My network won't work without the re-purposed router in-line. Please help?

[ipodmusicman]

Hi folks,

In preparation for acquiring a new WiFi AP, I decided to take my old AP off my network and an issue arose.

Here is my network setup:

My fibre connection and the router that connects to my ISP is located upstairs. I have an Ethernet cable run from the router upstairs to downstairs to where my home entertainment set up is. I have Ethernet jacks on both ends. In order to get WiFi downstairs, I re-purposed a router which I use as an AP with DHCP disabled connected to the downstairs Ethernet jack. Everything works as expected and has been for the past 8 months.

I bought an 8 port gigabit switch to which I plan to connect all devices in my home entertainment set up to as the re-purposed router is going to go in favour of a Ubiquity AP located somewhere else in the house for WiFi.

I disconnected the re-purposed router and connected the switch to the downstairs jack as well as my devices to the switch and discovered that none of my devices registered as connected and could not acquire an IP address. I thought this was very odd. I took one of the devices and connected it straight to the jack and still no go.

So I connected the re-purposed router to the downstairs jack again and connected it to the switch - voila - all devices, still connected to the switch, could acquire an IP address and all worked fine.

Now the question is ... why wouldn't my devices work without the router (AP) in line? Could it be a wiring issue when the Ethernet cable run from upstairs to downstairs was done?

Please advise?

 

[Muttley]

The Ethernet cable must be working, otherwise you old router wouldn't work as an AP.
Quick way to check this, would be to see if your switch still won't work with another Ethernet cable from the new router to the switch. I'm thinking those yellow ones that come with most routers

To me it seems like there's an issue with the DHCP server.. perhaps you should check that your main router is configured correctly,

 

[Peon]

10 bucks says you got a older Dlink router that your re-purposing. A further 20 bucks tells me in my head that you disabling DHCP in the gui but not writing config afterwards. ie; clicking save and then looking a bit down and tapping 'write config'.

DHCP is definately your issue.

A bit more thinking and im thinking you also need to check why your Fibre router is not handing out IP addresses. Also check that your re-purposed router and fibre router arent using the same IP address.

 

[ipodmusicman]

The re-purposed router is a TP-Link C2. I bought it a few months back as I wanted 802.11ac WiFi downstairs.

What I did now, which made things worse, is that I borrowed a TP Link C2 from a friend and swapped out my fibre router (a TP-Link WR840N) with that one and now I don't get any connectivity downstairs whatsoever. I cannot even ping the re-purposed router downstairs.

However, my PC upstairs, connected straight to my fibre router, has connectivity whether I connect up the C2 or WR840N.

SO, I am starting to think that something is not lekker with the cable going downstairs. Not sure what the chances of that is.

I get connectivity downstairs with the TP-Link WR840N as my fibre router hooked up (I can ping the re-purposed router) and when I swap it for the C2, no connectivity downstairs at all. I just don't understand what the hell is going on.

DHCP settings are all good and both routers are using different IP addresses.

 

[ipodmusicman]

Hi folks. I thought I’d update you on my network. I tested the Ethernet link and found 3 out of the 8 lines within the link not working at all.

In essence, my network has been living on a tight thread. When I have additional Ethernet cables run, I’ll have this seen to.

Thanks for the help.