Upgrading old RB to 6.48.5 makes cards boot-loop

Hi,
I have a float of 9xx (911* (lite and G, n and ac), 912*, 922*) and 433*
Upon upgrade to 6.48.5 (updating works fine), a lot of our old cards (that were on ≤ 6.47.9) cards reboot then boot-loop:

    1. all LEDs are on except traffic LED that is blinking


    1. after few seconds, the cards reboot


    1. repeat from 1

Tried to netinstall using push button but it goes back to 1. right after the blinking process (LEDs 1-5 ON for 5s, then blinking 5s, then ON 5s, then OFF 5s)
I’ve already lost a dozen cards that are (of course) out of warranty.

Please help..

Try to first netinstall 6.48.4 or 6.47.10 and update routerboot to this version before installing newer ROS.
For reference:
http://forum.mikrotik.com/t/v6-48-5-long-term-is-released/152469/1

I’d love to but cannot even put the cards in netinstall mode…

For boards with rs232 port you can access bootloader menu to do that (change boot device to bootp).
For rest, only button presses are available… some people reported bricked devices with no way out of this bootloop.

good, will try with 433* once i find a computer with serial port

9xx have rs232/jtag’ish testpins, isn’t it possible to use these to recover the cards? (and if so, with what settings? 9600/8/1?)
Thanks
IMG_20211201_150720.jpg

Sadly Mikrotik choose to disable UART pins completely so they are useless (there is no routerboot menu nor you can use them from ROS).
But they work perfectly fine if OpenWRT is flashed to the device… it’s completely software limitation… for no reason. Stupid!

As for JTAG, I haven’t had any luck with OpenOCD, but maybe there is some way to do it. But for boards with SPI memory it’s easier to just use test clip (or desolder it) and reprogram it directly as it’s just 8 pin chip.
But for big NAND chips it’s far more difficult, especially on rb9xx boards with BGA chips :frowning:

But whatever you do, please first contact support and make sure they understand how much they screwed up. Only way for things to improve in the future is if enough customers complain.
Talking here on forum is good to warn other users, but Mikrotik just doesn’t care. You can search for other topics with keywords like “brick” “bootloop”… not a single reply from anyone from Mikrotik.

good thinking, since i work for an integrator / official distributor, my company’s voice may accelerate things for everyone else too