Help needed to configure access 2 different routers from 1 PC at same time ?

[NetorkinghelpSan]

Hello,
I had an old router and had difficulty with local lan transfers on my PC.. its different issue in this topic:
Recently bought a NEW Router and connect same to Internet using PPPOE.
Check my Network Diagram..

https://imgur.com/a/md4GzS7

Everything is working as required, But cannot access both router configuration at one time from my Windows 10 PC.

NEW ROUTER = A
IP range = 192.168.0.1
SSID 2.4ghz = TEST2.4 (Works Perfect)
SSID 5ghz = TEST5 (Works Perfect)

Wireless Settings on NEW router:

https://imgur.com/a/uOdwJHg

Network/Lan Interface on NEW Router:

https://imgur.com/a/Mi7Zu2J

OLD ROUTER = B
Using latest openwrt Firmware
IP range = 192.168.1.1
SSID 2.4ghz = 2.4 OLD ROUTER (Works Perfect)
SSID 5ghz = 5 OLD ROUTER (Works Perfect)

Wireless Settings on OLD router:

https://imgur.com/a/mhavjQx

Network/Lan Interface on OLD Router:

https://imgur.com/a/rIsoRML

To connect to OLD router when everything is running fine and make some SSID changes:
(have to turn off NEW router do a network adapter RESET, then OLD router works fine, but internet does not works as IP range gets changed/updated from OLD Router and cannot access NEW router interface)

To connect back to NEW router:
(have to turn off OLD router do a network adapter RESET, then NEW router works fine, Everything starts working perfectly, but cannot access OLD router Interface)

Old Router SSID Settings in 2.4ghz and 5ghz mode:

https://imgur.com/a/5dxg2H1

Can someone direct to a proper solution please ?
I am not sure how to configure openwrt settings, was done by someone else.

Thanks.

 

[Tech9]

You can't have the two routers connected by LAN port. They both have different LAN IP and run DHCP servers. Convert the second router to Access Point and use it for Wi-Fi and switch only, whatever you need there. Connect the second router's WAN port to your new router's LAN port*. Both routers will be on the same subnet and with one DHCP server from your new router. You'll have access to both UI and will avoid not needed double NAT situation.

* - may be WAN-LAN or LAN-LAN depending on what this old router has in settings. If there is Access Point mode available - WAN (works on LAN too, but may not get time from NTP, model specific). If you do it manually with disabling NAT, DHCP and assigning IPs - LAN.

Internet -> (WAN) New router, Router mode (LAN) -> (WAN/LAN, see above) Old router, AP mode (LAN) -> PC

If you want to use the old router as Wi-Fi extension - set it to the same SSIDs like your new router. Your clients will connect to the best AP they see.

 

[sfx2000]

Or just remove the older router/AP device....

MIght be the best course of action here...

 

[NetorkinghelpSan]

Thanks @Tech9 and @sfx2000
At Present New Router Lan Port is connected to Old Router Lan Port
I require WIFI (2.4 ghz and 5 ghz) on both routers running fine, as distance between both routers is very lengthy and both rooms have few old devices which require 2.4ghz as well.
Need LAN on PC connected to old router for faster file transfers to laptop..

Here comes the most difficult part, configuring OLD router with openwrt
(openwrt was setup over stock tplink firmware few years ago from a technician, no idea)

Not sure how to do this on old router openwrt.
== Convert the second router to Access Point and use it for Wi-Fi and switch only, whatever you need there
== You'll have access to both UI and will avoid not needed double NAT situation.
What would be the IP address of old router in this case ?

== may be WAN-LAN or LAN-LAN depending on what this old router has in settings. If there is Access Point mode available - WAN (works on LAN too, but may not get time from NTP, model specific). If you do it manually with disabling NAT, DHCP and assigning IPs - LAN.
Again trouble doing this on old router

== Or just remove the older router/AP device....
Did you meant to physically remove the old router ? or something else ?

Pardon my knowledge about this stuff, still trying to do it myself as technician wont be available for 2 days (Saturday/Sunday)

 

[Tech9]

What would be the IP address of old router in this case ?

An IP address assigned by the main router's DHCP server or it can be set manually.

Again trouble doing this on old router

It is a bit of trouble and it's actually LAN-to-LAN for OpenWrt. See instructions below:

[OpenWrt Wiki] Wireless Access Point (aka "Dumb" Access Point)

openwrt.org

 

[NetorkinghelpSan]

Thank You very much @Tech9
Openwrt setting is not possible for me, it was done few years ago by someone else.

Earlier from NEW router Lan port was connected to OLD router Lan Port via ethernet.
Changed now
NEW router Lan port is connected to OLD router Wan Port via ethernet.

