I have four devices on my network. Two wired - a desktop and playstation 3 - and two wireless in the form of two laptops. On the two laptops, routinely (every other day) the person who uses the laptops complains that they cannot get connected to the network and that it says that they cannot acquire an IP address. To TRY to resolve this, I reserved them an IP address on the network through the router settings. This did not do anything.

How can I get this issue resolved? It's extremely tiresome to have to daily restart the router and modem in order to fix the problem until the next time it pops up.

The next time they get the problem, I suggested they ipconfig /renew. They haven't had the problem since yesterday, so I do not know the results of this yet.

Pertinent information:

The laptops are never out of range of the router.

I have a D-link router.

The wired devices never have problems.

Thank you in advance.DrSatanDracula,

Errors like "unable to acquire an IP" are DHCP lease issues (dynamic IP assignment). The DHCP protocol will try to "renew" a lease at 1/2 the lease duration. As the DHCP SERVER is the same for the wired and wireless computers, that would hint that the DHCP server is working OK (although still a possibility).

Was the reserved IP in the router a "static DHCP lease" by MAC address, or did you setup a static IP on the laptops?

I'm curious about the restoration procedure for your issue. Are you having to reset the router to get them back online? Power cycle the modem? Restart the laptop? Exact process. If you are resetting the router to restore the Wifi signal, it almost sounds like a issue with the router's radio.

I'm interested to know the following:
1) DHCP Lease Reset outcome ("ipconfig /release" & "ipconfig /renew")
2) DHCP Lease length in the routers config (24 hrs?)
3) If the Access Point's SSID is still detected by the laptops when the issue is occurring
4) What the signal strength to the router is during an occurrence
5) If the reservation was a DHCP MAC to IP Binding
6) If a static IP assignment (an IP OUTSIDE your DHCP pool's range) on the laptop helps
7) If when in a static IP configuration, whether or not you can ping your router's IP during an occurrence

Thanks! Quote from: wyatt on May 15, 2010, 06:06:16 PM

DrSatanDracula,

Errors like "unable to acquire an IP" are DHCP lease issues (dynamic IP assignment). The DHCP protocol will try to "renew" a lease at 1/2 the lease duration. As the DHCP server is the same for the wired and wireless computers, that would hint that the DHCP server is working OK (although still a possibility).

Was the reserved IP in the router a "static DHCP lease" by MAC address, or did you setup a static IP on the laptops?

I'm curious about the restoration procedure for your issue. Are you having to reset the router to get them back online? Power cycle the modem? Restart the laptop? Exact process. If you are resetting the router to restore the Wifi signal, it almost sounds like a issue with the router's radio.

1) DHCP Lease Reset outcome ("ipconfig /release" & "ipconfig /renew")

2) DHCP Lease length in the routers config (24 hrs?)

3) If the Access Point's SSID is still detected by the laptops when the issue is occurring

4) What the signal strength to the router is during an occurrence

5) If the reservation was a DHCP MAC to IP Binding

6) If a static IP assignment (an IP outside your DHCP pool's range) on the laptop helps

7) If when in a static IP configuration, whether or not you can ping your router's IP during an occurrence

So you've already replaced the router once before? Can you just try resetting 1 device to try and determine the culprit? You might be able to avoid the modem reset by using a router's re-authentication/dhcp-lease-renewal features in the web interface.

Determine Current IP Subnet

Use "ipconfig /all" in a Command Prompt to determine the following:

1) You subnet mask (ex: "255.255.255.0")
2) Your Gateway IP Address ("192.168.0.1")
3) Your DNS Server IPs
4) Your current IP address (ex: "192.168.0.100")

Get into your router and find out what your pool's range is (ex "192.168.0.2 > 192.168.0.102" )

Most home routers use a 255.255.255.0 (aka "Class-full Class C", "Classless" 24 bits or /24 - CIDR) subnet mask which allows for up to 254 hosts in "4th octet" (4th Octet = last number/4th position in the IP address "192.168.1.XXX").

The info found tells us this about your network:

Subnet = 192.168.0.0 / 255.255.255.0
Usable = 192.168.0.1 through 192.168.0.254

IP Assignments:
192.168.0.0 = Network IP - Unusable
192.168.0.1 = Router
192.168.0.2 = DHCP Pool
[...]
192.168.0.102 = DHCP Pool
192.168.0.103 = Unused
[...]
192.168.0.254 = Unused
192.168.0.255 = Broadcast - Unusable


Create your own little notes, and pick an IP address out of the Unused space.

Here are several guides for different OS's for static IP setup:
http://portforward.com/networking/staticip.htm


Once applied. Make sure you can do this in a command prompt:

1) run "ping 192.168.0.1" where the IP is your router's IP address
2) Perform DNS Checks with "nslookup www.google.com"
3) traceroute out into the Internet "tracert www.google.com"