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Dev Issue 1

Problem Bugged U-boot

An experimental 8311 U-boot may trigger the U-boot shell rather than continue on with the boot process into OpenWrt when plugged into various host hardware, such as the Ubiquiti UDM-SE.

Take notice of the Hit any key to stop autoboot

ROM VER: 2.1.0
CFG 0d
B
DdrOk


U-Boot 2016.07-INTEL-v-3.1.210-8311 (Jul 08 2024 - 05:03:13 +0000), Build: prx126-sfp-qspi-nand-8311

interAptiv
cps cpu/ddr run in 400/400 Mhz
       Watchdog enabled
DRAM:  256 MiB
NAND:  device found, Manufacturer ID: 0xef, Chip ID: 0xaa
128 MiB
Bad block table found at page 65472, version 0x01
Bad block table found at page 65408, version 0x01
In:    serial
Out:   serial
Err:   serial
Reset cause: POR RESET
Net:   lan-0 config to 1G_XAUI_MODE, lan-1 config to 10G_KR_MODE, prx300-eth

run flash_flash to bring up the kernel

Hit any key to stop autoboot:  0
8311 #

Solution

The solution is to re-flash an OEM bootloader using a hardware host that does not trigger the event or that supports serial USB such as the SFP Media Buddy.

Note

The OEM bootloaders from Azores and Potron use Esc and Enter (or password) respectively to abort auto-boot and are highly unlikely to get triggered by a pulled-down Rate Select 0 pin (7).

SFP Media Buddy or other serial breakout hardware

If the boot process is interrupted, you can continue it along by issuing the run bootcmd command over serial.

MikroTik RouterOS

MikroTik RouterOS sets the Rate Select 0 pin high by default. If it was changed to low, try to revert back to default. Interfaces > Ethernet > SFP > Rate Select > high

/interface ethernet sfp-rate-select high

  1. Download the latest 8311 community release https://github.com/djGrrr/8311-was-110-firmware-builder/releases/latest.

    Note

    The 8311 community firmware includes the Azores bootloader with the preboot multicast upgrade feature as described in the guide:

    WAS-110 multicast upgrade and community firmware recovery

  2. Extract the bootloader from whole-image.img using Linux, macOS or WSL and verify it's integrity, i.e. uboot-azores.bin: OK.

    dd if=whole-image.img of=uboot-azores.bin conv=notrunc bs=1 count=216400
echo 'e757517fb8152c0e7b4db57f9cbef0576e2ff76dd45eea76596eddbaeb9e7b8d uboot-azores.bin' | sha256sum -c

  3. Transfer the extracted uboot-azores.bin onto the ONT.

    scp -O -oHostKeyAlgorithms=+ssh-rsa -oPubkeyAcceptedKeyTypes=+ssh-rsa uboot-azores.bin root@192.168.11.1:/tmp/

  4. Download nand-utils_2.1.1-1_mips_24kc.ipk from the 8311-was-110-firmware-builder repository1.

  5. Transfer and extract nand-utils_2.1.1-1_mips_24kc.ipk onto the ONT.

    tar -xOzf nand-utils_2.1.1-1_mips_24kc.ipk ./data.tar.gz | ssh -oHostKeyAlgorithms=+ssh-rsa -oPubkeyAcceptedKeyTypes=+ssh-rsa root@192.168.11.1 'tar -xzf - -C /tmp/'

  6. SSH into the ONT and verify the integrity of the transferred /tmp/uboot-azores.bin.

    ssh root@192.168.11.1
echo 'e757517fb8152c0e7b4db57f9cbef0576e2ff76dd45eea76596eddbaeb9e7b8d  /tmp/uboot-azores.bin' | sha256sum -c

  7. Erase partition and flash the /tmp/uboot-azores.bin bootloader into /dev/mtd0.

    Proceeding with the following commands can lead to a bricked device if things go awry

    /tmp/usr/sbin/flash_erase /dev/mtd0 0 0
/tmp/usr/sbin/nandwrite /dev/mtd0 -p /tmp/uboot-azores.bin

  8. Verify the integrity of the newly flashed bootloader e757517fb8152c0e7b4db57f9cbef0576e2ff76dd45eea76596eddbaeb9e7b8d.

    head -c 216400 /dev/mtd0 | sha256sum | cut -c 1-64 | grep -x 'e757517fb8152c0e7b4db57f9cbef0576e2ff76dd45eea76596eddbaeb9e7b8d' || echo 'failure' && echo 'verified'

  9. DO NOT continue to reboot unless the checksums match!!!

    reboot

  1. https://github.com/djGrrr/8311-was-110-firmware-builder ↩