I just reset the old router and it configured things on its own and works as desired:
I can now ping to both routers at same time without any issues:

https://imgur.com/a/0E4JWrt

Can access both router configuration without issues:

https://imgur.com/a/yNo9rMO

Tried to reboot new router first, all settings work fine
Tried to reboot old router first, all settings work fine.

Network interface of old router now after reset:

https://imgur.com/a/Awg6yeP

It seems problem is fixed or should i share some more screenshots from specific location to confirm ?
Required different SSID for both routers, which is working as planned.

What could have been issue ?
Not a networking expert, but still some knowledge can help in future

Thanks

 

[drinkingbird]

Thank You very much @Tech9
Openwrt setting is not possible for me, it was done few years ago by someone else.

Earlier from NEW router Lan port was connected to OLD router Lan Port via ethernet.
Changed now
NEW router Lan port is connected to OLD router Wan Port via ethernet.

I just reset the old router and it configured things on its own and works as desired:
I can now ping to both routers at same time without any issues:

https://imgur.com/a/0E4JWrt

Can access both router configuration without issues:

https://imgur.com/a/yNo9rMO

Tried to reboot new router first, all settings work fine
Tried to reboot old router first, all settings work fine.

Network interface of old router now after reset:

https://imgur.com/a/Awg6yeP

It seems problem is fixed or should i share some more screenshots from specific location to confirm ?
Required different SSID for both routers, which is working as planned.

What could have been issue ?
Not a networking expert, but still some knowledge can help in future

Thanks

You had two DHCP servers and network segments on a single LAN with no router in between. Now that you have LAN connected to WAN you have a router in between, so it is working.

Can't route between subnets without a router.

 

[drinkingbird]

You had two DHCP servers and network segments on a single LAN with no router in between. Now that you have LAN connected to WAN you have a router in between, so it is working.

Can't route between subnets without a router.

You could have disabled DHCP on one router and put them both in the same subnet (make one .2) and it would have worked also. Essentially at that point one is working as an AP only.

 

[NetorkinghelpSan]

Just found one issue, when OLD router is shut down, ping and connection to both router fail (quite obvious).
But I can still connect to NEW router 2.4 ghz SSID - though not a decent speed.

 

[NetorkinghelpSan]

You had two DHCP servers and network segments on a single LAN with no router in between. Now that you have LAN connected to WAN you have a router in between, so it is working.

Can't route between subnets without a router.

So now OLD router is acting as a DHCP server ?

IP details:
IPv4 Address. . . . . . . . . . . : 192.168.1.163(Preferred)
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Lease Obtained. . . . . . . . . . : 16 September 2023 07:49:50
Lease Expires . . . . . . . . . . : 16 September 2023 19:23:26
Default Gateway . . . . . . . . . : 192.168.1.1
DHCP Server . . . . . . . . . . . : 192.168.1.1

DHCP server is also running on new router (unchanged)

 

[NetorkinghelpSan]

You could have disabled DHCP on one router and put them both in the same subnet (make one .2) and it would have worked also. Essentially at that point one is working as an AP only.

If the above working solution is not proper, request you to guide a little on how to acheive this.

 

[drinkingbird]

If the above working solution is not proper, request you to guide a little on how to acheive this.

You're fine with them daisy chained the way you have them now (now that you have it WAN to LAN), was just offering another way you could have done it if you didn't want double routers and double NAT etc.

Having the two LANs connected together won't work without a few extra steps as mentioned, that's why you were having problems that way.

 

[drinkingbird]

So now OLD router is acting as a DHCP server ?

IP details:
IPv4 Address. . . . . . . . . . . : 192.168.1.163(Preferred)
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Lease Obtained. . . . . . . . . . : 16 September 2023 07:49:50
Lease Expires . . . . . . . . . . : 16 September 2023 19:23:26
Default Gateway . . . . . . . . . : 192.168.1.1
DHCP Server . . . . . . . . . . . : 192.168.1.1

DHCP server is also running on new router (unchanged)

Both are running DHCP, old router DHCP is now only serving new router's WAN and new router's DHCP is serving the client(s). DHCP won't cross a router so they don't see each other now that it is wired correctly.

New router could be placed in AP mode to simplify things but if it is working the way you want you're fine.

EDIT I have it a bit backwards, was looking at your diagram wrong, but same idea just swap old and new in my statement.

Why not just plug the cable into the PC and eliminate the old router?

EDIT 2 ok so you need both wifi and you can't configure the old router. So what you have is fine, just bear in mind any transfers from the PC connected to old router and PC connected to new router would be limited throughput wise to whatever the old router is capable of, which will be less than if they were wired directly together using AP mode etc.

