[Berlin-wireless] [OpenWrt-Devel] Cannot flash UBNT Loco M2

[Sven Roederer]

Hi,

eine auf diese Weise gebrickte NanoStation M5 (xm) konnte ich mit
folgendem Trick wieder gangbar machen:
- "U-Boot 1.1.4.2-s956 (Jun 10 2015 - 10:54:50)" war installiert aus
firmware 5.6 und unwillg zusammenzuarbeiten
- altes 5.5xm Image bei Ubiquiti runterladen
- im UBoot auf der nanoStation denn Rettungs-tftpserver mit der Option
"-f" starten (urescue -f) --> -f == "der Bootloader darf auch
überschrieben werden"
- das board bootet wieder mit AirOS 5.5
- normales Upgrade auf Kathleen (mit der Korrektur, die dann jedenfalls
im finalen kathleen 0.2.0 drin ist)

Bei der Gelegenheit kann man sich ja auch mal ein Backup des
Flashspeichers machen, nur für den Fall ...


Gruss Sven


On 11.03.2016 15:28, Matthias Schiffer wrote:
> Here's what's going on:
> 
> * OpenWrt had wrong partition sizes in its UBNT AirMax firmware for a long time
> * Old AirOS and the corresponding U-boot version had a bug that made U-boot
> ignore the partition sizes defined in the firmware image. This made OpenWrt
> work with the old U-boot despite its broken partition sizes
> * The new AirOS has been fixed in this regard (but contains a new bug).
> This also means that the broken OpenWrt images don't work anymore and can
> cause even more breakage
> * The new U-boot/AirOS did *not* change the flash layout. Both AirOS 5.5.x
> and 5.6.x use the same flash layout, the changed flash layout reported in
> the wiki is caused by broken OpenWrt images!
> * The OpenWrt trunk since r48829 and the CC branch since r48849 are fixed,
> meaning they define the correct partition sizes
> * The "Newly-erased block contained word ..." messages are a consequence of
> a missing patch in CC that has been backported as r48849 (the new U-boot
> doesn't remove flash protection, so the flash is just read-only from
> OpenWrt; TFTP recovery is the only way to upgrade in this state)
> * AFAIR "Error code 2 - Firmware Check Failed" is the consequence of a bug
> in the new U-boot: after flashing an image with broken (smaller) partition
> sizes, the recovery doesn't accept images with the original partition sizes
> anymore
> 
> Getting out of this state is not easy: you have a U-boot on your device
> that doesn't accept correct images, and an OpenWrt version that doesn't
> allow writing to the flash.

-------------- nächster Teil --------------
Ein Dateianhang mit Binärdaten wurde abgetrennt...
Dateiname   : signature.asc
Dateityp    : application/pgp-signature
Dateigröße  : 213 bytes
Beschreibung: OpenPGP digital signature
URL         : <https://lists.berlin.freifunk.net/pipermail/berlin/attachments/20160406/4869558e/attachment.sig>