The LAN port on the router does not work. What is the difference between LAN and WAN ports and what are they for?

Did your router's WAN port burn out after a thunderstorm? Quite a common problem in the spring and summer. Although, this can happen without a thunderstorm. My TP-Link RL-WR1043ND v1.6 router's WAN port failed on a sunny summer day.

What to do? Buy a new router? No. We'll go the other way. Probably, many users know that there are alternative firmwares that significantly expand the functionality of home routers. The most famous of these projects are OpenWRT and DD-WRT. For myself, I chose OpenWRT due to its openness and abundance of configuration instructions.

In particular, alternative firmware allows you to assign one of the router’s LAN ports as a WAN port, because structurally all ports on the TP-Link RL-WR1043ND belong to one switch, and their division into WAN and LAN occurs at the software level, with the only difference being that the software The manufacturer's software does not allow you to assign ports as the user wants. Of course, who will buy new devices then? :)

The process of flashing the TP-Link RL-WR1043ND v1.6 router with alternative OpenWRT firmware

And so, open the table of compatible equipment on the OpenWRT website and find your router there. The table indicates that the first version of WR1043ND (1-1.11) can install OpenWRT 12.09. If you open the page dedicated to this router model, then among a lot of useful information you can find a firmware compatibility table, in which for v1.6 it is recommended to install the stable version of OpenWRT Backfire 10.03.1 firmware. We will install it. A detailed description of the firmware process can be found, so we won’t dwell on it. I will only add that 12.09 is being flashed just as successfully.

Reassigning the WAN port of the TP-Link RL-WR1043ND v1.6 router

We have successfully installed the OpenWRT firmware and can proceed to assigning a new WAN port. To do this, go to the router’s web interface and open the Network > Switch tabs. There you will see the router switch configuration, which has 5 ports. Port 1 is our “factory” WAN. We turn it off, and instead turn on Port 5, which corresponds to port 4 on the router. Just make the settings look like in the image:

You can assign any other port by making the same settings. Upon completion of the operation, click “Save & Apply” and connect the cable from the provider to the new port.

Conclusion

Thus, we restored the functionality of TP-Link RL-WR1043ND v1.6 and avoided the need to buy a new router, instead losing one of the LAN ports.

In theory, in this way you can bring back to life any router that is supported by OpenWRT, since the Ethernet ports of home routers are most often made in the form of a single switch.

Today we will talk about what a router’s WAN port is, how to configure it, and how it differs from a LAN. This solution is used for routers to the Internet. The correct configuration of this channel ensures stable operation of network equipment.

Procedure

First of all, let's discuss how to configure the WAN port. So, we connect the router to the network. Using (usually included in the kit of the above equipment), we connect the LAN port of the router and a computer or laptop. We turn on both devices. We are waiting for the personal computer to finish loading. Open the Internet browser. Enter the IP address of the router. This value can be clarified in the device manual. Press the Enter key. We are waiting for the equipment web interface to complete loading.

Working in the browser

Next, to configure the WAN port, enter your login and password. This action will allow you to access the ability to configure router settings. Open the WAN menu. In some cases it may be called Internet, or Setup. Fill out the proposed table. Select the protocol type for data transfer, for example, PPTP or L2TP. We indicate the encryption type if this function is supported by the selected provider. Enter the access point or Internet server IP. Fill in the “Login” field, as well as “Password”. Data provided by the provider. Check the box next to the option to automatically obtain the DNS server address. If you need to enter a static IP address for the router, fill in the Static IP column.

Saving settings

We activate the Firewall, NAT and DHCP functions. To do this, check the boxes next to the appropriate items. Some parameters may not be used if you do not plan to connect more than one personal computer to the equipment. To fully configure the WAN port, you must click the “Save” button. Reboot the router. For this purpose, you can use the menu functions, or turn off the device for a couple of seconds and start it up again. We connect the provider's cable to the WAN. We check the functionality of the router. To do this, launch the browser and open several pages in it.

Difference

We've figured out the setup, now let's look at how WAN differs from LAN. A regular router has only one port of the first type and several of the second. Outwardly, they are all the same, but to ensure correct operation of the equipment, confusion is unacceptable. WAN is a global concept that covers and connects a huge number of computer systems around the world. A LAN is a local phenomenon involving a small number of PCs in a small area. The difference between these concepts lies in the purpose of the network. WAN is an external association that connects local groups, as well as individual computers. Network participants are able to interact with each other, taking into account the data transfer rate.

