ASUS RT AC 1900P and lease renewal

[fred999]

Hi,
I have the above router and seem to have a problem with lease renewal, wondering if there has been a fix for this.

I've noticed that if I have a download going, and the lease renewal happens during the download, the download will die because the lease renewal interferes.
There is a 4-5 second interrupt with the network, and I can see the icon in the system tray has the yellow attention sign, indicating no network connectivity. Comes back after 4-5 seconds, but my download has died.

There's exact correspondence with the lease renewal as shown by ipconfig /all, so I'm pretty sure that's the cause. Also tested on my 2nd pc and same thing happens.

Running win7 and router firmware 3.0.0.4.384-20308.

Has anyone heard of this issue?

Thanks.

 

[ColinTaylor]

Are you sure it's actually the lease renewal that is the problem and that's not just a symptom of loosing the network connection?

Lease renewal in itself shouldn't cause an interruption unless for some reason the DHCP server can't give out the same IP address and has to give out a different one (causing the client to reconfigure its network interface).

Check the "Lease time" set on the router's LAN > DHCP Server page. It should be something like 86400.

 

[fred999]

Are you sure it's actually the lease renewal that is the problem and that's not just a symptom of loosing the network connection?

Lease renewal in itself shouldn't cause an interruption unless for some reason the DHCP server can't give out the same IP address and has to give out a different one (causing the client to reconfigure its network interface).

Check the "Lease time" set on the router's LAN > DHCP Server page. It should be something like 86400.

I'm about 99.9% confident it's the lease renewal.
I've done a number of tests, and when I do a ipconfig /all, and see the following:

Lease Obtained. . . . . . . . . . : Wednesday, June 26, 2019 1:07:41 PM
Lease Expires . . . . . . . . . . : Sunday, June 30, 2019 1:07:24 PM

I know on Sun June 30 at 1.07pm there will be an interruption as explained above. And a number of tests have confirmed that. When I can predict that failure so accurately, then I think that's proof.

And the IP doesn't change.

I've changed lease time to 48 hrs, 4 hrs, 24 hrs... always the same result.

However, I don't know why it's doing that. Is it the router, or something else?
And it's happening on 2 different pc's.

Thanks.

 

[ColinTaylor]

I'm about 99.9% confident it's the lease renewal.
I've done a number of tests, and when I do a ipconfig /all, and see the following:

Lease Obtained. . . . . . . . . . : Wednesday, June 26, 2019 1:07:41 PM
Lease Expires . . . . . . . . . . : Sunday, June 30, 2019 1:07:24 PM

I know on Sun June 30 at 1.07pm there will be an interruption as explained above. And a number of tests have confirmed that. When I can predict that failure so accurately, then I think that's proof.

Then something is wrong because the PC shouldn't wait until the lease expires to get a new one. It should renew its lease half way through its duration and if it doesn't get a reply from the DHCP server it will keep trying.

So in the example above the lease duration is 4 days so it should renew its lease at 1:07 pm on Friday 28th.

You can force the PC to renew its lease from the command line with the following command (the "Lease Expires" value should change). Try that and see if you experience the same interruption to your download.

ipconfig /renew

 

[ColinTaylor]

Do you leave these PCs permanently turned on? In the normal use case the PC will get a brand new lease every time you power it on. So unless your PC is left running for 4 days it shouldn't be an issue.

 

[fred999]

Then something is wrong because the PC shouldn't wait until the lease expires to get a new one. It should renew its lease half way through its duration and if it doesn't get a reply from the DHCP server it will keep trying.

So in the example above the lease duration is 4 days so it should renew its lease at 1:07 pm on Friday 28th.

You can force the PC to renew its lease from the command line with the following command (the "Lease Expires" value should change). Try that and see if you experience the same interruption to your download.

ipconfig /renew

I did an ipconfig /renew and got this error message:

C:\Users\User>ipconfig /renew
Windows IP Configuration
An error occurred while renewing interface Local Area Connection : unable to con
tact your DHCP server. Request has timed out.

I started a download just prior, and it did not affect the download.

Did an ipconfig /all just prior and just after and the lease expires did not change.

Actually, my example above of the lease renewal date was from my pc at work.
The real renewal here at home is :
Lease Obtained. . . . . . . . . . : June-24-19 9:12:14 PM
Lease Expires . . . . . . . . . . : June-28-19 9:12:15 PM
so tomorrow at 9.12pm.

Thanks.

 

[fred999]

Do you leave these PCs permanently turned on? In the normal use case the PC will get a brand new lease every time you power it on. So unless your PC is left running for 4 days it shouldn't be an issue.

I only reboot this pc maybe every 3-4 months, always on.
My 2nd pc I just hibernate, also reboot every few months.

I'm looking at the router DHCP, and it's very basic. I have everything at default, except for 1 static IP, so no idea what could be the issue.

