OpenWrt Forum Archive

Topic: Archer C5 AC1200 Stuck in Boot Loop

The content of this topic has been archived on 9 Apr 2018. There are no obvious gaps in this topic, but there may still be some posts missing at the end.

Hey Guys -

Earlier this morning, I was trying to set up my new Archer C5 AC1200 (TP-Link) router which I had briefly used in the past.  Prior to today, it had an older snapshot of Chaos Calmer installed.  Due to it being a snapshot and the time since I flashed it, I decided to upgrade.  I downloaded the latest snapshot and flashed it via LUCI - choosing to not save settings.  I found out later, I used the factory image instead of the upgrade one sad

After 10 minutes, I still couldn't get to LUCI, but could telnet.  I tried SSH, but when asking for my credentials and using the root user, the default password - admin wouldn't work nor would my old password, passwd, root, toor, (empty), or anything else I tried.

I followed steps to restore the factory image (from TP-Link) by using wget to download the latest factory firmware locally, then installing it.  After downloading the bin to the tmp folder, I executed the below command:

mtd -r write /tmp/ArcherC7v1_en_3_15_1_up_boot%28141204%29.bin firmware

This caused the router to reboot after a few seconds, but ever since it's been in a reboot loop.  I tried the 30-30-30 reset without any change and believe it's due to the reset button on the C5 being different from what I've read. 

The best thing I can find is restoring the firmware via FTP in Recovery Mode as shown in the link below, but seemingly cannot get into Recovery Mode.  With the ethernet cable plugged into the WAN port (tried LAN 1, too), I power the router on holding down reset, but it still goes to the boot loop.
https://www.mikepalmer.net/tp-link-arch … -recovery/

Current State
- My ethernet adapter is set to 192.168.1.68 / 255.255.255.0 / 192.168.1.1 (Windows)
- When connected via WAN port and watching the network adapter, it has a red X when not connected (obviously)  For ~1 second ever 20 -30 seconds, the red X disappears as if connected but then immediately goes back to X as the router reboots
- When connected to the LAN 1 port, the exact same thing happens
- Seemingly, there's no difference if I hold reset when powering on or not (when it says that, how long do I hold it after powering on???)

Router Current State
- Stuck in reboot loop seemingly no matter what I do (30-30-30, wifi switch off, holding reset when powering on, etc)
- Lights on front go between all being on for a split second to only a few
- USB LEDs on back (2) stay on at all times and look to be in sync.  They turn off for a split second every time the router reboots itself

Any suggestions?  Surely, there's something I can do.  It's not my first choice, but if only choice, I'll open up and do surgery to access / add serial or whatever is needed.  Have all kinds of solder tools, but would like to do all non-invasive steps first.

Thanks Guys - Wish me Luck!!

UPDATE

So I have done further research and played a bit more with it.  It seems I'm getting closer to resolving the issue, but feel as though I'm missing one key part.  Below are the steps I'm currently trying for which I think I may be leaving something out...

1. Set NIC (Windows) to 192.168.0.66 / 255.255.255.0 / 192.168.0.1
2 Attached ethernet cable between NIC and router's LAN #1 port
3. Launch TFTP Server / Select C:\TFTP / Seelct Netwrok Adapter from step #1 above
4. Downloaded the latest factory firmware for my C5 (ArcherC5v1_en_3_14_3_up_boot(150428).bin) to C:\TFTP
5. Renamed the firmware above to "orig.bin"
6. Using dd for Windows, ran the following command: "dd if=orig.bin of=tplink.bin skip=257 bs=512"  This created "tplink.bin" and echoed the below:
rawwrite dd for windows version 0.6beta3.
Written by John Newbigin <jn@it.swin.edu.au>
This program is covered by terms of the GPL Version 2.
skip to 131584
31744+0 records in
31744+0 records out
7. Renamed "tplink.bin" to "ArcherC5v1_tp_recovery.bin"
8. Held down the reset button on router, powered on, and once WPS LED lit, released the reset button

When doing this, I saw TFTP transfer the file and the boot loop stopped.  Based on the LEDs alone, it seemed that the router was working normally as the LAN Port #1 LED was lit and the WAN port lit when I tried plugging in a cable.  However - I couldn't ping the gateway - 192.168.0.1.  I tried setting my NIC to DHCP, but it didn't pull an address.  Next, I tried rebooting, but it went back to the reboot loop.

