[Closed] IT / networking cluelessness - what am I doing wrong?

Is the BT WiFi thing trying to do dhcp? If so, you'll have 2 dhcp servers on the same network, which will cause all sorts of issues.

What 5G modem are you using?

Why are you using a 5g modem, router and BT WiFi (prob modem router) all at the same time?

Without knowing exact hardware based on above description after my quick skim read you could unintentionally potentially have 3x modem routers all interfering with eachother.

If you don’t know the exact hardware take a pic and post. Sure it will get sorted quickly enough.

Thanks Ta11Pau1 and sillysilly.

The hardware is as follows:

5G Huawei CPE Win router - which has (very poor) instructions stating it should be connected to the WAN port of another router.

(Connected to)

Huawei CPE Pro router

(Connected to)

BT whole home Wi-Fi system

The Bt kit doesn’t do DHCP but both huawei routers support bridge mode. I’ve tried enabling bridge mode on the 5G router and if I connect my laptop to the CPE pro router by Ethernet it works fine.

If I take that same Ethernet cable from the CPE pro router and connect it to the BT network the latter doesn’t seem to “see” the internet.

Which of the routers should be used for creating addresses on the internal network / which one if any should have bridge mode turned on?

If the WiFi device can get to the modem or router settings page then it's not likely to be dhcp as it wouldn't see them if it had a 169.254 address or was on a different subnet.

Might be DNS? It always DNS...

On the same device, connected to working ethernet and again to Wi-Fi, open command prompt and type

Nslookup

Then press enter. This should give you an idea if the BT WiFi or the huawei router/modem is providing dns.

Essentially, you want one router, which has your modem plugged into the WAN port and does DHCP etc, and everything else plugging into that as a client or bridge.

Two things that could cause described issue - BT home WiFi linked into router with it's WAN port - don't do that, use a LAN port, or BT home WiFi doesn't like working as a Bridge.

OK, I've done a bit more fiddling and may have narrowed the problem down a bit.

I've tried to connect a different Wifi mesh system (a Tenda MW03) to the 5G Router and the new mesh system doesn't won't either - so that's two mesh systems that don't work.

I've tested the mesh system with the 5G router set to "normal" mode and "bridge" mode and in both use cases the mesh system doesn't see the network connection. Again, if I take the cable that's connected to the mesh system and put it in the ethernet port of my laptop I can access the internet.

Do I need to turn DHCP off on the 5G router or something else? Completely confused by this but the semi good news is that the 5G router is easily doing 300Mbps downloads and that even before I've put it up on the roof...

If it’s working for internal addresses, but not external it sounds like a routing problem, rather than DHCP or similar.

If the BT device has a modem, it probably expects to send external ‘internet’ traffic via that modem. What you should try is configuring the default route (i.e. 0.0.0.0/0 assuming no IPv6) on the BT router to use the Ethernet port or IP address the 5G modem is connected to. Depending on the BT configuration, the Huawei modem may need to be in bridged or route mode.

Run ping / tracert against names / IP addresses to find out where the problem is.

Random guess, have two of your devices got the same fixed IP address (192.168.0.1 or similar)?

set the modem to not use DHCP and NAT: it should just act as a modem and provide an internet connection to the WAN port of the BT primary MESH router.

The MESH system should provide DHCP and NAT.

check your modem IP address and router LAN IP address range. The modem’s IP address should be OK but it keeps things simple if it is not in the MESH LAN range.

aside from the 5G external connection your set up sounds similar to my Virgin superhub 4 to ASUS MESH set up

Why do you need a router as well as the mesh? The latter acts as a router itself.

Try it without the router and the 5g should be outside the LAN IP address range.

Check that the IP address of the 5g LAN port is where the mesh is sending external traffic (i.e. it's WAN port should be on the same subnet).
So:
Mesh LAN range 192.168.1.X
Mesh WAN port 10.0.0.2
5g LAN port 10.0.0.1

(All the above are examples but hopefully give you an idea)

Thanks Pretty Green Parrot and sharkbait!

