Networking Issue

[Malyk_38]

Good monring everyone, this is my fist post as a new BT customer. The issue I'm having doesn't directly relate to BT but I was hoping someone can help anyway.

I have a fairly simple little home network, I've attached a photo showing a rudimentary diagram of my setup. The setup is identical how I had it with my previous ISP. Basically nothing has changed.

The issue I'm having is that I cant seem to get a link between switch 1 and switch 2. Everything points to the cable but when I connect the cable directly from the router to a device (TV for example) it works. This cable is around 15m long and worked perfectly up until yesterday. It was giving me a constant 500 down and 30 up.

I've probably answered my own question here, but is my issue most likely the cable? It was just a cheap cable on amazon claiming to be Cat7, but I have my doubts about that. Hope someone can help.

[WSH]

If the cable works plugged into another device it seems to rule out the cable and 15m is nothing distance-wise.

Have you tried restarting the switches?  It sounds as though the changes have screwed up the CAM table.  If that doesn’t work, have you tried different ports on the switches?  It’s not unknown for a particular port to die.

[Malyk_38]

Thanks for your response.

Both of these switches are unmanaged so I all I can do is power off, wait and on. No luck with that!

I’ve tried all the ports on both ends, no luck.

The strange thing is that when I plug this cable directly in to the Nest router and then connect to switch 2 (bypassing switch 1) it works but only at speeds up to 100mbps. Similarly if I wire the two Nest routers together I’m only seeing speeds up to 100mbps. Then when I use the cable to go from switch to switch I get nothing.

This is such a strange issue to have. I’ve got a new cable coming today that I will try.

Based on the diagram I attached, it should just be as simple as the diagram shows shouldn’t it? It’s worked fine like that for years. 

[WSH]

Might be an idea to also reboot the router.  I should have emntioned that.

Ah…to get gigabit speeds you need all 8 wires connected but 1, 2, 3 and 6 on their own can give up to 100Mb/s.  Sounds like the cable.  I’d check the pins are clean.  Even though they are gold plated they still get a bit of crude from time to time.

[countrypaul]

Have you tried a different cable between the switches to make sure the switches are not the problem. Occasionally two (or more) problems can show up at the same time and cause confusion when trying to solve so changing each piece in the puzzle one at a time is safest approach.

By the way, Cat7 is not an ISO standard, Cat6, 6a and 8 are ISO standards.

[WSH]

Cat 7 will work fine.

As I understand it the reason it was never formally recognised by EIA/TIA is the Americans being funny about its original use of GG45 plugs instead of RJ45.

[Malyk_38 · Accepted solution]

Thanks for all the help.

It turns out the cable between the two switches was the issue. I don't understand why. With a new, good quality, Cat6 cable everything is working perfectly. I'm seeing my full speed (plus more) on my PC, which is the furthest away wired device. All good!

I must say I've been very impressed with BT since the day I first called them to place the order. I've been a Virgin user/customer since a teenager and I always swore by them. Their broadband service was good enough but finally because of price and their appalling customer service, I cautiously made the switch to BT. So far so good. Happy to be part of the family.