DHCP not working for some clients

[Richard Adams]

Firmware is 1.4.7

DHCP is working for some hosts, while not for others, but works for all hosts with a non-gargoyle router.

Generally, DHCP is method used by some hosts to get an IP address from the router.

Not working:
Droid phone on wifi connection. Droid is connected through an engenius wireless bridge that plugs into switch which plugs into the TP-Link WR741D gargoyle router that was purchased from the Gargoyle store.

Wilife security camera software. This one is unusal since there a 4 powerline LAN cameras operated through software on a windows PC. The DHCP requests for each camera only occur when the software runs.

In both of the above cases, If I turn off the DHCP in the gargoyle router, and then enable DHCP in another router that is plugged into the switch, with no topology or wiring changes, both of the above are able to get an IP address from that other router. I am only connected to one LAN port on that router and there is no wireless on it, so there is no DNS info given by the DHCP fulfillment. The other router simply proves that the DHCP packets are moving to the gargoyle, but are not fulfilled. I have upnp turned off on the gargoyle and the other router.

On the gargoyle router I have already tried using a static IP assignment, and also tried turning upnp on, which did not help. While this DHCP issue is going on, other hosts are able to operate DHCP with the gargoyle router, including a magic jack+ with a gargoyle static assignment, and a windows PC with no gargoyle static IP assignment.

Conclusion: some DHCP requests are not being fulfilled by the gargoyle router.

Is this a known issue or is the router I bought from gargoyle store defective?

[pbix]

There are no known issues with DHCP in Gargoyle.

As to your conclusion you state that some clients can work and some cannot. So I conclude that no conclusion can be made as to what the problem might be.

Remove the switch and see of the Droid can connect with the WR741D Wifi directly. My son has a Droid and has no problems connecting.

[Richard Adams]

Can't try the droid yet since it is in use by my son's. I set a static IP on it and that worked.

I plugged my PS3 directly into the gargoyle and it could NOT get an IP address with DHCP, while static setting an IP address on the PS3 menu worked. The failure of the gargoyle to assign the PS3 an IP on a directly wired connection surely is an indication that something is not right. The PS3 has worked ok for years with 4 other routers, and DHCP still works with these other routers.

The Magic Jack+ and Windows XP computer that use DHCP work okay getting an IP address from the Gargoyle.

Before using the Gargoyle, I set the gargoyle's host name and wan mac address to match my prior router, thinking that my cable modem would not change my WAN IP address. The WAN IP changed anyway, so there is other info I could not match that the cable modem detected.

Maybe there is an issue with the mac address or host name being changed in the gargoyle that affects DHCP.

Also, one other thing I noticed is that the IP address that gets assigned does not start at the beginning of range selected. For example, I select the range to start at 70, and yet the first address that the Gargoyle assigned to the PC was 73. I wonder if there may have been some "fail and retry" attempts going on, that wound up skipping over 70, 71 and 72. Is skipping like this normal for the gargoyle?

[pbix]

The failure of the gargoyle to assign the PS3 an IP on a directly wired connection surely is an indication that something is not right.

This much I can agree with.

Before using the Gargoyle, I set the gargoyle's host name and wan mac address to match my prior router, thinking that my cable modem would not change my WAN IP address.

The first approach I use to learn about such problems is to simplify. I would reset all the router settings to default and then try. A WAN connection is not needed for DHCP to work properly. With all default settings all your devices should get assigned into the 192.168.1.x subnet. Does this work? Post your status->overview and connected hosts pages in this condition.

Also, one other thing I noticed is that the IP address that gets assigned does not start at the beginning of range selected. For example, I select the range to start at 70, and yet the first address that the Gargoyle assigned to the PC was 73. I wonder if there may have been some "fail and retry" attempts going on, that wound up skipping over 70, 71 and 72. Is skipping like this normal for the gargoyle?

This is normal DHCP behavior and not an indication of a problem.

Learn how to log onto your router using putty. Then type 'logread' from the command line and you can see any log message that dnsmasq is writing relative to DHCP. There may be a clue there.

Finally study DHCP and use Wireshark on you PC to observe the DHCP traffic on your network.

These are the approaches I recommend to you.

[Richard Adams]

Thank you kindly for the very helpful suggestions which I will follow.