The Internet is the most famous, but not the only WAN network today. That is why on routers there is a port with the corresponding abbreviation. It is designed to be connected to an Internet cable. LAN is used to connect to a local network. Such coverage can extend for a maximum of several kilometers. The WAN network is not limited by territory, and even telephone lines can be used to organize it. The LAN connection uses a direct topology. The WAN network is based on a mixed hierarchical network. In addition, the described channels differ in the data transfer protocols used. The number of clients when connecting to a LAN is limited. Now you know what a WAN port is and how to configure it.

One fine sunny summer day, quite quickly (as usually happens in the summer) a thunderstorm formed over the area where I live. And of course, what would a summer thunderstorm be without thunder and lightning? After one of the lightning strikes, my TP-LINK841N router completely lost contact with the outside world, in other words, its WAN port burned out.

An initial examination of the victim showed that the patient is most likely alive, although not all organs are working. With the WAN port, everything is clear - it cannot be resuscitated, but the LAN ports even seemed to show signs of life, although two of them, the 2nd and 4th, were not able to pull more than 10 MBit (apparently, interference in the provider’s cable during a thunderstorm caused a lot of damage) according to the router), Wi-Fi worked properly and all wireless devices saw the network and successfully connected to it.

The situation is certainly sad, because this was the second victim in a month. Going to the store for a third one, without preliminary preparation - lightning protection for the provider's cable, and it entails grounding, etc., in general, somehow I didn’t want to potentially give up another 400 hryvnia to nature.

As a result, as a result of communicating with my friends on this issue, I was advised to try reassigning one of the 4 LAN ports as a WAN port. Why not.

To obtain the firmware we need, do the following:

1. Let's go here http://download1.dd-wrt.com/dd-wrtv2/downloads/others/eko/BrainSlayer-V24-preSP2/.
2. Select the current year (at the time of writing it is 2014).
3. We select the latest version of the release (at the time of writing it is 06-23-2014-r24461).
4. Based on the router model and hardware version, we find the corresponding section (in my case it is tplink_tl-wr841ndv8).

As a result, we will get (for my router) this path http://download1.dd-wrt.com/dd-wrtv2/downloads/others/eko/BrainSlayer-V24-preSP2/2014/06-23-2014-r24461 /tplink_tl-wr841ndv8/ .

Because Previously, my router worked on factory firmware, to switch to DD-WRT you will need a microcode file called factory-to-ddwrt.bin.

After downloading the required file, go to the web interface of the router - if the router has standard settings (and non-standard ones can always be reset using the reset button), then enter 192.168.1.1 in the address bar of the browser, respond to the login/password request with admin/admin, respectively ( If you have a router configured for your provider, you can find the standard login and password on the back cover of the router). Go to System Tools-> Frimware Upgrade.

Router microcode update page on standard TP-Link firmware

Select the previously downloaded factory-to-ddwrt.bin file to load. Click on the Upgrade button and wait about five minutes, after the update the router will reboot. After rebooting the router, go to the address 192.168.1.1, as a result we will see something like this:

Initial window after dd-wrt firmware

Actually, we are asked to specify a user and password for administration via the WEB interface; the password specified here will also be for the root user when working with the router through the console. After saving the data you specified, the router will immediately ask for it when you enter the WEB interface. At this point, the procedure for changing the firmware can be considered complete.

Now, in fact, let's move on to the procedure for setting up ports. I searched quite a lot of pages both on Google and on the DD-WRT forum, but I still couldn’t find any working recommendations (maybe I did something wrong, but nothing worked - the LAN port didn’t want to work as a WAN), so far I didn’t come across a comment on one of the articles on a similar topic. Unfortunately, I can’t provide a link to the original source (lost in time :)), but the essence of the advice was that in order for the LAN port to become a WAN port, the following set of commands was to be executed on the router (to execute commands and display the result of their work, use the page Administration->Commands):

vconfig add eth1 2
vconfig add eth1 3
ifconfig eth1.2 up
ifconfig eth1.3 up
swconfig dev eth1 vlan 2 set ports "0t 4"
swconfig dev eth1 vlan 3 set ports "0t 1 2 3"
swconfig dev eth1 set enable_vlan 1
swconfig dev eth1 set apply 1
brctl addif br0 eth1.3
brctl delif br0 eth1
stopservice wan
sleep 10
startservice wan

Page for executing commands in the router shell

To execute commands, they must be written (pasted) in the field Commands and press Run Commands.