I'll try turning off DHCP on the 5G router and see what happens then. The BT Mesh Wifi doesn't itself do DHCP so does that mean I still need a proper router in the middle of the 5G router and the Mesh? Rather confusingly the Huawei instructions (limited as they are) refer to the "outdoor router" and the "indoor router" hence setting it up that way to begin with.

On the 5G router I've taken screenshots of the management console. I tried to add the Nova mesh with a dedicated IP address but on the Nova kit it requires me to enter the subnet etc and I literally have no idea how to find that..

https://imgur.com/sljKD7s

https://imgur.com/3x0ZhFU

https://imgur.com/8SK3ioy

So it seems the BT system isn't a router!
If it's just an access point then try manually setting the IP address of a laptop with 192.168.118.1 being the gateway address and see what happens.

And check what the firewall settings are - is set it to allow all internal traffic out initially.
Adding mac filtering at this stage may complicate matters.

Sorry to jump in. But lets get the basics first, it will help anyone trying to resolve this.

Set everything up as you want it, 5g - router - bt wifi

then from a command prompt on your laptop type ipconfig /all

post the results for your wifi lan adaptor here.

Then we know where your laptop is getting its dhcp from, what is the default gateway, and dns etc.

Was about to say what trailwagger said: ipconfig /all

It'd also be useful to have the results of ipconfig /all when it's connected so that it works (i.e. modem - router - laptop)

In the image of the MAC filter settings you have it set as "Allow" with only one MAC address in the list. My understanding is that the filter should either be set to "Block" with no items in the list or "Allow" with the MAC address of all the devices listed.
Allow - Allow only items in the list and block all others
Block - Block items in the list an Allow all others
If you can turn MAC filtering off I would try that.

OK, a further update from the House of Clueless. I've turned off Mac filtering and DHCP on the 5G router and have done a series of tests - changing each variable in turn and hopefully capturing the info requested above.

I've managed to get to the point where DHCP is turned off on the external WAN facing device but is turned on for the internal LAN facing device. I can access the internet using an ethernet cable to the internal device but when I try and connect either of the mesh systems they don't seem to see the internet connection even though my laptop does.

Thanks to everyone who has helped so far!

In case it makes a difference, the laptop I'm using is a Mac.

TEST ONE – LAPTOP CONNECTED DIRECTLY TO 5G ROUTER BY ETHERNET

5G Router configuration:
 Mac filtering = disabled
 DHCP - enabled

Network Information on laptop – direct connection to 5G router by ethernet:
 LAN IP Address: 192.168.118.1
 IP address: 192.168.118.105
 Subnet: 255.255.255.0
 Router: 192.168.118.1
 DNS Server: 192.168.118.1

Test result: laptop could connect to the internet

TEST TWO – LAPTOP CONNECTED TO CPE PRO ROUTER BY WIFI - CPE PRO ROUTER CONNECTED TO 5G ROUTER VIA ETHERNET USING WAN PORT

5G Router configuration:
 Mac filtering = disabled
 DHCP enabled.

When DHCP is disabled on the 5G router it generates the message “After shutting down the DHCP server, your router will no longer automatically assign IP addresses to network devices. To access the Internet, you must manually enter the IP address on the network device.”

CPE Pro router: DHCP enabled – laptop connected to CPE router by Wifi

Network Information on laptop – direct connection to 5G router by ethernet:
 LAN IP Address: 192.168.8.101
 IP address: 192.168.8.101
 Subnet: 255.255.255.0
 Router: 192.168.8.1
 DNS Server: 192.168.8.1

Test result: laptop could connect to the internet

TEST THREE – LAPTOP CONNECTED TO CPE PRO ROUTER BY ETHERNET - CPE PRO ROUTER CONNECTED TO 5G ROUTER VIA ETHERNET USING WAN PORT

5G Router configuration:
 Mac filtering = disabled
 DHCP enabled (couldn’t get it to work with DHCP disabled)

CPE Pro router: DHCP enabled – laptop connected to CPE router by Wifi

Network Information on laptop – direct connection to 5G router by ethernet:
 LAN IP Address: 192.168.8.102
 IP address: 192.168.8.102
 Subnet: 255.255.255.0
 Router: 192.168.8.1
 DNS Server: 192.168.8.1

