCs switched off.

Thanks

Mr Morgan.

It seems the DHCP server function on your NetGear router is not working properly, unless there's some router
setting that requires it to act as it does. You'd best get into the router admin pages and check for that. If there's
no explanation to be had there, you could just disable the DHCP function entirely, and set up the router and your
computers to use a fixed IP.

I myself used to have a very similar NetGear router, and its DHCP function was similarly borked, i.e. it would
never renew an IP lease.There were no settings
whatever in the router management that concerned its DHCP function, other than to turn it on or off.

Having a DHCP renewal request denied should not affect the internet connectivity of any client, except perhaps very
very briefly when the machine finally has to request that a new IP lease be assigned.

Incidentally, none of this has anything to do with your ISP.

Thanks to the respondents.

As the router is acting as DHCP server, I need to check with my ISP and to see if they suggest static IP addresses as an alternative to the current dynamic renewal that occurs every so often.

As for the switch, this must be logical somewhere on the network because there is no obvious hardware for it.

I will post more details here as and when.

Mr Morgan said:

As the router is acting as DHCP server, I need to check with my ISP and to see if they suggest static IP addresses as an alternative to the current dynamic renewal that occurs every so often.

The router - in its capacity as a DHCP server - is providing internal IP addresses, for use on your LAN. The question around whether a static internal IP address is an alternative isn't really one for the ISP - they have no bearing or governance/authority on how you choose to assign devices IP addresses within your network. In my experience with ISPs here in the UK, they'll most likely tell you not to change it - or just not know what you are referring to.

The ISP provides a public-facing IP address, which is likely dynamic, but this has nothing to do with the internal IP addresses. That IP address is used by a device to identify itself to other devices on the network - including the router itself. The router then sends that devices requests out to the internet via the gateway.

Basically: save yourself the hassle of contacting your ISP and try and set the IP addresses for those devices manually. If you're unsure on which settings to use, do a quick "ipconfig /all" via CMD, make a note of the IPv4 address, Subnet Mask, Default Gateway and DNS Servers and then use those to manually input the settings as necessary.

You say you don't have a switch so are the cables plugged directly into the router from the PC's do you have a router or a modem and actual switch make and model

The network map produced by Windows 7 shows a switch. This switch, if it exists, has no hardware of its own. The network Ethernet cables run directly from the PCs to the router.

Buy a new one, with upgraded modern specs, that must be something like 12 years old.
It's DHCPNACKered.

Your internal network addresses are nothing to do with your ISP.
The supposed separate switch would be in the Gateway.

Whilst you maybe able to fiddle about with static Network addresses. Your efforts would be better spent on researching new kit.

2-3 years ago I replaced a similar Linksys Gateway practically identical to that Netgear, remember it was a consideration at the time.

"It's DHCPNACKered." I like that!-)

Have you any suggestions for a replacement router?