[fizikz]

My R7000 suddenly started behaving very strangely.

* WAN-side: Internet stopped working downstream of the router (internet is working at modem). The modem's ethernet light does not indicate a connection to the router.

* LAN-side: Devices either could not connect or took a long time to connect.

* Web admin takes an abnormally long time to reach or navigate. Feels like dial-up or worse. Page elements load very slowly piece by piece or sometimes not at all. Sometimes it errors out with "connection reset by server".

* Connecting just a laptop to a LAN port indicates the link speed at 10 Mb/s.

* Settings weirdness: I can't add an authorized SSH key (it doesn't "stick" after applying). I was able to turn on password login for SSH, apply, and log in to SSH successfully. EDIT: After many attempts, adding the SSH key succeeded, and login with key worked..

I tried different ethernet cables, ports, and power supply.

I hope it's not dying/dead. What could be the issue? The only thing that's been on my mind is flash failure since the traffic counter is on (about a year), though I'm not sure what behavior would be expected in that case.

Very luckily I have a spare router on hand, but I already miss the R7000

Now my thought is to reset ("nvram erase && reboot" recommended or something else?). Before I do that, and while I have an SSH connection, is there anything I should check or try? Any idea what is going on?

[@m0eb@]

You have not mentioned which dd-wrt version you are using - but in such a situation I would try the following:

1. Just switch off the router, give a 10 second gap before restarting - and see if things get okay.

if not...

2. Try to erase and reboot, install a stable dd-wrt version this time, and do the settings from scratch. (Check the threads on R7000 for the latest stable version).

if that too did not work ...

3. I would try to revert to stock (nmrpflash works perfect for the R7000) and see if all's well while runing stock firmware.
If stock works - no reason why dd-wrt should not. IF it does not work with stock - that's a different problem

[fizikz]

It's been running the (sadly last) r40270M Kong build for probably about a year. I kind of doubt the problem is with dd-wrt, since it seemed fine (often months of uptime)... until this suddenly happened. No storms or power outages today, although there were some a week ago.

I had it unplugged for maybe half an hour before. I don't think it made a difference.

If there are no investigation suggestions while I have SSH access, I'll go ahead with the nvram erase and reboot.

Thanks for mentioning nmrpflash. I have no intention of running stock firmware, but might as well keep it as a diagnostic back-up.

[kernel-panic69]

You have to reboot for ssh key authentication configs to take, apply doesn't always work. If you are using a Chromium-based browser, there is always a possibility of issues there. Holding onto the last <Kong> build that is slightly dated and un-patched, you may wish to try upgrading to the most recent release:

https://download1.dd-wrt.com/dd-wrtv2/downloads/betas/2020/08-13-2020-r44187/netgear-r7000/

I would recommend at a minimum, however, going to Administration->Factory Defaults and resetting to defaults and rebooting and starting with a fresh new configuration. I personally do not use the ttraf feature.

[fizikz]

Oh, I didn't know ssh key changes need a reboot.

I did "nvram erase && reboot" which succeeded, but the slowness is still there.

Something is seriously wrong somewhere. When trying to transfer the firmware file from my computer to the router, SFTP states "stalled". On the first attempt, the checksum did not match the original file. Second attempt got aborted with a broken pipe. Third attempt is still stalled having transferred only 32KB in 45 minutes. Thankfully I did not try flashing from the webgui...

I also tried measuring "network" performance (router to laptop with a ~6' Cat 5e cable to a LAN port). The results vary a lot ranging from 15 Kbits/sec to 400 Kbits/sec (I wasn't joking when I said dial up!) with lots of retries and many instances of 0 bits/sec.

[@m0eb@]

Try using a different LAN cable.

Or - if this is bugging you too much, you can NMRPFLASH back to stock. Run the router on stock firmware till you are sure that check that all is okay.

If all working with stock firmware - Re-install dd-wrt with all the checks followed (proper reset, nvram reboot and reset post installation, manually entering the settings once again - instead of restoring from backup.

[egc]

Try different powersupply

[fizikz]

I've discovered that the behavior is normal if I connect via wifi. The webgui and settings are functioning fine and the throughput is normal ~100Mbps too.

However, all of the ethernet ports (LAN and WAN) have somehow gone bad. It takes about a minute for a plugged in cable to be detected, it links at 10 Mbits/sec, and the throughput is abysmal(0-400 Mbits/sec) with fluctuations and packet loss.

I haven't tried the stock firmware yet, but it seems like a hardware issue, no?

I have triple checked two ethernet cables and computers, making sure that their ports work and the cables get detected immediately and link at 1Gbps. I have also tried a different power adapter.

Thoughts on how to confirm or rule out ethernet hardware as the issue? Possible repairs?

[kernel-panic69]

Have you had anything other than stock or DD-WRT on this router? Uploaded a modified CFE?

[fizikz]

No, I don't even know what a CFE is. I put dd-wrt Kong on it the moment I got it and nothing else. I bought it used nearly 3 years ago and it has given me no issues until now. The previous owner is an IT professional and told me he had tried a few third party firmwares (I think dd-wrt, openwrt, asuswrt-merlin) but left it on stock since that has the highest throughput.

[kernel-panic69]

If he flashed XWRT-Vortex/AsusWRT-Merlin, and did not roll back the X-Vortex modified CFE, there might be a problem there.

[fizikz]

Is there a way to check? And would a problem remain silent for 3 years and suddenly manifest itself?

[kernel-panic69]

Outside of serial console output on boot, I don't think so. The R7000 doesn't have the bl_version variable in either bootloader that I am aware of off the top of my head. And, yes.

[Alozaros]

[fizikz]

I really don't know anything about serial. Could you suggest the appropriate hardware (UART?), preferably one which can be used with many different devices?

@Alozaros, What do you mean "switch issue"? Capacitors were the next (and last) item on my list to check. I guess I'll be discovering how to disassemble the R7000.

I've never had ethernet ports fail on me, but there's a first time for everything. There were no problems with the R7000 and then suddenly this happened. No gradual problems. But the ports still "work", as in the LEDs light up, cables get recognized, just very slowy, at 10Mbps link rate, and with packet loss.

If any other diagnostic ideas come to mind, please let me know.