Discussion stats
  • 3 replies
  • 2159 views
  • 0 kudos
  • 2 in conversation
Announcements

Top Contributors
Reply
Highlighted
Aspirant

R6800 Changing DHCP default gateway

My home network (desired set up):
- I have an old ISP-provided router (call it "router 1") connecting to the internet, and I don't want it to do anything other than routing to/from the internet. It's an old D-Link 3680 ADSL router that doesn't seem to have a bridge mode or similar. I have disabled wifi and DHCP, it only connects to the R6800 on its LAN port. It has a static LAN address: 192.168.1.2.
- R6800 with wifi and DHCP enabled. All my devices (wired and wireless) connect to this. Address: 192.168.1.1, DHCP range 192.168.1.3 to *.254.
- I want to connect router 1 to R6800 on a LAN socket, *NOT* the yellow WAN port. Reason: I want there to be only one local subnet behind my ISP (router 1 and R6800 both on 192.168.1.*). Connecting the two devices on the WAN socket and letting the autoconfig do its work always results in R6800 creating its own subnet on 10.0.0.*.
- Problem: if I understand correctly, this would require the DHCP service on R6800 to hand out 192.168.1.2 (i.e. router 1) as the default gateway and DNS to my devices, but these seem to be hardcoded to R6800 itself and whatever's on the other end of the WAN port, respectively.
- (Setting R6800 into AP mode won't do, as this also requires connection to router 1 on the WAN port and results in an extra subnet.)
- Question: is there any way to fine-tune these DHCP settings on R6800 so that router 1 is the only router on my network, but R6800 is the DHCP server?
Model: R6800|Nighthawk AC1900 Smart WiFi Router
Message 1 of 4

Accepted Solutions
Highlighted
Sensei

Re: R6800 Changing DHCP default gateway

> [...] D-Link 3680 ADSL router that doesn't seem to have a bridge mode
> or similar. [...]

   Ok, if you say so.

> I have disabled wifi and DHCP, it only connects to the R6800 on its LAN
> port. It has a static LAN address: 192.168.1.2.
> - R6800 with wifi and DHCP enabled. All my devices (wired and wireless)
> connect to this. Address: 192.168.1.1, DHCP range 192.168.1.3 to *.254.

   Why not use the DHCP server on this D-Link 3680?  (And address ".1"?)
Similarly, why use the DHCP server on the R6800?

> - (Setting R6800 into AP mode won't do, as this also requires
> connection to router 1 on the WAN port and results in an extra subnet.)

   No.  With the R6800 in AP mode, you would have the one subnet
(determined by the D-Link 3680, which would need to provide the DHCP
server).  That's what AP mode does.

> - Question: is there any way to fine-tune these DHCP settings on R6800
> so that router 1 is the only router on my network, but R6800 is the DHCP
> server?

   Generally, no.  Not with the normal user interface on the R6800.

   You seem to be working very hard to do something which should be
pretty easy.  Put the D-Link 3680 back to its default configuration.
Disable its wireless stuff if you want.  (But why?)  Configure the R6800
as a wireless access point (ADVANCED > Advanced Setup > Wireless Access
Point.)

   My usual advice is to shrink the DHCP pool on the main router, and
assign a static, non-pool IP address to the access point ("Use fixed IP
Address (not recommended)."), so that it's easy to find the WAP.  For
example, DHCP pool: ".2" - ".199", WAP IP address: ".200" or ".250".
(Something memorable, outside the pool.)

View solution in original post

Message 2 of 4

All Replies
Highlighted
Sensei

Re: R6800 Changing DHCP default gateway

> [...] D-Link 3680 ADSL router that doesn't seem to have a bridge mode
> or similar. [...]

   Ok, if you say so.

> I have disabled wifi and DHCP, it only connects to the R6800 on its LAN
> port. It has a static LAN address: 192.168.1.2.
> - R6800 with wifi and DHCP enabled. All my devices (wired and wireless)
> connect to this. Address: 192.168.1.1, DHCP range 192.168.1.3 to *.254.

   Why not use the DHCP server on this D-Link 3680?  (And address ".1"?)
Similarly, why use the DHCP server on the R6800?

> - (Setting R6800 into AP mode won't do, as this also requires
> connection to router 1 on the WAN port and results in an extra subnet.)

   No.  With the R6800 in AP mode, you would have the one subnet
(determined by the D-Link 3680, which would need to provide the DHCP
server).  That's what AP mode does.

> - Question: is there any way to fine-tune these DHCP settings on R6800
> so that router 1 is the only router on my network, but R6800 is the DHCP
> server?

   Generally, no.  Not with the normal user interface on the R6800.

   You seem to be working very hard to do something which should be
pretty easy.  Put the D-Link 3680 back to its default configuration.
Disable its wireless stuff if you want.  (But why?)  Configure the R6800
as a wireless access point (ADVANCED > Advanced Setup > Wireless Access
Point.)

   My usual advice is to shrink the DHCP pool on the main router, and
assign a static, non-pool IP address to the access point ("Use fixed IP
Address (not recommended)."), so that it's easy to find the WAP.  For
example, DHCP pool: ".2" - ".199", WAP IP address: ".200" or ".250".
(Something memorable, outside the pool.)

View solution in original post

Message 2 of 4
Highlighted
Aspirant

Re: R6800 Changing DHCP default gateway

Thanks for your answer.

Yes, I think it should be a fairly standard set-up, and I followed your advice and put my R6800 into AP mode with a static IP outside the DHCP pool - which is pretty close to the setup that I have in mind, except that the R6800 is not the DHCP server, but that's fine (originally I wanted to move all networking jobs from the old D-Link to the shiny new R6800, but I guess it doesn't really matter who handles DHCP).

Works like a charm now.

 

The important point is that I needed to connect the existing router on one of the 4 LAN ports, whereas the AP set up instructions on the R6800 admin interface explicitly asked me to connect it to the yellow WAN port. The first time I did just that, and the R6800 created its own subnet - with the result that e.g. my smartphone wasn't able to obtain an IP address when connected to the R6800 Wifi.

Message 3 of 4
Highlighted
Sensei

Re: R6800 Changing DHCP default gateway

> The important point is that I needed to connect the existing router on
> one of the 4 LAN ports, whereas the AP set up instructions on the R6800
> admin interface explicitly asked me to connect it to the yellow WAN
> port. The first time I did just that, and the R6800 created its own
> subnet - with the result that e.g. my smartphone wasn't able to obtain
> an IP address when connected to the R6800 Wifi.

   That should not happen _if_ the R6800 is in AP mode.  That's one of
the two primary goals of AP mode.  (The other is disabling the DHCP
server.)  I've never actually touched an R6800, so I know nothing, and
we are talking about Netgear router firmware, so many problems are
possible, but, in AP mode, it should work properly using the WAN port to
connect to (a LAN port on) the main router.

   I'd try the WAN port again.  I might also try resetting the R6800,
and then, with nothing connected to it except a computer on one of its
LAN ports, putting it (back) into AP mode.  And _then_ connecting the
WAN port to the main router.

   If the R6800 really is (cleanly) set to AP mode, and it misbehaves
when the WAN port is used, then its firmware version might be
interesting, and trying other versions might be interesting, too.  If
you have the ambition, and time to kill.

Message 4 of 4