NETGEAR is aware of a growing number of phone and online scams. To learn how to stay safe click here.
Forum Discussion
Solved
RAX40 Router unable to assign a reserved IP to some devices (MACs)
Hello,
My router normally assigned IP dynamically via its dhcp server. But, in order to keep track of my devices more consistently, I decided to assign specific IP addresses to specific devices (MAC addresses). Note that by devices, I mean any node connected to my LAN or WLAN (IoT, printer, computers, stream device, etc). For some devices, whenever I try to assign a specific IP address to a given device on the router's interface/dashboard (Advanced > Setup > LAN Setup), the following error message pops up:
"Edit DHCP reservation failed!
This screen will automatically return to the previous screen in a few seconds..."
I double checked any possibility of IP conflicts, etc. No issue there.
Firmware Version V1.0.4.102_1.0.1 |
Any insights would be appreciated.
-tk3000
Salt that sequence away, "once I rebooted the router a second time..." you will use that again in the future.
You had me shaking my head when you started off a sentence with "The first hundred devices..."
It is a good idea to keep a spreadsheet with your device names, IP addresses, and MAC addresses.
Please mark this as resolved so others can benefit from the discussion.
8 Replies
Thoughts to consider:
The discussion is about IPv4 addresses, not IPv6.
Make sure your new chosen IP address is within the range you established in the LAN setup for your DHCP server. There is a range start and stop point configured in the router.
Different devices behave differently, but usually you cannot change an IP once assigned with the devices powered on and the connection made. To change that IP address, you would need to power down (pull the power cord) for the device to break the connection. Then make the changes in your router and power it down (pull the power cord). You might have to power down and restart your router before you can make the IP address assignment. When you start them back up, power up and let the router stabilize first before powering up the device.
Many devices have multiple MAC addresses. My smart TV has one for the 2.4 GHz radio, one for the 5 GHz radio, and one for the Ethernet port.
Remember too that there are different ways of assigning IP addresses to devices. You can do it on the router with Address Reservation.
On many devices you can set the IP on the device itself. I do that on NAS boxes and printers.
Which route you take depends on the device and what you have in mind.
Kitsap & michaelkenward:
Yeah, all the nodes are in the same subnet (255.255.255.0 mask for 192.168.1.0). The first hundred devices are supposed to have their IP addresses assigned by the devices themselves (static), including the router itself (192.168.1.1); so these addresses are out of the scope of the dhcp server.
The dynamically assigned IPs are leased randomly within the remaining pool of IP addresses or the router's dhcp server assign them in a reserved fashion (specific IPs to specific MACs). As of now, I am trying to set up the router so that most IPs will be assigned in a reserved fashion by the dhcp server (specific IP to specific device/MAC). So, there should be no conflict. All in all, there are three block of IP addresses: 1) static block; 2) reserved assigned by dhcp server; 3) randomly assigned by dhcp server.
I tried to to do what you suggested, turn off the power to a device connected to the network and then use its MAC address to reserve a given IP to the device on the routers interface. But whenever I try to check and look up the attached devices in the routers web interface, the device turned off seems to still be there present (I refresh the attached devices table/list to no avail).
Typically, what I do in this type of situation is a ping sweep/scan of the network (I use nmap: "nmap -sn 192.168.1.0/24" or "nmap -sP 192.168.1.0/24"). But to my surprise nmap is only returning /reporting 3 hosts/ips up, and I know that there are at least 11 nodes in my LAN/WLAN; which is really odd.
I did not power down the router though, just rebooted it. I will try to physically power it down in my next attempt.Thanks!
