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So, I've got a Nexus 7 and would like to start expirementing with images, etc (primary goal being installing Ubuntu in multiboot with Android, probably loading from a flash drive over an OTG cable).

My main concern (and hence the question) is:

I've heard, that rooting, unlocking the bootloader and flashing ROMs involve some dangeorus operations (like "fastboot erase boot loader") that can render the Nexus 7 unbootable if something goes wrong (i.e. the bootloader ends up in a messed state or erased).

Is there always a strong guarantee (not "99 out of 100, I'd say, if you're lucky") I can get the Nexus 7 to boot an OS with software-only means (i.e. USB cable, PC, and my hands pressing the hardware buttons on the tablet) if the above-described scenario takes place (i.e. the bootloader is ruined and the device refuses to boot)?

I've discovered that there exist different opinions on that matter, with some (obviously quite experienced) people telling one should not really worry about possible problems during image flashing and alike operations, and still others seem to struggle with what appears to be a Nexus 7 hard-bricked after an unsuccessful flash attempt.

For example:

  • This thread is a story of several Nexus 7 devices (hard) bricked with essentially a wrong sequence of fastboot (or alike) commands.

  • This fresh thread bears an example of "a knowldgeble guy" telling everything can be fixed.

Please note: this question is specifically about Nexus 7, and not about unbricking in general!

mlvljr
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  • This is more likely to get vote closed as its not a constructive question eliciting arguments from both sides of the camp, which is ... off-topic ... unless you edit the question in such a way you will get a definitive answer! And a question in relation to bricking has been answered before! this and this, and here – t0mm13b Jan 20 '13 at 23:44
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    BTW, the most reliable way of killing the device, this was true for Samsung using download mode, have the battery at < 5%, flash a ROM with Kies (known for bricking) or fastboot, either, two scenarios, battery goes flat during download of ROM flashing, or pull the cable during flashing, good luck with that! :) Then its JTAG time baby!! :) – t0mm13b Jan 21 '13 at 00:16
  • @t0mm13b - but still recoverable. – Ryan Conrad Jan 21 '13 at 00:42
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    @RyanConrad recoverable? You mean via JTAG, which is outside of the common average Joe user?, if yes, then yes its recoverable, but comes with a cost! – t0mm13b Jan 21 '13 at 00:46
  • @t0mm13b The reason the both sides are even mentioned is that there's only one answer (to a perfectly reasonable, and vital -- at least for the devices themselves, if not the owners) question, hence the question format, as there are quite different opinions on the topic. – mlvljr Jan 21 '13 at 09:55
  • "Not a real question?" Really, guys? :) – mlvljr Jan 21 '13 at 10:47
  • OP: If you notice how wildly varying each and everyone's opinions are within the comments/answer, its too broad and bordering on rhetorical question.. hence "Not a real question" – t0mm13b Jan 21 '13 at 16:58
  • @t0mm13b the fact that the answers vary does not make the question too broad, as it already quite precise. – mlvljr Jan 21 '13 at 17:02
  • Sorry OP, you've edited the question a few times, and the initial question was too broad then deleted bits out of it each time... it shows and telling thats the case. – t0mm13b Jan 21 '13 at 17:15
  • @t0mm13b I've edited the question for the wording to better match the site's rules as you guys see them, but the essence of the question and 95+% of the wording is the same; besides I deleted things only once -- per your request not to ask for a specific ("Yes"/"No") answer fromat, not multiple times :) – mlvljr Jan 21 '13 at 17:20

1 Answers1

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If you can get the device to boot to fastboot then you can "fix" a brick.

I have "soft bricked" my devices many times.

Samsung has "Download Mode", basically their version of fastboot. If you have an image that you can flash, you can recover. The same goes for the Nexus 7. If you have an image, which google provides because they are "developer" devices (as well as consumer).

The term "brick" is used very loosely and doesn't mean what it meant back in the WinMo days. When you bricked your WinMo phone it was as useful as a paperweight.

The only true bricks I have ever seen is when something fails in the hardware. Anything else that I have seen there is still a way to get to recovery, fastboot, download mode, etc. If you can get in to any of those you are golden.

Ryan Conrad
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    Heh! Still have that Dell Axim v51 with WinMob 6.5, but never powered it on, and was very dicey in flashing a newer WinMob ROM on it (Originally WinMob 6.0), far too dicey IIRC, it would fail if the big SDCard had a dodgy filesystem on it! :D – t0mm13b Jan 21 '13 at 00:13
  • Thanks, but what about specifically doing what the guys from one of my links did: "fastboot erase boot; ..."? Those who did it have perfect access to the stock images, but still are out of luck (due to the state of their devices -- no boot code, as I get it, and the lack of special tools (i.e. nvram) support for Nexus 7, unlike for example ASUS TF101). – mlvljr Jan 21 '13 at 10:02
  • In short, it is still perfectly possible (with a wrong sequence of actions and commands, but not physically damaging the device in any way) to make oneself not able to get to fastboot and thus hard-brick Nexus 7, right? – mlvljr Jan 21 '13 at 10:07
  • @mlvljr: unless it involves hardware failures like the driver instructing to put excessive voltages AND the hardware protection failed, I don't know of any way to permanently brick a device such that it cannot be recovered by someone with the right knowledge with the right tools. Many people gives up too early because they cannot find or didn't understand the fixing instruction or that they think the fix is not worth the effort. Many people draws a line that if it requires JTAG to fix, then it's hard bricked because it's not worth it to get the tools to fix it. – Lie Ryan Jan 21 '13 at 12:44
  • @LieRyan Ok, precisely: if one issues fastboot erase bootloader and then reboots, how can he make Nexus 7 boot whatever OS/image at all without JTAG (and alike means)? (note: there's no known way currently to use nvflash to flash a bootloader to Nexus 7 gone to APX mode, or smth like that (and thus essentially hard-bricked)). – mlvljr Jan 21 '13 at 13:18
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    @mlvljr If you wipe the bootloader from the storage and then wipe it from RAM with a reboot, you will need JTAG / a jig to reload the bootloader. – Matthew Read Jan 21 '13 at 20:21
  • @MatthewRead Ok, thanks, but google is almost silent on doing things this way with Nexus 7, so it looks like something one is not likely to succed with at home :) – mlvljr Jan 21 '13 at 20:32