Issue with Technicolor CGA2121 Router: Connectivity Loss on Asus Router, Console & TV

Hello
With the new contract with Multimedia, a technicolor cga2121 modem/router was installed for me and for a few days it was ok. I have consoles, tv and a second asus router connected to it, which makes me wifi. 2 days ago the asus router lost its connection to the internet, yesterday the console and internet it is only in tv. Of course, I do not have access to the multimedia router settings and resetting the routers did nothing.

How do you have these routers connected to each other - what ports are they connected to?
What happens when you disconnect the Asus completely?

Yes, I have it connected

Added after 11 [minutes]:

With various combinations of connections, the Internet is only on the TV.

pprzybylski80 wrote:

I do not have access to the router settings from multimedia

There is access, limited but is through the customer portal.

Either Asus for the LAN port and you make an AP out of it, or you switch Technicolor to bridge mode and put all the equipment under Asus and then Asus under WAN as you have now (the second option is better).
Now you have a mish you have there and it is no wonder that some of the equipment does not work.

[img-0] So it's supposed to be connected like this? Technicolor is probably in bridge mode, because it can't run wifi. [img-0]

Added after 1 [minutes]:

You call multimedia and arrange to switch to modem mode, just ask to talk to some technician / service technician and not a chatterbox from customer service who will have no idea what you want to do.

After switching and restarting the router, you can connect your own router.

Because when I have it connected like this, there is no internet anywhere.

Bridge mode and WiFi are two separate things. You probably won't switch it to bridge mode, because Asus looks like some cheap toy that probably can't handle routing several hundred Mbps.
The Asus router must be connected to the LAN port and configured according to this guide, but the IP address of the LAN interface must be changed (NOT WAN - what everyone does) and DHCP turned off: https://www.tp-link.com/pl/support /faq/417/

However, before that, try to disconnect everything from the provider's router and connect only wired clients to it and test the operation of the services.

Added after 2 [minutes]:

pprzybylski80 wrote:

Because when I have it connected like this, there is no internet anywhere.

Because in bridge mode, your own router needs to be properly configured, not just push the conductor.

pprzybylski80 wrote:

So is it supposed to be connected?

Yes, exactly.

pprzybylski80 wrote:

Technicolor is probably in bridge mode, because it can't start wifi

MM is now part of Vectra, Vectra has changed the operation of the cable modem via the website, here is a link to MM, see:
https://ebok.multimedia.pl/Logowanie?ReturnUrl=%2f

pprzybylski80 wrote:

Because when I have it connected like this, there is no internet anywhere.

After changing the Technicolor to a modem, you will have to disconnect everything (Technicolor and Asus) from the power supply for at least 30 seconds, wait and connect the power to both devices again - Technicolor will get a new IP, and only then it will work with Asus.

pprzybylski80 wrote:

With various combinations of connections, the Internet is only on the TV.

Maybe you've already combined something and switched to bridge and the net works only on one device?

He could not move because it is not even possible without the intervention of the service with limited access to the settings. Unless he has a routable IP because he bought a fixed IP.

Another thing is that it does not have to have a currently routable IP address on the router and only buying a fixed IP address service will allow you to switch to modem mode through the service.

All that remains is to contact the operator or check as he proposed @KOCUREK1970 .


The current problem may be identical addressing in DHCP in both routers, in Asus you should first turn off DHCP and check how it works.

Some routers can be used as a switch, it is worth checking if something will connect to the LAN input (yellow) after disabling DHCP in Asus.

@pprzybylski80
Do you have access to the master and the option to change to bridge / modem mode? If so, first reset to default Asus settings and set from scratch after connecting to the operator's router after its restart.

KOCUREK1970 wrote:

Now you have a mish you have there and it is no wonder that some of the equipment does not work.

Does a colleague suggest with this statement that connecting two routers one after the other, where both perform NAT on the ports described LAN (i.e. a situation where there is a double NAT, which can be searched in Google under the term Double NAT), is in any way incorrect or can it generate a problem that connected devices do not have access to the Internet at all?

takijasiu wrote:

Does a colleague suggest with this statement that connecting two routers one after the other, where both perform NAT on the ports described LAN (i.e. a situation where there is a double NAT, which can be searched in Google under the term Double NAT), is in any way incorrect or can it generate a problem that connected devices do not have access to the Internet at all?

Exactly and only what I wrote.

So I reset the Technicolor and it works for now, but the net is very slow. Is it the fault of Asus? Model RT-AC51U. Max cable speed 90 and I have bought 300.

pprzybylski80 wrote:

but the net is very slow. Is it the fault of asus? Model RT-AC51U. Speeds on the cable max 90 and I have bought 300.

Yes, this is normal, this Asus has only 100Mb LAN / WAN ports - it will not be faster on this Asus.