Test result: laptop could connect to the internet

TEST FOUR – MESH SYSTEM CONNECTED TO CPE PRO ROUTER BY ETHERNET - CPE PRO ROUTER CONNECTED TO 5G ROUTER VIA ETHERNET USING WAN PORT

5G Router configuration:
 Mac filtering = disabled
 DHCP enabled (couldn’t get it to work with DHCP disabled)

CPE Pro router: DHCP enabled – mesh network connected to CPE router by same ethernet cable used for laptop

 No connection possible via DHCP
 Tried to configure using static IP but don’t know what to put for the
o IP Address – ?
o Subnet Mask – ?
o Default Gateway – ?
o Primary DNS server – ?

Test result: mesh system could NOT see ip address / connect to internet

Ok, so both the 5g router and the router are doing DHCP, but that doesn't matter as the router takes over that role and provides IPs in the 192.168.8.xxx range. Which works as the laptop can access the internet externally.

Issue is the laptop isn't getting an IP when connecting via the mesh wifi.

This thread may give an idea as to why - https://community.bt.com/t5/BT-Devices/BT-Whole-Home-Premium-Wifi-Now-here-s-why-it-doesn-t-work-for-me/td-p/2012000

The premium wifi seems to hijack your DHCP and default gateway in a way I've never seen before. Any device connecting to the disc was issued with an IP address seemingly coming from the main router, but the default gateway was the address of the disc, e.g if my disc had obtained IP address 192.168.1.123 from the router, any device connecting to the disc would obtain a default gateway 192.168.1.123 rather than the normal router address in this case 192.168.1.1.

You want to check what IP the mac has, open terminal and type ifconfig and press enter.

If the BT wifi has an IP of 192.168.8.1xx (should be visible on the Pro router) and the above is true, then your mac default gateway will be set to the same. This will be the issue, as the default gateway should be set to 192.168.8.1, which is also your DHCP server, and if the laptop can't see the DHCP server, it can't be assigned an IP address and can't access anything.

Try giving your laptop manual settings (on the device) of:

IP: 192.168.8.102
subnet mask: 255.255.255.0
default gateway: 192.168.8.1
Primary DNS server: 192.168.8.1

Does the BT box have multiple ethernet ports? If so, what happens if you connect your laptop to one of those?

It looks like the BT box is either filtering DHCP packets, or isn't bridging the wired connection to wireless at all. Trying a static address as above should tell you which one.

Ya to all the above but why the needlessly complex setup? Are you trying to wire up Buckingham Palace on a budget? 😂😂

Sounds lime you need a Unify Dream Machine and maybe some Unify AP’s...

Ta11Pau1 - I've set my laptop ethernet connection to the settings in your post and it works fine. On my Mac it also has settings for IPv6 which are set to "automatic" - I didn't change those because it looks like long strings of gobbledegook.

Home Whole Premium used to do DHCP but they turned it into Bridge mode in a software update in May - so it should work. But in this case a completely different Tenda set up can't seem to see the internet either.

PDW - yes - the BT wholehome has 2 ports. It has to be connected on Port 1 from the router.

SillySilly - it seems complicated but shouldn't be. The 5G router requires a separate "indoor" router based on the device manufacturers' spec sheet. Although the inside router has wifi, it's not strong enough to reach most of the rooms in the house including my home office - hence using a mesh network for wifi. I previously tried powerline wifi adapters but the wiring in the house was done by cowboys so the speeds were abysmal.

Thanks everyone for your advice so far!

Yeah don't worry about IPv6... hahaha.

So with the laptop set to those settings, can it connect to an external website when connected to the BT wifi?

Ta11Pau1 - no, can’t connect the laptop with those settings to the BT whole home (or the Tenda mesh) because neither of them seem to work with the router...

OK, so if it's not working even with the static settings, then that suggests that the BT wifi thing isn't passing packets (another explanation would be if the BT wifi thing had the same IP as your router, but that seems less likely given that the router is using 192.168.8.0 as its network).

Is the BT wifi thing definitely in bridge/access point mode, rather than router mode?