What I've Tried:
- The above steps (minus the dd part) using an openwrt firmware with the same results
- Using the firmware file without running dd command

I will note that once TFTP startsa to transfer the file, it's adapter setting goes back to the loopback interface (127.0.0.1) for some reason.  Don't know if that has anything to do with it.

Any suggestions?  Thanks

UPDATE #2

OK, I just tried the same process on a different computer.  I had the same result - but - even though it still reverted back to the loopback adapter once the transfer started, the transfer took 12 minutes instead of > 1 second.  I haven't used TFTP in a while, but seem to remember that it wasn't the fastest.  Am I on the right path?  Below's a screenshot - Thanks
TFTP

(Last edited by BzowK on 5 Jul 2015, 20:27)

Step #5 "orig.bin"
is this a typo mistake

Thanks for the reply.  Yes and no.  I guess I left out typing a step which I should have put between 4 & 5. I used the command line in step 5, but before that renamed the OEM firmware file "ArcherC5v1_en_3_14_3_up_boot(150428).bin)" to "orig.bin.".

Do you have any suggestions?  Thanks

sorry cant help you
I might even be wrong in this one, I read your file ArcherC7v1_en_3_15_1_up_boot%28141204%29.bin  and it has the word BOOT, in my 741 and 842 if I upload a file with boot I will brick it, dont know in your case
Everytime I need to go back to stock I use files with no boot, downloaded from Polish server ftp://tplink-forum.pl/orgin_bez_boot/

(Last edited by danymarc on 6 Jul 2015, 01:18)

FYI - trunk snapshots do not include Luci, which was the initial problem you had after flashing. The factory vs upgrade file is also not a huge deal, as long as you're ok with losing any configuration you may have made. The upgrade file does NOT preserve packages that have been downloaded (e.g. Luci).

Try disabling firewall on your PC. ArcherC5v1_tp_recovery.bin is correct file name for tftp method. I ran into similar issue in past and firewall turned out to be the culprit.

(Last edited by farrukh on 6 Jul 2015, 11:51)

Thanks. I know that the firewall isn't the issue as I don't have a 3rd party software one installed and my Windows ones are disabled.  I played with it for another hour and am going nuts.  Currently, I can get the transfer to at least start; but the router reboots almost immediately after the transfer or shortly thereafter and continues to reboot in the loop. 

I'm considering trying out the serial connection assuming my old serial -> usb converter will do the job.  Seems to be a lower level fix.  Was hoping to not have to perform surgery, but seems I'll have no choice.  Any more suggestions from anyone?  Thanks

Good morning!

I have the exact same problem, except my router is the Archer C7 AC1750. Another difference is that I meant to flash stock tplink firmware coming from openwrt. I did this using the mtd method, resulting in an endless bootloop.
So I resorted to the TFTP method, but I can't get it to transfer the firmware to the router.
Maybe you can help me, so I can hopefully contribute to the solution of the problem after I have setup everything the right way.
- How did you setup your nic in Windows? Did you leave the dns fields empty?
- How did you setup TFTP? Do you use the dhcp server? 
I hope you can help me with these settings, so I can start (or continue) troubleshooting and maybe we can solve this thing.

i was able to de-brick my Archer C7 v2 after my stupid attempt to revert back to stock directly from DDWRT's web gui. the steps may be similar if not the same for C5.

this is what i did (using windows 8 PC):
------------------------------------------------------------
- set my IP static to 192.168.0.66
- downloaded and installed Tftpd64 (http://tftpd32.jounin.net/tftpd32_download.html), and configured 'Current Directory' to a convenient directory, e.g. C:\folder
- named the firmware to flash to 'ArcherC7v2_tp_recovery.bin' and placed it in the directory*
- connected PC to ethernet port 1
- held down WPS/reset
- that's it - file started to transfer, and just wait as the router would reboot when done

*a tip for others: use Tftpd GUI's 'Log viewer' tab if you are not seeing any success - that's where i realized the recovery file name my router was looking for

(Last edited by dyeh on 24 Jul 2015, 18:56)

*a tip for others: use Tftpd GUI's 'Log viewer' tab if you are not seeing any success - that's where i realized the recovery file name my router was looking for
YOU BEST

The discussion might have continued from here.