KOCUREK1970 wrote:

takijasiu wrote:

Does a colleague suggest with this statement that connecting two routers one after the other, where both perform NAT on the ports described LAN (i.e. a situation where there is a double NAT, which can be searched in Google under the term Double NAT), is in any way incorrect or can it generate a problem that connected devices do not have access to the Internet at all?

Exactly and only what I wrote.

Double NAT generally works. As long as the IP ranges in the LAN part on both routers are different.

Also, giving advice to eliminate double NAT is rather unreliable.

Added after 12 [minutes]:

pprzybylski80 wrote:

[img-0] So it's supposed to be connected like this? Technicolor is probably in bridge mode, because it can't run wifi. [img-0]

Connect your computer to the LAN port on the technicolor, let the computer get the address via DHCP and show what address you got, and what gateway and DNS server.

Apparently, if it will be an address from private ranges - i.e. 192.168.xx, 10.xxx or 172.16.xx to 172.31.xx - it is very likely that Technicolor is configured in router mode. Unfortunately, I don't know if multimedia gives a public IP, so it's possible that when working in bridge mode you will also get a private IP.

Theoretically, it should be possible to check it with the antenna cable disconnected - i.e. Techcolor working in router mode should broadcast IP from the same range, regardless of whether it is connected to cable or not. However, it is possible that the Technicolor behaves differently when the antenna cable is disconnected.

takijasiu wrote:

Also, giving advice to eliminate double NAT is rather unreliable.

It's important that it's effective.

I can't connect my computer directly to the technicolor, because I have a laptop without a LAN cable input.

What router do you recommend to manage 300mb? The cheaper the better. Or what to look for when buying?

After all, I already wrote you in #8 what you need to do without any expenses.

At least a router with 1 Gbps input and the same on outputs. For me, Netgear Nighthawks work well in a small home network.


First connect to the wifi of the reset Asus and configure it starting from the Internet connection.
Set up the same net as you had before in Technicolor.

pprzybylski80 wrote:

I have a laptop without a LAN cable.

What exactly is the wifi network card in this laptop?
Type, brand, model, markings?

I have no way to connect to the Technicolor laptop with a cable, because my laptop does not have an input to connect the cable.

@pprzybylski80
This is not an answer to my questions.

Then do not connect, as you have already switched to bridge, connect to Asus and set it.

My laptop is a 2016 MacBook Pro.

Added after 26 [minutes]:

Gentlemen, thank you for your help. I think it will end with replacing Asus with the best model, because even if I set it up perfectly, the internet will not be faster than the 100mb/s that this router supports.

Added after 4 [minutes]:

Will the Asus RT-AS1200 V2 be suitable for speeds of 300mb/s?

pprzybylski80 wrote:

Will the Asus RT-AS1200 V2 be suitable for speeds of 300mb/s?

No - LAN/WAN is only 100Mb.
For a router, where you can effectively push 300Mb wifi (if the macbook allows), the cost is from PLN 300 upwards (with an emphasis closer to PLN 500).

I'm more concerned with the cable so that it is 300mb/s. Wifi can be 100mb/s.

pprzybylski80 wrote:

I'm more concerned with the cable so that it is 300mb / s. Wifi can be 100mb / s.

You have three options:
1. Put your current router into AP mode. Then after WiFi it will be up to 100Mbps and you connect gigabit clients directly to the operator's device and you have as much on them as the link supports. The operator's device works as a router.
2. You are buying to advertise WiFi access point. You connect a cable to the operator's router. Cost PLN 150. The result is the same as in point 1.
3. You buy a router with a processor that supports NAT with a throughput of 300 Mbps or more. You move the operator's device to the bridge. The prices of such routers are at least PLN 300-400.

pprzybylski80 wrote:

I'm more concerned with the cable so that it is 300mb / s. Wifi can be 100mb / s.

It doesn't change anything - if the LAN / WAN port in the router is only 100Mb, whether wifi or cable will still be only 100Mb.

IC_Current wrote:

pprzybylski80 wrote:

I'm more concerned with the cable so that it is 300mb / s. Wifi can be 100mb / s.

You have three options:
1. Put your current router into AP mode. Then after WiFi it will be up to 100Mbps and you connect gigabit clients directly to the operator's device and you have as much on them as the link supports. The operator's device works as a router.
2. You are buying to advertise WiFi access point. You connect a cable to the operator's router. Cost PLN 150. The result is the same as in point 1.
3. You buy a router with a processor that supports NAT with a throughput of 300 Mbps or more. You move the operator's device to the bridge. The prices of such routers are at least PLN 300-400.

So with Asus should I do what you wrote in post No. 8? And connect the TV and consoles with a Technicolor cable?