What happens if you connect the router to the other port on the BT wifi box?

Pdw - the bt mesh still doesn’t work even when connected using the other port.

Which of the following two technical solutions is most likely to resolve the problem?

1. Buy a new router
2. Smash the whole lot into pieces with a hammer

Have you disabled Huawei's own WiFi on the CPE Win and set the routers so that you don't end in a multi Nat situation?

Also worth giving Huawei a call directly and seeing if they can take you through on phone based on your setup.

Hi silly silly,

Yes - the WiFi on the CPE devices is disabled. I've also tried calling Huawei but they literally do no support on their own products. Every time I've called I get told they need to speak to someone with more knowledge and they'll call back but they never do. They also don't provide any proper product documentation which doesn't help...

Which of the following two technical solutions is most likely to resolve the problem?

1. Buy a new router
2. Smash the whole lot into pieces with a hammer

I'd probably try to find a mesh wifi router that can replace both the CPE router and the BT thing. The fact that you can plug your laptop into the modem and it just works suggests that the modem is presenting the connection as simple IP with DHCP, so any router that can do DHCP on its WAN port should work.

It's probably worth trying the Tenda thing again. It looks like it should have 4 settings for the internet connection (PPPoE, DHCP, Static IP, Bridge). I'd expect it to work if you plug it into your *modem* and set it to DHCP, or plug it into your *router* and set it to bridge.

It doesn't really surprise me that the BT thing can't be made to work. Years ago I tried to use a BT home hub (ADSL modem/router) as a simple wifi access point, and it didn't seem to be possible. As per tallpaul's link above, BT seem to enjoy meddling and restricting stuff so that it only works in their ecosystem, rather than providing generic kit that can be reused.

What's the point of the CPE router? Can't you plug the Mesh straight into the modem?

So I've looked at your earlier post as it's a confusing hot mess, and attempted to map your network.

5G modem outside - public address assigned by ISP
5G modem inside - static 192.168.118.1, serving DHCP of 192.168.118.100 - 192.168.118.200

CPE router outside - 192.168.118.? assigned by DHCP from the modem
CPE router inside - static 192.168.8.1, serving DHCP of 192.168.8.x on both NIC and Wi-Fi

Mesh system outside - 192.168.8.? assigned by DHCP from the CPE router
Mesh system inside - Whatever its defaults are. RTFM?

We really need to shine a light onto the Mesh configuration as it seems there's various modes it can work in, but this concerns me:

No connection possible via DHCP

Are you suggesting that you're not being assigned an IP address at all when connected to the Mesh? It just times out?

For this to work, one of two things needs to be happening. Either the Mesh needs to be running a DHCP server to allocate addresses to clients, or it needs to be forwarding on requests to another DHCP server.

This seems to work in an unusual way on the BT system as per the note above - the original thread is here and maybe worth a read - but I'd expect you to be receiving something even if it's wrong / nonsense.

I think I'd be factory resetting it, then declaring it broken if it still didn't work.

(Disclaimer: I know sod all about this BT thing.)

Hi Cougar,

Thanks for trying to help me fix it. To be honest I'm way out of my depth and in the course of fiddling have now broken the bit that was working...

The bit I'm confused about is the IP addressing, subnets and gateway settings but perhaps you could help? I think the settings need to work as follows:

1. The 5G Device should have DHCP turned OFF
2. The router should have DHCP turned ON
3. The router should be set to connect to the 5G device using a static IP address. Is that correct?
4. The 5G device needs to be on the same subnet as the router. It's currently 192.168.118.1 with the router set to 192.168.8.1 - which I think means the 5G device needs to be set to 192.168.8.xx
5. Does the 5G router need to be set to "bridge" mode?

I really need someone who knows what they are doing to answer the above and help with what the rest of the settings should be. If the 5G device is set to 192.168.8.X what number should X be, and what details should I put on the router i.e.

