Why TP-Link Archer C5 router can't restablish without mac cloning

Anyone else have a TP-Link Archer C5 (AC1200) router that permanently loses it's connection the moment you unplug either it or the cable modem (for example, to move it) or whenever the Internet goes down and comes back up.

Basically, if you interrupt power to the router, it can't re-establish a connection with the Comcast cable modem.

When I call customer support for Comcast, they tell me the Internet is working fine (and plugging the computer into the modem confirms this). Comcast doesn't care what mac address is downstream of it, so, there should be absolutely no need for any mac cloning whatsoever.

When I call customer support for the router, they had me connect the computer to the router and then press the mac clone button.

On then, after cloning something, does the router work again.

I'm confused what is going on.

TP-Link support barely speaks English so I'm just asking if you have the same problem and if you can explain what is really going on.

TIA

Reply to
Ken Cito
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Seems that Comcast is lying...

Reply to
Melzzzzz

I don't think it's comcast because it happens even if I just unplug the router and modem and then connect them back up.

I can connect to the modem from the laptop and it works so, comcast is working.

There is something odd in the TP Link router that *requires* a manual mac cloning just to get it to work.

If someone else experienced this, please explain why this is needed.

Reply to
Ken Cito

Like many other routers, MAC cloning is necessary. You don't have ways to set up MAC cloning in your router's firmware? If you don't want to then did you try ipconfig command with proper switches?

Reply to
Tony Hwang

Cloning is just giving router mac address from laptop. You should figure out how to make router remember *that* mac address so no need to do it all over again.

Reply to
Melzzzzz

Is that the reason? Mac cloning is *required* for TP-Link routers? If so, they should say it on the box, 'cuz I wouldn't have bought it.

My Netgear WNDR3400 router and my linksys WRT54G router *never* needed mac cloning.

Why does only TP-Link *require* mac cloning to work? I don't understand why it would need that just to work properly?

Reply to
Ken Cito

Do you know what is mac cloning?

Reply to
Melzzzzz

Also check for new firmware update for the router.

Reply to
Tony Hwang

Why would the router even *need* mac cloning?

I thought Mac cloning was only for ISPs who REQUIRE a certain static MAC address. Comcast support told me they don't care what MAC address is downstream of them, so, it's something having only to do with the TP-Link "AC" router, I think.

My Netgear wndr3400 "N" router never needed mac cloning to work. My Linkssys WRT54G "G" router never needed mac cloning to work.

Why would only the TP-Link "AC" router *require* mac cloning in order to work?

This is my first AC router. Is mac cloning a "requirement" of the "AC" specification?

If so, they should have said so on the box and I wouldn't have bought the darn thing. Having to clone a mac just to get a router to work makes no sense to me.

Does it make sense to you?

PS: What am I cloning anyway? Why?

Reply to
Ken Cito

On same modem? Probably they cloned mac address of laptop automatically..

Because cable modem requires mac address from laptop...

Reply to
Melzzzzz

Router does not needs mac address from laptop, rather cable modem...

I think they are lying. Either that or you have to reset cable modem in order to accept different mac address...

Reply to
Melzzzzz

These 2 webpages may help you.

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Reply to
Retired

I am still confused. Sorry. I just don't get *why* any cloning is needed.

Here is the screenshot of the router setup that is currently working:

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I don't want to touch anything.

I just want to understand why/which/what mac address cloning is necessary to get it working once the power goes down.

The now-cloned MAC address of C4:E9:84:3D:9E:8C is a TP-Link OIC. It's not the mac address of the Costco Arris/Motorola modem.

So, what I don't get is *who* needs the mac address cloned? Why?

Reply to
Ken Cito

Why does the cable modem need me to give it a mac address at all?

Here is the router web page that is currently working:

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Reply to
Ken Cito

Router is brand new and up to date. It's not actually "my" setup. It's my kid's setup at college.

But I never in my life had to clone a mac address just to get my Internet to work.

I still don't get why either the modem or the router cares what mac address it is talking to.

There's nothing special about the mac address. It's just a bunch of hexadecimal characters.

Reply to
Ken Cito

Is *this* the reason that this crazy cloning is needed?

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"Some cable companies, for some reason, also authenticate the network card in your computer. First it will authenticate the Cable Modem, and then when your computer attempts to get online, they'll check and make sure that you're still using the same computer/network card/etc that you've always used. If you've changed your network card or installed a router, they will deny you access to the Internet. This is why most cable routers have a "MAC Address Clone" (Use Computer MAC address) feature. If you tell your router to clone your network card's MAC Address, it makes your cable provider think that you're still using the same computer/network card to access their services, and therefore they allow your router on the network."

This description above implies that Comcast is requiring both the MAC of the DOCSIS3 Costco Arris/Motorola plus the MAC of the laptop computer, which, is cloned onto the TP-Link router.

Why on earth would Comcast want *two* MAC addresses? Since they're so easily spoofed, why does Comcast care?

Why does Comcast need anything more than the Costco modem's MAC address?

Reply to
Ken Cito

I'm slowly coming to the realization that Comcast is the guilty party here.

Looking at this web page, it seems that Comcast might be requiring *two* different MAC addresses.

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That page says: "If you want to insert a NAT router between your PC and the cable modem, you might want to avoid changing the client MAC address that the cable modem connects to, for either of these reasons: 1. to avoid having to register a new client MAC address with your ISP (if your ISP is one which requires registration of the MAC address of the connected device); 2. to avoid problems with the ISP's DHCP system not immediately issuing a new IP lease when the client MAC address changes.

Many NAT routers intended for the domestic market have the ability to clone the PC's MAC address into the MAC address of the WAN port.

For best effect, you should do the cloning before you first connect the router to the cable modem. To discover how to clone, please consult the documentation for your router.

If the router had already been connected to a cable modem, then after cloning a new MAC address into the WAN port, you must perform the procedures of Swapping computers on the cable modem.

With the cloned MAC address in the router's WAN port, then as far as the cable modem is concerned, it is talking to the original PC.

So, it seems that Comcast is the guilty culprit, because Comcast is

*requiring* (it seems) two exact MAC addresses: a. One (real) MAC for the DOCSIS3 modem, and, b. Another (bogus) MAC for the "computer" that connects to the modem. (Where this "computer" is the router itself.)

Is that correct yet?

Reply to
Ken Cito

Maybe.

I don't have comcast, I live in another country. But I'll try to make educated guesses. :-)

There are several reasons to have to clone MAC addresses. One quite old reason was that the ISP wanted us to connect a single computer. They would provide a modem of some kind with a single ethernet socket for a single computer. They would identify this computer by its MAC address, and refuse to provide service if it changed. Stupid, IMHO.

But people inserted a router in there, to allow more computers, using NAT. This router had to make the ISP think that it still was connected to the same single computer, thus we would clone the MAC address of the computer into the router outside facing port. And of course, the router has to remember this (save settings), or on power reset it would not work.

I think that is your situation.

It is possible that it would accept the new (unchanged) MAC address of the router after sometime, without doing anything. As I said, I don't know comcast. Try rebooting both modem and router, later connect the computer.

Another situation is that the ISP may identify the MAC address on the external port of the modem or router connected to the cable, typically provided by them. If you buy a different router, it will not work unless you clone that external MAC address. This happens with one provider in my country, I understand.

Reply to
Carlos E.R.

Delete cloning from the question. And Let's see the answer. Put the MAC address in the router set up. Is it left default or blank?

Reply to
Tony Hwang

He uses fake email address.

Reply to
Tony Hwang

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