summary observations - for newbies

This is a summary from a newbie. (YMMV - I could be wrong about a few of these observations, please modify or correct if wrong, or delete entirely!)

I am not on the fireCore team.. I'm simply an internet observer

fireCore beta requires a jailbroken AppleTV2 in order to install, the beta does not jailbreak an AppleTV2 for you

jailbreaking currently requires a "micro" usb cable, this is smaller than a "mini" usb cable, which is also smaller than a standard "B" USB connector, Apple stores sell a Griffin kit that has one and a keychain that has one - during jailbreaking the AppleTV is usb powered and should not be powered on through the main power cable - during TinyUmbrella SHSH blob backup the main power cable is required, but network connection through the AppleTV wired or AppleTV wireless connection is not needed, the SHSH blob is obtained through the jailbreaking computer

at this time because of the jailbreaking and the tethered "status" of the jailbreaking, it is an "advanced" skill level project to install and use the firecore beta - after jailbreaking it can be demanding to maintain the jailbroken status, casual users may want to wait for an untethered option described below

AppleTV About 4.0 = iOS 4.1 (8M89) (apple no longer signing, SHSH blobs no longer available, if you have SHSH blobs saved jailbreakable)

AppleTV About 4.1 = iOS 4.2.1 (8C150) (apple still signing, SHSH blobs are available, if you have SHSH blobs saved jailbreakable)

AppleTV About 4.1.1 = iOS 4.2.1 (8C154) (apple still signing, SHSH blobs are available, if you have SHSH blobs saved "not" jailbreakable at this time)

it seems Apple is retaining the ability to downgrade one version, but not beyond that, so you have until the next release of firmware to backup the SHSH blob for AppleTV About 4.1 = iOS 4.2.1 (8C150), when the next release of firmware after AppleTV About 4.1.1 = iOS 4.2.1 (8C154) is released - Apple will probably stop signing for AppleTV About 4.1 = iOS 4.2.1 (8C150) and those SHSH blobs will no longer be available.

TinyUmberella observes and captures the apple signing process and stores the result as an SHSH blob for future use. Then if you want to revert to a previous firmware version and have saved a copy of the old firmware, TinyUmbrella can stand in for Apple and intercept the request for signing and provide the previously saved SHSH blob making it possible to install the older firmware, even after Apple has stopped signing for the older firmware. Once Apple stops signing for older firmware if you do not have a backed up copy of the SHSH blob there is no way to restore an older copy of the firmware. TinyUmbrella calls AppleTV About 4.1 - AppleTV 4.2 (8C150) when it backs up the SSH blob, it appears to be a truncation of iOS 4.2.1 which is the firmware used in AppleTV About 4.1 (note: this is not all there is to reverting, the iTunes restore command normally does not offer a choice to choose an earlier firmware version, you must hiold down the Option key on a Mac while pressing the Restore button in iTunes to make it offer you a choice.. if you miss it you could end up missing the opportunity to restore an older version of firmware.. this is only one of several frustrating things that can happen.)

tethered "means" after its jailbroken it must never be allowed to sleep or reboot, otherwise it must be jailbroken again when it starts up, which requires it be connected to a jailbreaking computer - i.e. it remains tethered to its jailbreaking computer by micro usb cable

untethered "means" after its jailbroken it does not have to remain connected to its jailbreaking computer - i.e. it is untethered from the jailbreaking computer no micro usb cable need remain attached 

the jailbreaking process and tools are available from other sites, rumor has it that an "untethered" jailbreak will be available in or around xmas 12-25-2010, which will make the project much more worthwhile to the casual hacker looking to upgrade their device in a familiar fashion


Good guide.


Only thing I would vorrect is that the AppleTV is still jailbroken if it restars, it will just resuse to boot.


I say this because the whole process doesn't need repeating - it is simply one command line that copies a bootable kernel and iBSS files to the device and allows boot.

Thanks. Overall it's a pretty accurate summary.

The only thing I would add is that the 4.1.1 software is currently jailbreakable in the same way as the 4.1 version. A separate custom bundle for Pwnage Tool will be required, and it is still limited to a tethered jailbreak.

As this is for newbies it is importent to say that a tethered jailbreak is NOT to recommend for newbies

Sorry for all the spelling mistakes in my last post, I was in a rush. Tethered jailbreak is definitely not for newbies. Though if people are daring enough to go for it, we could probably write a batch for windows/Automator script for mac to do the tethered boot. Is there a way to force the AppleTv into dfu via USB? Though not much point as the untethered jailbreak is out soon.

Rumor is that unteathered jailbreak is released on Christmas Day.  Of course we will need nice scripts and instructions from someone.  Sooner or later.