Dynalink DL-WRX36 Askey RT5010W IPQ8072A technical discussion

Update 2:
My 2nd WRX36 SysUpgrade from Stable to Snapshot then to NSS build without issues. All can boot OK.

So it is only my 1st WRX36 failed to run Snapshot / NSS build - but Stable runs fine.

Can I copy partitions from 2nd WRX36 to 1st WRX36 to make then identical? Which partitions should be copied?

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Update 1:

I tried using 23.05.3, snapshot, and the NSS custom build.

Only 23.05.3 works by writing with ubiformat to /dev/mtd18 and /dev/mtd20

Both snapshot and NSS build will brick.

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My WRX36 softbricks again.

About 1 month ago my WRX36 is running snapshot fine for months.

Then after running AttendedSysUpgrade, it softbricked.

I just recover using Serial Console to 23.05.3 OK.

Then I download snapshot again, using Luci to flash the sysupgrade image - openwrt-qualcommax-ipq807x-dynalink_dl-wrx36-squashfs-sysupgrade.bin , then it softbricked again.

Serial Console is giving this error:

cpufreq: cpufreq_online: CPU0: Running at unlisted initial frequency: 800000 KHz, changing to: 1017600 KHz
[    1.208328] remoteproc remoteproc0: cd00000.q6v5_wcss is available
[    1.217642] UBI error: cannot open mtd rootfs, e�[    1.229127] Waiting for root device /dev/ubiblock0_1...

What is the correct way changing from stable to snapshot?