RT-AX82U - Available memory keeps decreasing until it reaches 0 and then disconnects

[smartbits]

Hi,

I have an RT-AX82U router and as of last night, I noticed disconnects. When I checked the logs I noticed a lot of these entries:

dnsmasq-dhcp[1504]: failed to write /var/lib/misc/dnsmasq.leases: No space left on device (retry in 60s)

I rebooted and after a while, I was disconnected again. I reset the router by pressing and holding the reset button. I setup my network again but this time I connected only my PC through ethernet and my phone through wifi but the same thing is happening. All unneeded services/features are turned off. No changes were made to the router settings recently.

Is this just a defective router? Is there anyway I can find out where the memory leak is?

 

[ColinTaylor]

Where are you seeing the available memory decreasing? The error message indicates that the /var filesystem being full is the problem rather than memory (assuming the RT-AX82U is like the other HND routers).***

*** EDIT: Looking at this post it seems that some of the AX routers are still using tmpfs for /var. So using up all the memory would also cause the "No space left on device" error.

You could try hunting through the /var directories looking for any exceptionally large files to delete. I'd start looking in /var/log.

Alternatively, you could backup your current settings (Administration - Restore/Save/Upload Setting) then do a hard reset. Then do the minimum setup that allows you to log back into your router and then restore your old settings. That ought to clear down /var, but it might just start filling up again.

[Wireless Router] ASUS router Hard Factory Reset - Method 2 | Official Support | ASUS Global

 

[Volt]

Looks like you are affected by this issue: https://www.snbforums.com/threads/r...mory-leak-leads-to-lockup-every-10mins.85018/. Are you on 386 firmware? My RT-AX56U is also affected.

 

[smartbits]

Where are you seeing the available memory decreasing? The error message indicates that the /var filesystem being full is the problem rather than memory (assuming the RT-AX82U is like the other HND routers).

You could try hunting through the /var directories looking for any exceptionally large files to delete. I'd start looking in /var/log.

Alternatively, you could backup your current settings (Administration - Restore/Save/Upload Setting) then do a hard reset. Then do the minimum setup that allows you to log back into your router and then restore your old settings. That ought to clear down /var, but it might just start filling up again.

[Wireless Router] ASUS router Hard Factory Reset - Method 2 | Official Support | ASUS Global

I see it on the status tab, next to where it shows how much memory is being used and how much is free.

Can you please tell me where I can find the /var directories in the router settings?

Thanks for the link to how to do a hard reset. I will try this if I can't find another way to fix this. BTW, do you know how long the warranty is for this router? I've had it for just under 18 months.

 

[smartbits]

Looks like you are affected by this issue: https://www.snbforums.com/threads/r...mory-leak-leads-to-lockup-every-10mins.85018/. Are you on 386 firmware? My RT-AX56U is also affected.

Thanks for that link! Yes, I think this is the exact same issue. My initial thought was that the router malfunctioned and was on the way out but this could indeed be an exploit. I might try connect the WAN to my old router and then connect to my ASUS router for a while to see if this is the cause of the issue and if ASUS can fix it with a firmware update.

 

[ColinTaylor]

Can you please tell me where I can find the /var directories in the router settings?

You'd have to enable SSH access to the router and log in through that. If you're not familiar with using Linux from the command line this is probably not the course for you.

Thanks for the link to how to do a hard reset. I will try this if I can't find another way to fix this. BTW, do you know how long the warranty is for this router? I've had it for just under 18 months.

No idea about warrantee. Consumer protection laws vary by country in any case.

 

[smartbits]

You'd have to enable SSH access to the router and log in through that. If you're not familiar with using Linux from the command line this is probably not a the course for you.


No idea about warrantee. Consumer protection laws vary by country in any case.

I figured out how to connect using putty and ran the command that kljiefw posted in this thread - https://www.snbforums.com/threads/asus-rt-ax89x_9-0-0-4_388_31185-beta.82276/page-6#post-841862 and it has stopped the memory leak. At least for now.