Posted: Tue Sep 17, 2019 22:45 Post subject: Setting up Netgear Nighthawk MR1100 as a modem
I've been a DD-WRT user for years but generally set it up and leave it until something breaks. As a result, I would say I'm basically a novice at setting things up. My last setup was a Frontier DSL modem connected to a Linksys WRT54G and it worked basically perfectly for years. I had an extra WRT54G by my TV to act as a repeater and the whole house and surrounding property were covered with signal. Something went south recently and as well as my DSL really becoming unusable in 2019 (1.5Mbps is not acceptable anymore).
I just switched to using a Netgear Nighthawk MR1100 for my internet and it works fine as a router. However, I want to connect it to my wired network to. I have 2 choices afaik. I can either connect the MR1100 to a switch (already have and could do this easily) and let the device replace my routers or I can set it up to IP Passthrough mode (basically a modem) and keep using my routers.
I have been working on the DD-WRT setup for hours today off and on, and I'm not getting anywhere. I have the router showing the MR1100's IP address but no internet. If I switch the cable to my laptop, I can connect right away. I'm missing a setting of some kind and not finding any documentation so far that leads me to a solution. Any suggestions would be great!
My configuration is:
Linksys WRT54G v2.2
DD-WRT v23 (I have the new firmware, but was holding off updating pending suggestions)
Netgear Nighthawk MR1100 w/ current firmware as of 9/17/2019
EDIT: I've also tried a spare Buffalo WRH-G54S with the same results, so I don't *think* the problem is the router.
I did have a conflict with the IPat one point due to both being on 192.168.1.1. I changed the MR1100 to 192.168.2.1 and that made a difference. It still didn't work, but it felt closer.
This is on the AT&T network, so not sure if they have an issue with using the device with a router. I can ask the store who helped set it up, but not sure they are techie enough. Worth an ask I suppose. I have not looked at TTL before, so not sure what that is, but I'll Google it to see. I read a few threads on the Netgear forum indicating this configuration should work, but I dont recall what network they were on or if they even mentioned it.
It is possible that there could be a TTL issue, but after doing a bit more reading on the netgear forum, it may also be a double NAT issue. The public IP I am seeing on the MR1100 is 10.x.x.x which was a bit confusing initially. Apparently AT&T may be using CGNAT which is apparently problematic.
I'm continuing to read up on this, but any other input would be appreciated.
Joined: 18 Mar 2014 Posts: 12837 Location: Netherlands
Posted: Wed Sep 18, 2019 7:21 Post subject:
bkenobi69 wrote:
It is possible that there could be a TTL issue, but after doing a bit more reading on the netgear forum, it may also be a double NAT issue. The public IP I am seeing on the MR1100 is 10.x.x.x which was a bit confusing initially. Apparently AT&T may be using CGNAT which is apparently problematic.
I'm continuing to read up on this, but any other input would be appreciated.
Double NAT or Carrier Grade NAT should not be an issue as long as the IP addresses of the router and LTE modem/Router are different.
The problem can be TTL related depending on carrier they do not allow to hook up a router to the carriers LTE/hotspot.
Hooking up a router (with NAT) decreases the TTL and that is how the carrier detects a router is hookep up.
I figured the issue could be the quote symbol si I did try other versions. I'll try your command and report back.
The router is running a pretty old version of dd-wrt and not sure about the size. I just used the default download at the time so I might be able to use a larger one.
I ran your command and am still getting an error for some reason. FWIW, I ran this on the web gui this time so perhaps there could be a difference with telnet/ssh? I had the same issue last time I tried with either so I'll have to try again later I guess (late for work).
Warning: wierd character in interface `-j' (No aliases, :, ! or *).
Bad argument `TTL'
Obviously it doesn't like the "TTL" string for some reason. I downloaded the newest firmware I can find for this router and will update in case, as you said before, there was a limitation due to the firmware I had installed.
I updated the firmware on the Buffalo to v24 standard. After update, I was able to run the command to set the TTL to 64. I ran the check and saw the following output:
Code:
Chain PREROUTING (policy ACCEPT 2131 packets, 497K bytes)
pkts bytes target prot opt in out source destination
Chain INPUT (policy ACCEPT 1474 packets, 120K bytes)
pkts bytes target prot opt in out source destination
Chain FORWARD (policy ACCEPT 901 packets, 535K bytes)
pkts bytes target prot opt in out source destination
Chain OUTPUT (policy ACCEPT 1915 packets, 1913K bytes)
pkts bytes target prot opt in out source destination
Chain POSTROUTING (policy ACCEPT 2832 packets, 2450K bytes)
pkts bytes target prot opt in out source destination
26 11043 TTL 0 -- * vlan1 0.0.0.0/0 0.0.0.0/0 TTL set to 64
So, the command took.
After running that, the Nighthawk immediately started working. I do need to get this working on my Linksys router as that is intended to be the installed setup (Buffalo was just a test).
Joined: 18 Mar 2014 Posts: 12837 Location: Netherlands
Posted: Fri Sep 20, 2019 8:11 Post subject:
Great you got it solved.
Regarding a proper build for your 54G, you have to google for it there are build threads regarding this subject, I would be hesitant to use the latest builds.
From my memory 14929 was a good (but old) starting point)
I have used 27858 in the past for my 54 GS but that one is in storage at the moment.
I found a suggestion to use a variant of the firmware I used on the Buffalo. Iirc, it was v24 mini for wrt54g. In any case, after following the same steps, I was able to get everything working on that router as well.
That said, speed tests show that wifi speeds are restricting my connection speed. When wifi, I see between 5-15mbps down whereas wired is up to 30mbps. So, I will have to find a new router. Is there a suggested model for use with dd-wrt that is budget friendly? I've seen routers can cost over $5000USD these days!
Joined: 18 Mar 2014 Posts: 12837 Location: Netherlands
Posted: Fri Sep 20, 2019 16:37 Post subject:
In Europe value wise the Netgear R6400 v2 is about E 90,
I have installed a bunch of them, working well with DDWRT, throughput wise about 700 Mb/s with SFE LAN<>WAN and with OVPN about 35 Mb/s.
A step up is the Netgear R7800, which is actually the best value for money but will set you back E 160
My personal favourite is the R7800 which will get you about 850 Mb/s LAN<>WAN and I get about 90 Mb/s on OVPN but I have seen faster reported.