Use Old Router As Switch?

BK_123

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Hi guys. I have been wondering whether or not I can use my old Thomson TG782T router as a switch. If I can what would I need to do in order to make this work.
 

BikerEcho

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BK_123

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i have a spare switch here if you want to come and grab it.....lol
I would if I wasn't on the other side of the world. So I went and change the routers default ip from 10.0.0.138 to 139 and I was able to get in, DHCP and DNS are off. Now to test it.
 

BK_123

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So I've hard to hard reset the router. When I disable the DHCP server and restart router, I can't get back in, The routers default IP is set to static according to DHCP configuration page, So I am gonna try setting it as 140 or something like that then restart and see what happens.
 

root

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Hi guys. I have been wondering whether or not I can use my old Thomson TG782T router as a switch. If I can what would I need to do in order to make this work.
simple answer, yes, because it's already a router/switch hybrid.

the 4 ports aren't really individually assigned router ports, (e.g. you can't have multiple internet connections plugged into those. and route traffic down different lines.

the modem part converts the ADSL to whatever is used inside the box, (probably Ethernet) the router part simply provides a link between the internal network and external network routing local traffic locally and outbound traffic to the outside, and inbound traffic from the outside to the inside.

the firewall part works as normal, filtering traffic from the outside that's coming in.

notably as far as the router part is concerned there is only two connections, outside and inside.

then there is the switch, ports 1,2,3,4 of the switch are presented to you, port 5 of the switch is connected to the wireless card, port 6 of the switch is connected to the firewall...


long story short, you can use your router as a switch, because those four yellow ports are connected to a switch internally.
 

BK_123

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So I've been trying to follow the guide that BikerEcho linked me and when I get to turn off the DHCP server I get locked out of the router and have to reset it because the IP address for the router is static. How can I get around this?

 

root

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ok, question is your home network a class A or class C network. you seem to have both addresses entered as local addresses (192.168.1.254 and 10.0.0.138) why are you doing this?

the instructions linked to are: (I'll put some comments in that might be helpful)
4
Set the IP address of the router to an address that will not conflict with the main router on the network. For instance, if the main router is 192.168.0.1, try setting the one to be used as a switch to 192.168.0.2. This setting may be on the status page or the administration page, though it will vary from router to router.
at the same time make sure that on your new router (that everything will be attached to also) that the address you give this device is not a part of the DHCP scope because that could lead to address conflicts later on.

(e.g make your primary ADSL router 192.168.1.1, make your old router 192.168.1.2 make your DHCP scope on the router 192.168.1.10 - 192.168.1.254 / 24)

5
Turn off the DHCP server. This server allows the router to assign IP addresses to the computers connected to it. Because the router will be used as a switch, it no longer needs to perform this function, and the main router on the network will take over this task.
This is the point where you're loosing network connectivity? are you finding that you're loosing connectivity on the class A and class B addresses?
simply turning off the DHCP server should not cause you to loose connectivity.

check on the DHCP server of your other router to see if it's show up with a new address gained from DHCP, (this assumes that you have it plugged into that!)

Lastly.

remember that this device will not be the gateway any more, so even if you end up letting this machine serve DHCP tell it to serve DHCP with the gateway set to 192.168.1.1 (or whatever your gateway is) and NOT the address of the old Thompson router. (as that has no internet connection)
 

BK_123

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I forgot to mention in My OP that it is router/modem and it keeps displaying where message where it's not connected to the splitter, Anyway I can disable that or get around that?
 
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