Another bricked and rescued Archer C8v2

Post new topic   Reply to topic    DD-WRT Forum Index -> Broadcom SoC based Hardware
Author Message
Felpas
DD-WRT Novice


Joined: 20 Aug 2024
Posts: 1

PostPosted: Wed Oct 16, 2024 8:55    Post subject: Another bricked and rescued Archer C8v2 Reply with quote
I'd like to share my experience with my Archer C8v2. After flashing the factory-to-ddwrt.bin file in my Archer C8v2 (appartently without errors) the router went into bootloop.

I tried to install the OEM recoveries using the recovery mode using TFTP64 (Firm renamed to: ArcherC8v1_tp_recovery.bin) with the PC IP set to 192.168.0.66/24, pressing the reset key while booting the router, this forces the recovery mode, and the firmware should be flashed via TFTP automatically, in my case without success). I even tried to install the recoveries via TFTP with commands, but still no success.

I also tried to install the dumps I found in the forum using Putty and TFTP64, after doing that I got the error:

"Could not load flash0.os:: Unsupported function"

And... I thought it was finally hard bicked. In another post of this forum I saw that it was necessary to remove the flash memory chip and write a flash dump in order to recover it. This was not an option for me.

So... since I had nothing to lose, I checked in Putty (SEE step 3) that the router IP was not the one of the original firmware (192.168.0.1) but the one that DD-WRT gives by default (192.168.1.1) I decided to flash the DD-WRT firmware build "02-23-2021-r45820" (ONLY the "archer-c8v2-webflash.bin" file, NOT the "factory-to-ddwrt") via Putty - TFTP, so I renamed it with the name of the Linksys OEM firmware: c8v2_un-up-ver4-0-0-P1[20160520-rel62091].bin and voilà, the router was alive again and with DD-WRT firmware.

I used as a reference a youtube tutorial on how to unbrick Archer C9 using Serial-USB connection.

Previous steps:

- Install TFTP64
- Install Putty
- Install USB uart drivers - Silicon labs CP210x

- Configure COM Port in Putty with the corresponding number (confirm in devmmgmt.msc E.g. COM3) with the following options:

- Speed ​​115200
- Flow control - none

- Configure the network adapter IP to 192.168.1.66/24 (or 192.168.0.66/24 depending on the router IP - SEE Step 3).
- Connect router via RJ45 to port 1 of router
- Connect to serial port as follows using a pogo pin clip, so you don't have to solder anything on the board (4pin 2.54mm) (see attachment).

Steps to recover router from soft brick:

1 - Turn on the router with both TFTP64 and Putty open.
2 - Stop the booting process by clicking ctrl+c (in Putty) until CFE> appears on the screen.
3 - Use ifconfig command to see router IP.

If we have flashed the "factory-to-ddwrt.bin" the IP should have changed to 192.168.1.1 (the original firmware is 192.168.0.1), double check it anyway.

4 - Download the build 02-23-2021-r45820, we only need the file "archer-c8v2-webflash.bin" renamed to archer_c8v2_un-up-ver3-17-0-P1[20150716-rel55646].bin then flash it using the following command in Putty (the file should be located in the TFTP64 folder):

flash -noheader 192.168.1.66:archer_c8v2_un-up-ver3-17-0-P1[20150716-rel55646].bin flash0.trx

Result:

CFE> flash -noheader 192.168.1.66:archer_c8v2_un-up-ver3-17-0-P1[20150716-rel55646].bin flash0.trx
Reading 192.168.1.66:archer_c8v2_un-up-ver3-17-0-P1[20150716-rel55646].bin: Done. 12906496 bytes read
Programming...done. 12906496 bytes written
*** command status = 0

4. Reboot the router.

With all this, I tried to make a complete guide (more or less) about unbricking an Archer C8v2 because I found lots of information, but all spreaded around. If this helps someone and saves you few hours of reading docens of posts I'd be happy.[/img]



Connections.png
 Description:
Connections diagram Router - Board.
 Filesize:  17.94 KB
 Viewed:  650 Time(s)

Connections.png


Sponsor
Display posts from previous:    Page 1 of 1
Post new topic   Reply to topic    DD-WRT Forum Index -> Broadcom SoC based Hardware All times are GMT

Navigation

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum
You can attach files in this forum
You can download files in this forum