Hi @Aveamantium 

Thanks for posting in our business forum.

Please contact your ISP regarding this matter.

This was mainly due to the DHCP renewal and lease time they have defined. Looks like you have a 24-hour lease time and they require re-authen every 24 hours.

There is no way to fix this from our end. What you can do is to avoid this log by disabling this log in the settings.

Hi @Aveamantium 

Thanks for posting in our business forum.

Aveamantium wrote

  @Clive_A  Thank you for your response...  I've checked in with the ISP and they are reporting no issues on their end.  I tend to agree with them as I have an ER605 that I've tested behind this same modem/ISP and do not have this issue.  Given that the referenced thread in my first message described the same issue using the same hardware (albeit version 1), my suggestion would be to run this by the development engineers to see if they have any input.  

 

In the meantime, I'll go ahead and follow your suggestion of ticking off the WAN down as an alert...

It is not going to be a problem on their end or they could notice a problem. But it is how their system works that affects the router's WAN function. I have explained that the lease time is the whole reason why you saw that error. You should consult with them on this if they can prolong the lease time as long as possible.

Hi @Aveamantium 

Thanks for posting in our business forum.

Aveamantium wrote

I'm having similar issues as this post WAN drops every hour exactly - Business Community (tp-link.com) but mine only drops every 24 hours (must get a 24 hour leaase).  I had the router restart in the middle of the night to not cause problems when the connection drops, but it is annoying to get the WAN Down alert every day.  I've had two ER605s (version 1 and 2) connected to the same modem/ISP in the past w/o issue.  I'm also reaching out to my ISP but since I had no issues with the ER605s, and based on the referenced thread, seems to be a firmware issue with the ER7206?  Below are my logs, which repeat daily.  It seems to try to start the renew process at the 12 hour mark (makes sense as that is half the lease time), fails at the 24 hour mark, goes down briefly, renews, and then 6-7 min later the lease expires/renews again(strange?).

 

So, I can direct you on how to prepare the stuff and verify if this is a problem on your ISP or not.

Put the fact first:

Your ISP did not notice a problem because the DHCP server works and indeed sends an IP to you. As long as you get an IP address, they don't care about if you have a problem or not. It works and you have Internet. They don't bother to look into the reason why and explain that to you.

Unless you lose Internet and you contact them they'll transfer you to the on-site engineer.

AFAIK, ISPs don't usually explain how the system works for you. Because they just provide the Internet and nobody on their end would like to explain how DHCP works, how WAN works, and how their system works.

As I have explained, I did not think this was a problem with the router because the DHCP works in that way.

Here's why based on what I saw:

1. DHCP actually works. There is no problem. The log usually reflects the fact and reality that your router indeed renewed its IP address and it failed as your ISP did not respond to the renewal. So it started a new DHCP session by sending the discovery.

2. DHCP renewal in a very short time which reflects that your ISP was giving you an IP for a short time.

As you mosaiced the IP, I don't know if they reassigned the same IP. Could be that they arranged the IP on their end which caused the logs like that.

Some questions:

1. Did you get the same IP address in the picture above?

If you are not getting the same IP, it will only verify what I explained. This is not a problem on the router but you actually start a new discovery and walk through the DHCP again.

The ISP set the lease time to a very short time.

2. How many logs like this happened during the 2-3 AM? The whole process took how many minutes before it stopped generating logs similar to that?

I actually run the router in the office and my home. Zero problems like this on different models. I took some models back and test and they don't behave like this. I am getting the dynamic IP on my WAN as well. Public IP address. So I assume it is your ISP issue or something special on it to cause this.

My ISP refreshes the WAN every 24 or 48 hours.

Wireshark on your router and capture how long was the DHCP lease. If they indeed assign you a DHCP with a very short time of lease time, then there is nothing we can do on our end. You should ask your ISP with the Wireshark file for the reason why.

How to capture packets using Wireshark on SMB router or switch

How to Use Port Mirror to Capture Packets in the Controller

Hi @Aveamantium

Thanks for posting in our business forum.

Aveamantium wrote

  @Clive_A Thank you for the reply...  I'm still digging and working with the ISP on this one.  For reference the Lease appears to be 24 hours as the router initiates renewal at 12 hours, fails at 24 hours, starts a new discovery at the 24 hour mark and gets the SAME IP address (WAN goes down while the discovery occurs).  I've swapped in my ER605 for the time being to verify that it doesn't get treated the same way.  Playing the wait and see game to see what happens...  I'll post back with results...