 

[Tech9]

If the above working solution is not proper, request you to guide a little on how to acheive this.

As mentioned above - you have two routers now in double NAT. Clients connected to your old router can access the clients connected to your new router, but not vice versa. Port forwarding from clients connected to your old router won't work without extra settings on the new router. Not ideal home network situation. If you can't change settings on your OpenWrt router - wait for your tech guy. Ask him to make your old router an Access Point.

But I can still connect to NEW router 2.4 ghz SSID - though not a decent speed.

Of course. It's a wireless connection to the new router. Your old router has nothing to do with it.

 

[NetorkinghelpSan]

Both are running DHCP, old router DHCP is now only serving new router's WAN and new router's DHCP is serving the client(s). DHCP won't cross a router so they don't see each other now that it is wired correctly.

New router could be placed in AP mode to simplify things but if it is working the way you want you're fine.

EDIT I have it a bit backwards, was looking at your diagram wrong, but same idea just swap old and new in my statement.

Why not just plug the cable into the PC and eliminate the old router?

EDIT 2 ok so you need both wifi and you can't configure the old router. So what you have is fine, just bear in mind any transfers from the PC connected to old router and PC connected to new router would be limited throughput wise to whatever the old router is capable of, which will be less than if they were wired directly together using AP mode etc.

Ok so ignoring the DHCP part, I dont have issues with connecting to SSIDs from both routers, whatever room I am in.
I require WIFI on PC as well and have its own small network, hence adding a router was required.
My motherboard has onboard wifi (but it is quite pathetic, spend a month getting better speeds but nothing, even contacted Asus but they said, thats the speed limit)

Did you meant to say, PCs connected to LAN via New Router will not be able to talk to PCs connected to LAN via Old Router ?
This is as well a requirements, I guess I have to start everything again from scratch then..
Or you can point what changes to make ?

 

[NetorkinghelpSan]

As mentioned above - you have two routers now in double NAT. Clients connected to your old router can access the clients connected to your new router, but not vice versa. Port forwarding from clients connected to your old router won't work without extra settings on the new router. Not ideal home network situation. If you can't change settings on your OpenWrt router - wait for your tech guy. Ask him to make your old router an Access Point.

Does that means, I cannot access PCs which are connected to LAN via NEW and OLD Router ?

 

[NetorkinghelpSan]

If I am connected to SSID of new Router and try to access my PC (connected to LAN port of old router) data via Samba protocol it wont find any files
(trying to access Media files from VLC Media player on Tv kept in old router room)

Now, If I am connected to SSID of old router and try to access my PC (connected to LAN port of old router) data via Samba everything work fine, all files/folders are accessible.

Issue is not completely resolved, I will have to get a technician to help me fix this.
Can this problem be solved online ? IF I provide access to my PC remotely to anyone ?
So that tthe person can do require changess.

 

[drinkingbird]

If I am connected to SSID of new Router and try to access my PC (connected to LAN port of old router) data via Samba protocol it wont find any files
(trying to access Media files from VLC Media player on Tv kept in old router room)

Now, If I am connected to SSID of old router and try to access my PC (connected to LAN port of old router) data via Samba everything work fine, all files/folders are accessible.

Issue is not completely resolved, I will have to get a technician to help me fix this.
Can this problem be solved online ? IF I provide access to my PC remotely to anyone ?
So that tthe person can do require changess.

Yes, that's exactly how it will work. As far as old router is concerned, anything on the LAN of the new router is on the "internet". Likewise, the firewall and NAT in that old router will block any attempted inbound connections from the "internet".

You can make it work but you will need to set up port forwarding rules or DMZ on the old router to allow WAN to talk to LAN, plus add a static route on the new router, but it sounds like you're not able to make changes to that old router. So unfortunately unless you replace the old router with one you can admin, or have someone flash that old router back to stock firmware so it easier for you to manage, you're stuck with that behavior. Replacing the old router with one you can put in AP mode is going to be by far your easiest solution.

A couple other possibilities -

Use your old router as the internet facing router (assuming it was already configured for that it should work, or you must be able to get in and change the settings back to PPPoE since you must have turned that off before)? Then make the new router AP only hanging off that (it will also function as a switch for wired devices).

Leave new router as the internet router, disable DHCP on the new router, put its LAN IP in the same network as the "old" router (but a different IP) and then connect their two LANs together (no WAN connection on old router) and that should theoretically work, though a bit messy. Your new router is working as the router in that setup, and the old router would be acting as an AP/Switch and DHCP/DNS server, but not a router.