I can’t say to what extent “by religion” this is the correct method, but it worked for me after executing these commands 3rd LAN port the router was assigned as a WAN port, received an external IP from the provider and everything worked.

In order to avoid having to repeat this whole “thing” every time you boot the router, it’s worth adding this set of commands to Startup. To do this, paste the above set of commands into the field Commands and press the button Save Startup.

In the end it should look something like this:

This is what the page should look like after saving the commands in Startup

At this point, the port transfer procedure can be considered completed. Next, all you have to do is configure the router to work with your provider; I didn’t have the chance to do this because... connection to my provider is via TFTP, i.e. I get the address from the provider's DHCP server.

I will be glad if this solution helped you, like me.

We have already looked at solutions to many problems that you may encounter while setting up a router. In this article we will try to find out why the router does not see the Internet cable that is connected to the WAN connector. Let's look at different cases and possible solutions. It should be noted that the router may simply stop seeing the WAN cable, even if everything worked before. We will look at the example of routers from different manufacturers: TP-LINK, ASUS, D-Link, ZyXEL, etc. The principle of their operation is no different, which means the reasons and problems are almost always the same.

Let's go in order. There is a router, it distributes the Internet via Wi-Fi and cable. In order for it to distribute this Internet, it needs to be connected to the Internet. To connect to the Internet, the router has a special WAN connector (it can also be signed as Internet, or Ethernet). We connect the cable through which we receive the Internet: a network cable from the provider, or from a modem. It looks like this (photo using the example of the TP-LINK TL-WR741ND router):

Everything here is simple and clear. The problem is that sometimes the router simply refuses to see the cable that is connected to the WAN port. There may be several reasons, we will talk about them further. It is clear that if the router does not see the Internet cable, then it cannot connect to it. And if he cannot connect to the Internet, then he cannot distribute it. And we succeed. When the connection on the computer is “Limited” or “No access to the Internet”, and on mobile devices simply nothing opens.

Please note that very often the settings for connecting to the provider are set incorrectly. The wrong connection type and parameters are specified. And most often, this is why the router simply cannot connect to the Internet. I wrote about this problem and its solution in the article:. Be sure to make sure that you set the connection parameters correctly in the router settings. But first, look for possible problems.

Reasons why the router does not respond to connecting an Internet cable

Let's go through all the connection nuances in order to understand what the problem is.

1 We exclude problems on the provider's side. The first thing you need to do is make sure that the Internet works without a router. The easiest way is to connect the cable from the provider directly to the computer’s network card (you may need to configure the Internet on your computer). If everything works directly, but not through the router, then see the instructions further.

If the Internet still does not work on your computer, then most likely the problem is on the side of the Internet provider. Call support and find out. Perhaps they have some problems with their equipment, or you just ran out of money in your account.

2 Checking the WAN cable connection. Turn on the router's power. Check if the cable is properly connected to the WAN connector. Disconnect and reconnect it. Perhaps it just came off, or you didn't snap it all the way.

3 Let's look at the operation of the WAN connector indicator. Almost all routers have an indicator that lights up (blinks) when the cable is connected to the WAN port. Be sure to pay attention to it. As a rule, there is an “Internet” icon next to it, or the inscription WAN.

If this indicator lights up, then the router sees the Internet cable. And it's a matter of setup. At the beginning of the article I provided a link to an article with a solution to this problem. Or simply open the instructions for setting up your router on our website and configure it.

Well, if the power is on, the cable is connected, and the WAN indicator (light) does not light up at all, then the problem is most likely in the router itself (for example, the WAN port burned out, read below about this), or in the cable. You won't be able to do anything in the settings themselves.

4 We check the operation of the Internet cable. As for the cable itself from the Internet provider, the contacts may simply come loose. And it just needs to be re-compressed. But, if the Internet works on the computer, then the problem in the cable can be ruled out.

You can try moving the cable itself, and at this moment look at the connection indicator on the router panel. If something has moved away there, then most likely you will understand it, since the indicator will light up.

And if you determine that the problem is in the network cable, then it needs to be crimped again. You can do this yourself, but you will need a special tool. The easiest way is to call a specialist from your provider.

The router does not see the WAN cable. How to solve a problem?