 

As an aside, I was going to "wireshark" my WAN port but the ER7206 ghosts the WAN port (port 2) in the port mirroring settings (see below)??  This does not seem to be the case with the ER605 so I'll run a wireshark test if I see the same DHCP behavior with the ER605 (which I didn't see before switching routers).  

 

 

 

 

Thanks Agian!

Sure. Let me know the result and update.

You can post the log of the new test.  Mosaic the last two parts of your IP address.

Wireshark would also be helpful in resolving the puzzle about the short lease time issue. I will inform the dev to take a look if I have enough information for them.

I will keep an eye on your case.

Hi @Aveamantium 

Thanks for posting in our business forum.

Aveamantium wrote

  @Clive_A Ok, just recieved the DHCP renew on the ER605 for comparison.  I'm also including the log files from the ER7206 for reference.  I left the last part of the IP address unmodified to show that both routers do indeed get the same IP at renew.  What it does appear is my ISP does not allow renewal before the 24 hour lease time is just about up.  Not sure what the ER605 does different to get the IP right before expiration that the ER7206 does not, but whatever it does makes it so the WAN doesn't disconnect.  I'm leaving out the fact that the ER7206 seems to only get about a 10 min lease when it renews from the discovery process (probably some weird ISP thing) but once it renews the short lease it again gets a 24 hour lease and the process below repeats itself.  Obviously the ER605 just gets the 24 hour lease and all is good.  

Can you change that WAN port to another port so the #3 port on the interface? We need to Wireshark this on your ER7206 V2 to check if there is any issue with it.

We need you to Wireshark around the time when it is gonna renew the IP. Since it is every 24 hours, and 12 hours, we have two timestamps, we should Wireshark at two timestamps.

Set up an alarm or a reminder before that timestamp, then Wireshark several minutes earlier. See that bold part, 12 hours and 24 hours timestamp. We gotta start to catpure before the timestamp. And can stop after you see the log stops generating such entries.

Aveamantium wrote

 

Er7206 V2

WAN2: DHCP client getting IP succeeded. (IP-Address=XXX.XXX.XXX.125, Mask=255.255.224.0, Gateway=XXX.XXX.XXX.XXX) -- May 14, 2024 10:39:18  pm

WAN2: DHCP client renewing the lease failed. Began a new discovery. -- May 14, 2024 10:39:12  pm

WAN2: DHCP client lease expired. Began renewing the lease. -- May 14, 2024 10:39:16  am

WAN2: DHCP client renewing IP succeeded. (IP-Address=XXX.XXX.XXX.125, Mask=255.255.224.0, Gateway=XXX.XXX.XXX.XXX) -- May 13, 2024 10:39:20  pm

 

ER605 V2

WAN: DHCP client renewing IP succeeded. (IP-Address=XXX.XXX.XXX.197, Mask=255.255.224.0, Gateway=XXX.XXX.XXX.XXX) -- May 16, 2024 04:00:27  pm

WAN: DHCP client lease expired. Began renewing the lease. -- May 16, 2024 04:00:44  am

WAN: DHCP client getting IP succeeded. (IP-Address=XXX.XXX.XXX.197, Mask=255.255.224.0, Gateway=XXX.XXX.XXX.XXX) -- May 15, 2024 04:00:50  pm

 

 

The key is that we need to find out if there is a problem with the mechanism of the router? (This might not be the case as the baseline of the software is universal.) I think I have met this situation before on ER7206 but did not have any progress on them as others stopped following this matter.

It could also be the ISP did not respond in time and missed the renew time which caused the router to think renewal was not successful and start a whole new DHCP.

Have to find out this by the Wireshark.

Hi @Aveamantium 

Thank you so much for taking the time to post the issue on TP-Link community!

To better assist you, I've created a support ticket via your registered email address, and escalated it to our support engineer to look into the issue. The ticket ID is TKID240530460, please check your email box and ensure the support email is well received. Thanks!

Once the issue is addressed or resolved, welcome to update this topic thread with your solution to help others who may encounter the same issue as you did.

Many thanks for your great cooperation and patience!