5G Settings
IP = 192.168.8.?
Subnet= ?
DHCP Range - isn't required - is that correct if DHCP is turned off

ROUTER settings
Connection type = Static IP or Dynamic
LAN IP = 192.168.8.?
DHCP Range = 192.168.8.? to 192.168.8.?
Is the subnet setting 255.255.255.0 correct?
Do I enter google's DNS in the DNS server setting or something else i.e. 8.8.8.8
Is the gateway setting the same as the IP for the 5G router IP address?

Any help would be massively appreciated!

1. The 5G Device should have DHCP turned OFF
2. The router should have DHCP turned ON
3. The router should be set to connect to the 5G device using a static IP address. Is that correct?

Turning DHCP on/off could refer to whether the device obtains an IP for itself via DHCP, or whether the device provides IPs to other devices via DHCP.

Earlier in the thread you've said that your laptop was working if you plugged it directly into the modem or the router. This suggests that the modem was providing addresses by DHCP, and that the router was getting an address for itself via DHCP.

So I don't think you need to configure static addresses, but you can probably make it work that way too.

4. The 5G device needs to be on the same subnet as the router. It’s currently 192.168.118.1 with the router set to 192.168.8.1 – which I think means the 5G device needs to be set to 192.168.8.xx

A router will be on (at least) two subnets: one for its one WAN connection, and one for its LAN connection.

From previous posts it sounds like your outer was using 192.168.8.* for on its LAN side, and handing out addresses in that range via DHCP.

It will need to be using a different subnet on the WAN side, but as above, I think it was doing that automatically previously.

5. Does the 5G router need to be set to “bridge” mode?

Basically you need one device to do routing, and any other devices to be in bridge mode.

So I think the answer is "no". You want your 5G router to be a router, and if you connect a wifi access point to it, then that should be in bridge mode.

Although as has been pointed out before, most wifi devices are capable of routing, making your 5G router redundant.

It might help if you post screenshots of that settings pages that you're looking at, as that'd make it easier to understand whether we're talking about the router getting is WAN address via DHCP vs running a DHCP server on its LAN side.

The bit I’m confused about is the IP addressing, subnets and gateway settings but perhaps you could help? I think the settings need to work as follows:

1. The 5G Device should have DHCP turned OFF
2. The router should have DHCP turned ON
3. The router should be set to connect to the 5G device using a static IP address. Is that correct?

You EITHER need a DHCP server to assign a dynamic IP address to an interface OR to disable DHCP and use a static. Wherever possible I try to avoid manually assigning addresses, it causes more problems than it solves and it's often indicative of a wider problem (in domestic configurations at least).

So yes, that configuration should work. Prior to this the 5G router was (presumably) assigning the IP address to the outside (WAN) interface of the router. So then no DHCPy no worky unless you assign a static IP address.

DCHP traffic doesn't typically cross between subnets unless explicitly instructed to do so.

You keep referring to the 5G "router." Is it a router or a modem? If it is a router then what's the point of the CPE router? What are you trying to achieve with this BT thing? It really does sound unnecessarily overcomplicated.

Thanks Cougar, that's great.

Yes - understand that normally you wouldn't use two routers but that's the way Huawei have made it - it can "route" but only to a single device at a time unless a second router is used - which thus makes it a pain to set up.

So what else are you plugging into it? Your Mesh whosit is a "single device," have you got other things you need wired Ethernet for?

Yes – understand that normally you wouldn’t use two routers but that’s the way Huawei have made it – it can “route” but only to a single device at a time unless a second router is used – which thus makes it a pain to set up.

I really don't think that's right. Your *modem* may only be able to connect to a single device. You said in your original post that you could connect your laptop directly to either the modem, or to the router. So what do you think that router is actually doing?

I think your issue is that the BT box isn't configured or can't be made to talk to either your modem or router.

Hi all, quick update...

So I ordered an amazon eero router to see if it was the Huawei router playing up - with the intention of returning it if it didn’t work. It was the only router with gigabit ports and easy set up that I could find...

The whole lot was up and running within 5 minutes of the amazon guy dumping the cardboard box on the front doorstep. The BT mesh is also working fine.

As an aside, the eero router has some nice features I noticed in the set up
- so if I didn’t already have a lot of mesh kit I would probably opt for that.

Thanks to all of you who offered help and advice along the way.

>.<