Thanks.

 

[dave14305]

Any other dhcp server on your network?

 

[ColinTaylor]

What network adapters do these PCs have? Are they wireless?

If you issue the following two commands does it work or do you get the same DHCP error as before?

ipconfig /release
ipconfig /renew

 

[fred999]

Any other dhcp server on your network?

No, only this router.

Thanks.

 

[fred999]

Then something is wrong because the PC shouldn't wait until the lease expires to get a new one. It should renew its lease half way through its duration and if it doesn't get a reply from the DHCP server it will keep trying.

So in the example above the lease duration is 4 days so it should renew its lease at 1:07 pm on Friday 28th.

You can force the PC to renew its lease from the command line with the following command (the "Lease Expires" value should change). Try that and see if you experience the same interruption to your download.

ipconfig /renew

It's wired through a switch. Realtek PCIe GBE Family Controller.

I did the commands and no errors. I see that the lease renewal has changed when I look at the router.

Lease Obtained. . . . . . . . . . : June-28-19 7:29:34 AM
Lease Expires . . . . . . . . . . : July-02-19 7:29:34 AM

C:\Users\User>ipconfig /release

Windows IP Configuration


Ethernet adapter Local Area Connection:

Connection-specific DNS Suffix . :
Link-local IPv6 Address . . . . . : fe80::6d76:7b0d:8d16:41b5%11
Default Gateway . . . . . . . . . :

Tunnel adapter isatap.{88FA40ED-1B48-4861-AEE2-10DC262B9F6C}:

Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :

Tunnel adapter Teredo Tunneling Pseudo-Interface:

Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :

C:\Users\User>ipconfig /renew

Windows IP Configuration


Ethernet adapter Local Area Connection:

Connection-specific DNS Suffix . :
Link-local IPv6 Address . . . . . : fe80::6d76:7b0d:8d16:41b5%11
IPv4 Address. . . . . . . . . . . : 192.168.1.106
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . : 192.168.1.1

Tunnel adapter isatap.{88FA40ED-1B48-4861-AEE2-10DC262B9F6C}:

Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :

Tunnel adapter Teredo Tunneling Pseudo-Interface:

Media State . . . . . . . . . . . : Media disconnected
Connection-specific DNS Suffix . :

 

[ColinTaylor]

If you can recreate the problem ("unable to contact your DHCP server") on demand by issuing the "ipconfig /renew" without previously doing a release, I suggest you plug the PC directly into the router and test it again. If the problem only occurs when going via the switch then that is the likely source of the problem.

What is the make and model of the switch?

 

[fred999]

If you can recreate the problem ("unable to contact your DHCP server") on demand by issuing the "ipconfig /renew" without previously doing a release, I suggest you plug the PC directly into the router and test it again. If the problem only occurs when going via the switch then that is the likely source of the problem.

What is the make and model of the switch?

The switch is Trendnet TEG S80G.

I connected directly to the router and did ipconfig /renew and got the same error, after about 20 seconds of delay:

C:\Users\User>ipconfig /renew

Windows IP Configuration

An error occurred while renewing interface Local Area Connection : unable to con
tact your DHCP server. Request has timed out.

Thanks.

 

[ColinTaylor]

Thanks for testing. Wow, that's strange.

Are you using MacAfee firewall software on the PCs by any chance?

 

[fred999]

Thanks for testing. Wow, that's strange.

Are you using MacAfee firewall software on the PCs by any chance?

No, I'm using Avast, but the firewall is only Windows standard, nothing special.

 

[ColinTaylor]

No, I'm using Avast, but the firewall is only Windows standard, nothing special.

Just for the test I suggest that you temporarily disable Avast and the Windows firewall and see if that makes a difference.

Also, run services.msc and check that DHCP Client is running.

 

[fred999]

Just for the test I suggest that you temporarily disable Avast and the Windows firewall and see if that makes a difference.

Also, run services.msc and check that DHCP Client is running.

Did that, and still the same result.

Since the same problem on both pc's, that means router has the issue doesn't it?

Thanks for your ideas.

 

[ColinTaylor]

Since the same problem on both pc's, that means router has the issue doesn't it?

Not necessarily. By the same logic you could say that both PCs are running Windows therefore it must be a Windows problem, or both PCs have Realtek adaptors therefore it must be a Realtek problem, etc.

That said, your firmware is very old so it may be a bug that's subsequently been fixed. You should really update the firmware anyway.

 

[fred999]

Not necessarily. By the same logic you could say that both PCs are running Windows therefore it must be a Windows problem, or both PCs have Realtek adaptors therefore it must be a Realtek problem, etc.

That said, your firmware is very old so it may be a bug that's subsequently been fixed. You should really update the firmware anyway.

I will be updating the firmware. I read through the update notes, but didn't see anything that referenced lease renewal.
Anyway, thanks for your help.