HG556 Boot loop with 18.06 update

Hi, I have Hg556 working with OpenWrt and rooter 17.04.

Today I have tried to update to 18.06 with restart button method but it is rebooting continuosly.
I have also tried with the Luci upload option. Same. Boot loop

I have checked hardware version and download again 18.06 bin file. But boot loop always

Does anybody could help me?

Thanks

Try to hardflash your old version if possible
Get a serial connection on it

What instruction did you follow to "reset method" from 17.04 to 18.06?

I'm not that familiar with that router but you need to work out if this bootloop is POST or PRE hard update options for the device.

Which version exactly?

HG556a-A
HG556a-B
HG556a-C

18.06.0 or 18.06.1?

Which OpenWrt image exactly (please provide link)?

Thanks, I have try to update firmware with both methods: LUCI and with restart button, power on, keep 10 seconds and after that connect to 192.168.1.1 and select the new firmware to flash.
I think that is POST, as it keeps working a bit, after that reboot but then it goes in boot loop.

Hi, thanks. -A version.

http://downloads.openwrt.org/releases/18.06.1/targets/brcm63xx/smp/openwrt-18.06.1-brcm63xx-smp-HG556a-A-squashfs-cfe.bin

Try use http://downloads.openwrt.org/releases/18.06.1/targets/brcm63xx/generic/openwrt-18.06.1-brcm63xx-generic-HG556a-A-squashfs-cfe.bin - without smp

Thanks. My 17 version is smp. But I have tried generic version of 18.06 just in case.

Result: boot loop.

Hi, could you know what I could do to update to 18.06 ? Thanks.

Hi, how could help you to help me? Any log?

Hi
It happened to me. You need back to 17.01.4.

OEM easy installation
This section deals with how you install OpenWrt from the device freshly opened.
With this procedure you will flash the firmware using the bootloader web interface.
* Set a **static IP** on your computer, use 192.168.1.35 (or any compatible), and connect the ethernet cable to the router.
* Unplug the router's power cord
* Press the button labeled as *RESTART* , **don't** release it yet!
* Plug the power cord
* Wait 12 seconds or more
* Release the *RESTART* button
* Browse to `http://192.168.1.1`
* Select LEDE_17.01.4.bin firmware
* Press *Update Software* to start the firmware update process
* Wait for it to reboot

Then restore the cal_data partition with the instructions in page https://openwrt.org/toh/huawei/hg556a

If you want 18 version, you can. You must upgrade directly to snapshot 18 version from a functional 17.01.4 version, and you will not lose the calibration data, then you can install Luci package if you want.

Hi, how could I do it ? Are you saying about flashing from Luci interface (from 17.01.4 Luci interface) ?

Use "OEM easy installation" to reinstall 17.01.4, and then two situations:
1.- cal_data working. Upgrade to latest snapshot version from Luci interface.
2.- cal_data not working. Follow instructions to restore the cal_data partition, and then upgrade to latest snapshot version from Luci interface.
In any case, you should know that when you install a snapshot version Luci interface is lost, and you have to reinstall if you want it. Instructions in page https://openwrt.org/toh/huawei/hg556a