TP-Link Archer C50 (EU) V6.0 - 5 GHz interface not present

RIght, but you flashed via OpenWRT's LuCI interface, right? I have exclusively used TP-Link's flashing process, and the TFTP process that TP-Link uses.

Yeah, I tried flashing back from LuCI which soft-"bricked" it. Then I tried via TFTP which did further "damage" and my last try with the spi prog completely f*cked it up.

Right. I didn't know TP-Link's TFTP could do that :grimacing:

There is a message in multiple spots:

WARNING: Do NOT flash the tplink_C50-v[4,6]-squashfs-sysupgrade.bin from the “Downloads” section to the C50 v4/v5/v6 via the TP-Link firmware's web GUI. It will brick the router!

Do you think it would be helpful to still add this elsewhere? It seems unfortunate that people miss it.

Generally support is merged to master and seems to be in good shape. It is important to read the instructions in the commit message.

If you're running the a stock v4 firmware, you can probably prepend a v4 OEM bootloader to the OpenWRT v6 image to get it accepted by the TP-Link GUI and go to the v6 image for OpenWRT. I guess if you prepare an official image for TFTP recovery according to the instructions, you could also get that to work. Then you would be able to go to OpenWRT with the official v6 version of the bootloader. I have no experience with TFTP recovery myself though.

Yeah I may have missed it, I don't remember seeing it. Though that may not reflect on anyone but me xD

I'll get to those suggestions. Splicing together a v6 TP-Link with a v6 OpenWRT image and flashing through TFTP seems to not work -- Looking at Wireshark, Router Advertisements get sent from it, but when SSHing, even though ARP works and the query for 192.168.1.1 gives back the MAC of the router, TCP retransmissions are all that happens. Edit: pinging 192.168.1.1 doesn't work either for some reason, so it might just be a deeper config issue.

So I'll try the v4 suggestion.

Which instructions did you follow? Did you also prepend the extra zeros?

I'm curious how that will work out! My suspicion if that if there is a proper bootloader, it needs to match the version of the running firmware for it to accept it. Somehow an OpenWRT sysupgrade is always passing TP-Link's checks despite that it should not.

None the less, any suggestion you have to improve would be useful. There have been multiple posts that people missed this, so you're not alone :wink:

OK so update. It's a Linux thing again. It works on Windows 10, I just tried it with the v6 TP-Link + v6 OpenWRT firmware. I get the OpenWRT ASCII art. So I'm pretty sure it's just a config issue on my Raspberry Pi. I'll get that sorted.

The instructions in this commit message -- they're really good instructions.

Looking now for the message, I don't see it specifically for the v6. I see it for the v3, v4 and v5, though. Though you may expect a reasonable person to be able to extrapolate, I guess it's possible to make it more explicit.

Currently, [OpenWrt Wiki] TP-Link Archer C50 says:

The Archer C50 v6 CA/EU and RU versions are supported in the main branch, but not yet in a release. Check the nightly builds for images.

There is a link to this discussion forum at the bottom of the page, but maybe if it was in that above message. Maybe if it said something like: ... ?

The Archer C50 v6 CA/EU and RU versions are supported in the main branch, but not yet in a release. Check the nightly builds for images. See this discussion for information and follow the instructions in this commit message carefully. Do NOT flash the .sysupgrade file as-is or you may brick the router.

It seems to be a Linux thing with regards to static IP addresses. When I was setting up a TFTP server on my Raspberry Pi, I had to make the IP address for eth0 static (192.168.0.66/24). I used the following in /etc/network/interfaces:

auto eth0
iface eth0 inet static
  address 192.168.0.66
  netmask 255.255.255.0
  network 192.168.0.0
  broadcast 192.168.0.255
  gateway 192.168.1.1
  dns-nameservers 192.168.1.1

Removing this and rebooting the Pi (so that the network services restart) fixed it. Now SSH works on Linux too.

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Yes, it seems not all TFTP servers are equal. When I tried to use tftpd-hpa with a Devolo device, it did not work. On the other hand tftpd (as in Debian/Ubuntu/Trisquel) worked fine. I never used TFTP with a TP-Link device though, so I can't say anything there, but it seems that generally tftpd-hpa is one to avoid when dealing with router firmware.

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Raspberry Pi OS is based on Debian, so your suggestion should work if I ever (probably) brick it again. Thank you for the help.

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ok so with TFTPD and not TFTPD-HPA i should be able to restore the stock formware?

Hi everyone,
I don't want to be annoying, but I would really appreciate if someone could provide a full memory dump from the router. Not only to recover my own router, but mainly to analyze the full dump.

Greetings,
Leo

by memory dump, you mean the .MTD partitions backup?

Yeah, exactly

There's supposed to be a partition that contains some sensitive info?

Yes, IMO it should be enough to replace the mac address with all FF then it should be anonymized

Possibly. I had this with a Devolo device, not a TP-Link device. So I'm curious what results with a TP-Link device will be :slight_smile:

Maybe the wiki page could be updated to mention working and non-working TFTPD servers explicitly.

mtd

Hello guys, do you have any progress with the 5Ghz interface?

Are you observing particular problems with it?