[daryesh]

Hi,
 
I have the following problem with my Nighthawk X8:
 
I'm connected to internet by fibre, my connexion is:
 
ONT ISP --> R8500 --> LAN
 
I connect an ancien TP-Link Router and I get an IP address by DHCP and can connect to internet, no problem here. The only setting I need is to clone a MAC address I have from my ISP.
 
Then I connect the Nighthawk X8 and set the same parameters that above (DHCP address and MAC clone).
 
Then I cannot connect to internet. Looking all the parameters I can see that my ISP send to me 2 Gateway IP address, while the TP-LINK is able to select only the first Gateway IP address, the R8500 puts the last number of the first Gateway  and the first number of the second Gateway, that is:
 
Setting as Dynamic Address:
 
IP Address: 217.67.xxx.xxx
Subnet mask: 255.255.252.0
Default Gateway: 217.67.xxx.x 217.67.xxx.x
DHCP Server: 213.111.x.xx
 
With DNS Servers.
 
With this configuration internet doesn't work, but if I set to static address then I can see the following configuration:
 
IP Address: 217.67.xxx.xxx
Subnet mask: 255.255.252.0
Default Gateway: 217.67.xxx.x 217
DHCP Server: 213.111.x.xx
 
With DNS Servers.
 
And then I delete the last 217 from the Default Gateway(leaving it as Default Gateway: 217.67.xxx.x) and it works until my ISP renews the IP address (every two hours). How can I set the router to only use one Gateway?

I have tried official firmware and dd-wrt firmware and both do the same.

Any suggestion? If not then I would have to RMA the X8. For information an Asus RT-AC88U I had before did the same but the TP-Link Archer C7 works fine.
 
Thanks in advance.

[Per Yngve Berg]

If I have understood you correctly, you do not connect both routers simultaneously with the same MAC address. That will not work.

Have you tried to reset the R8500?

If you connect the WAN of the R8500 to a lan port of the TP-link, do you get a doubble address then to? If yes, are they still equal?

I would suspect a nvram variable error.

ssh into the router:

nvram show | grep 217.67.

[daryesh]

Hi,

"If I have understood you correctly, you do not connect both routers simultaneously with the same MAC address." --> Obviously, I connect/disconnect every device and switch off the ISP ONT every time.

"If you connect the WAN of the R8500 to a lan port of the TP-link, do you get a doubble address then to? If yes, are they still equal? " Not tested yet. I will do later and post result.

Thanks.

[daryesh]

Hi,

"If you connect the WAN of the R8500 to a lan port of the TP-link, do you get a doubble address then to? If yes, are they still equal?" --> The R8500 gets the only gateway of TP-Link (the address of the TP-Link router).

For the command nvram show | grep 217.67. I'll do the test later as actually the internet connection cannot get broken.

Thanks.

[daryesh]

Hi,

I remember that an Asus RT-AC88U had the same problem but with the stock firmware as I couldn't install DD-WRT.

Same symptoms that the Netgear with the two firmwares I tested. Could the problem come from the chipset Broadcom?

[daryesh]

Hi,

The output of the command nvram show | grep 217.67. is:
size: 51180 bytes (79892 left)
wan_gateway=217.67.156.2 217.67.156.3
wan_ipaddr=217.67.158.196

If I try to traceroutes it says: Network unreachable.

Thanks.

[Per Yngve Berg]

What did you get behind the TP-Link?

I believe this is an issue with your ISP.

[daryesh]

Hi,

Thanks for the answer. My connection is:

Connection of optic fibre my home(ONT Alcatel Lucent).

From the ONT to the TP-Link.

If the problem is from my ISP, why the TP-Link is able to work correctly?

From my point of view it is a problem how the firmware for the BROADCOM chipset manages the gateway as I posted before I had an ASUS RT-AC88U had the same problem. Look this:

I set the R8500 to get the address automatically, it gets the address but cannot browse internet (I'm aware of this), then I write down the IP address, Subnet mask, Gateways and DNS. I switch to static address and put the data I got before, when I go to the Gateway, the last octet has the format "2 (space) 217", that is, the last octet of the first gateway and the first octet of the second gateway, then I edit this last octet and delete the space and the 217, leaving it to 2 alone. Then I can browse internet until the lease time (1 hour 55 minutes), when my ISP renews the IP address as it is set to static, then internet connection drops and I have to do the same procedure again.

Another test I did:
Setting the WAN to DHCP and creating a static route to internet telling the router to use the only first gateway, it works but I think it is not well done as I see connection breaks.

Thanks again.