If you still find out that the problem is in the router (and the Internet indicator does not light up), then there are not many options. In case the WAN port burns out, and this is the most common problem (of those that may be on the router side), then you can try to flash it with alternative firmware, and replace the WAN port with a LAN port. I will write about this in more detail below.

As for the settings, it’s unlikely that you’ll be able to do anything there.

Be sure to reset your router. Press the RESET button for 10 seconds while the device is turned on. Here are the instructions.

On TP-LINK routers, when trying to configure the Internet (on the WAN tab in Control Panel), you will see the inscription WAN port is unplugged! (There is no cable plugged into the WAN port!).

It all depends on the model of your router. In any case, it will not be possible to set up the Internet, since the router cannot detect the WAN cable.

If the WAN port of the router is burned out

It’s not uncommon for the WAN port itself to burn out. Well, it’s clear that the router will no longer see any cable. As a rule, this happens after a thunderstorm or power problems. Although not necessarily, there may be other reasons. But in a severe thunderstorm, it is better to disconnect the network cable from the WAN port of the router. Just in case.

What to do in such a situation? You can take the router for repairs, or buy a new one. But there is another option. If the WAN port really burned out, and the Wi-Fi network and the router itself are working normally, and you can go into its settings, then you can try to flash the router with alternative firmware, which has the ability to assign one of the LAN ports as a WAN port. I will try to write in more detail about this method in a separate article. In the meantime, you can search for such firmware for your router on the Internet. Ask something like this: “alternative firmware for TP-LINK TL-WR841N.” Just substitute your router model there.

It’s not a fact that everything will work out, but you can try. Moreover, considering the fact that otherwise you will most likely have to buy a new router.

conclusions

If you find out that the problem is not in the cable, and not in the provider, but in the router itself (and the WAN indicator does not light up), then most likely this is a technical failure. As we already found out above, the WAN port usually burns out. Next, we either repair/replace the router, or try to flash it with alternative firmware and use the LAN port instead of the WAN. You can also check the router with friends, for example. By connecting it to their internet.

Hello friends! A month ago, our reader Vitaly I encountered an interesting problem: after a thunderstorm, his router stopped working. What exactly happened, and most importantly, what solution was found, today’s article is about all this. The narration is told in the first person.

Somewhere in July of this year there was a severe thunderstorm and on that day my microwave oven and stereo system (which I used to play sound from the computer) broke down and the Internet went out. What’s interesting is that I checked the fuses at the furnace and the center - they were intact! I sent it in for repairs: in both cases the transformer windings burned out. I’m not particularly specialized in electronics, and it remains a mystery to me why the fuses are intact, but the windings of the transformers burned out. By the way, they have already been repaired and are back in operation.I began to understand the Internet. My Internet is distributed through a Zyxel Keenetic GIGA router. I clicked on diagnosing network problems, and I got the error DNS server is not responding.I Googled possible solutions to this problem - I scoured the entire Internet in search, but nothing helped. I really tried everything I found on this problem. Interestingly, I could enter the router settings interface, change settings, save them, and do other actions, but there was no Internet access, although the network was working.

I contacted the provider, he fiddled with himself and said that everything was fine on his side. I contacted Keenetic technical support, described the problem, and they advised me of an unusual solution. It is as follows: when you purchased the Zyxel Keenetic GIGA router, it had the first version of firmware, its interface is like this.

Everything is very clear and informative and I got used to it, but there was an experimental version of firmware v2 for Zyxel Keenetic GIGA (on GIGA II and GIGA III it had already become the main one) and I was advised to flash it. The idea was that the second version allowed assign one of the four LAN ports as WAN, to which the Internet cable fits. I updated the router to the second version and in the settings assigned the first LAN port as the WAN port.

In principle, I could assign any of the LAN ports. The cable from the computer's network card was plugged into the third LAN port.

I checked the network diagnostics - the situation is the same - the DNS server is unavailable. I contacted the provider again - within three minutes my Internet was working! Nevertheless, in this situation, I again tried to assign the router’s WAN port to connect to the Internet, but the result was negative - the network worked, but there was no Internet.

That is, as a result of a thunderstorm, the WAN port of the router went down and if not for the unique ability to reassign the port, it would hardly have been possible to return it to operation. By the way, this router has two USB ports, which greatly expanded its capabilities, but as a result of the thunderstorm, they, unfortunately, also failed. But the main thing is that I have the Internet!